ENGINE

SECTION

EC

ENGINE CONTROL SYSTEM

EC

CONTENTS
VQ37VHR
BASIC INSPECTION .................................... 9
DIAGNOSIS AND REPAIR WORKFLOW .......... 9
Work Flow ................................................................. 9
Diagnostic Work Sheet ............................................ 12

INSPECTION AND ADJUSTMENT ....................13

BASIC INSPECTION ................................................. 13
BASIC INSPECTION : Special Repair Requirement ........................................................................ 13
ADDITIONAL SERVICE WHEN REPLACING
CONTROL UNIT (ECM) ............................................. 16
ADDITIONAL SERVICE WHEN REPLACING
CONTROL UNIT (ECM) : Description ..................... 16
ADDITIONAL SERVICE WHEN REPLACING
CONTROL UNIT (ECM) : Special Repair Requirement ........................................................................ 16
ADDITIONAL SERVICE WHEN REPLACING
CONTROL UNIT (VVEL CONTROL MODULE) ........ 17
ADDITIONAL SERVICE WHEN REPLACING
CONTROL UNIT (VVEL CONTROL MODULE) :
Description .............................................................. 17
ADDITIONAL SERVICE WHEN REPLACING
CONTROL UNIT (VVEL CONTROL MODULE) :
Special Repair Requirement ................................... 17
IDLE SPEED .............................................................. 17
IDLE SPEED : Description ...................................... 17
IDLE SPEED : Special Repair Requirement ........... 17
IGNITION TIMING ...................................................... 17
IGNITION TIMING : Description .............................. 17
IGNITION TIMING : Special Repair Requirement.... 17
VIN REGISTRATION ................................................. 18
VIN REGISTRATION : Description ......................... 18
VIN REGISTRATION : Special Repair Requirement ........................................................................ 18

Revision: 2007 June

ACCELERATOR PEDAL RELEASED POSITION

LEARNING .................................................................18
ACCELERATOR PEDAL RELEASED POSITION
LEARNING : Description .........................................18
ACCELERATOR PEDAL RELEASED POSITION
LEARNING : Special Repair Requirement ..............18

THROTTLE VALVE CLOSED POSITION LEARNING .............................................................................18

THROTTLE VALVE CLOSED POSITION
LEARNING : Description .........................................18
THROTTLE VALVE CLOSED POSITION
LEARNING : Special Repair Requirement ..............18

IDLE AIR VOLUME LEARNING ................................19

IDLE AIR VOLUME LEARNING : Description .........19
IDLE AIR VOLUME LEARNING : Special Repair
Requirement ............................................................19

VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT ................................................................20

VVEL CONTROL SHAFT POSITION SENSOR
ADJUSTMENT : Description ...................................21
VVEL CONTROL SHAFT POSITION SENSOR
ADJUSTMENT : Special Repair Requirement ........21
MIXTURE RATIO SELF-LEARNING VALUE
CLEAR .......................................................................22
MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Description ................................................22
MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement .....................22

FUNCTION DIAGNOSIS .............................. 24

ENGINE CONTROL SYSTEM .......................... 24
System Diagram .....................................................24
System Description ..................................................25
Component Parts Location ......................................25
Component Description ...........................................32

MULTIPORT FUEL INJECTION SYSTEM ....... 34

EC-1

G37 Coupe

System Diagram .................................................... 34

System Description ................................................. 34
Component Parts Location ..................................... 37
Component Description .......................................... 43

ELECTRIC IGNITION SYSTEM ......................... 45

Component Function Check ................................. 132

Diagnosis Procedure ............................................. 133

POWER SUPPLY AND GROUND CIRCUIT .... 140

Diagnosis Procedure ............................................. 140

System Diagram .................................................... 45

System Description ................................................. 45
Component Parts Location ..................................... 46
Component Description .......................................... 52

U0113, U1003 CAN COMM CIRCUIT .............. 144

AIR CONDITIONING CUT CONTROL .............. 54

U1000, U1001 CAN COMM CIRCUIT .............. 146

System Diagram ..................................................... 54

System Description ................................................. 54
Component Parts Location ..................................... 55
Component Description .......................................... 61

AUTOMATIC SPEED CONTROL DEVICE

(ASCD) ............................................................... 62
System Diagram ..................................................... 62
System Description ................................................. 62
Component Parts Location ..................................... 64
Component Description ......................................... 70

Description ............................................................ 144

DTC Logic ............................................................. 144
Diagnosis Procedure ............................................. 144
Description ............................................................ 146
DTC Logic ............................................................. 146
Diagnosis Procedure ............................................. 146

U1010 CONTROL UNIT (CAN) ........................ 147

Description ............................................................ 147
DTC Logic ............................................................. 147
Diagnosis Procedure ............................................. 147

U1011 CONTROL UNIT (CAN) ........................ 148

CAN COMMUNICATION ................................... 71

Description ............................................................ 148

DTC Logic ............................................................. 148
Diagnosis Procedure ............................................. 148

System Description ................................................. 71

U1024 CAN COMM CIRCUIT ........................... 149

COOLING FAN CONTROL ............................... 72

Description ............................................................ 149

DTC Logic ............................................................. 149
Diagnosis Procedure ............................................. 149

System Diagram ..................................................... 72

System Description ................................................. 72
Component Parts Location ..................................... 73
Component Description .......................................... 79

EVAPORATIVE EMISSION SYSTEM ............... 80

System Diagram ..................................................... 80
System Description ................................................. 81
Component Parts Location ..................................... 83
Component Description ......................................... 89

INTAKE VALVE TIMING CONTROL ................. 91

System Diagram ..................................................... 91
System Description ................................................. 91
Component Parts Location ..................................... 92
Component Description .......................................... 98

VVEL SYSTEM .................................................. 99

System Diagram .................................................... 99
System Description ................................................. 99
Component Parts Location ....................................100
Component Description .........................................106

ON BOARD DIAGNOSTIC (OBD) SYSTEM ... 107

Diagnosis Description ............................................107
CONSULT-III Function ..........................................120
Diagnosis Tool Function ......................................129

COMPONENT DIAGNOSIS ....................... 132

P0011, P0021 IVT CONTROL .......................... 151

DTC Logic ............................................................. 151
Diagnosis Procedure ............................................. 152
Component Inspection .......................................... 153

P0031, P0032, P0051, P0052 A/F SENSOR 1

HEATER ........................................................... 155
Description ............................................................ 155
DTC Logic ............................................................. 155
Diagnosis Procedure ............................................. 156
Component Inspection .......................................... 157

P0037, P0038, P0057, P0058 HO2S2 HEATER ..................................................................... 158

Description ............................................................ 158
DTC Logic ............................................................. 158
Diagnosis Procedure ............................................. 159
Component Inspection .......................................... 160

P0075, P0081 IVT CONTROL SOLENOID

VALVE .............................................................. 162
Description ............................................................ 162
DTC Logic ............................................................. 162
Diagnosis Procedure ............................................. 162
Component Inspection .......................................... 163

P0101, P010B MAF SENSOR .......................... 165

TROUBLE DIAGNOSIS - SPECIFICATION
VALUE ............................................................. 132
Description .............................................................132

Revision: 2007 June

Description ............................................................ 165

DTC Logic ............................................................. 165
Component Function Check ................................. 167

EC-2

G37 Coupe

Diagnosis Procedure ............................................. 167

Component Inspection .......................................... 169

Diagnosis Procedure ............................................. 202

P0132, P0152 A/F SENSOR 1 ........................ 204

P0102, P0103, P010C, P010D MAF SENSOR.. 172

Description ............................................................ 172
DTC Logic ............................................................. 172
Diagnosis Procedure ............................................. 173
Component Inspection .......................................... 174

Description ............................................................. 204

DTC Logic .............................................................. 204
Diagnosis Procedure ............................................. 205
Description ............................................................. 207
DTC Logic .............................................................. 207
Diagnosis Procedure ............................................. 209

P0137, P0157 HO2S2 ..................................... 212

Description ............................................................. 212

DTC Logic .............................................................. 212
Component Function Check .................................. 213
Diagnosis Procedure ............................................. 214
Component Inspection ........................................... 215

P0138, P0158 HO2S2 ..................................... 218

Description ............................................................. 218

DTC Logic .............................................................. 218
Component Function Check .................................. 220
Diagnosis Procedure ............................................. 221
Component Inspection ........................................... 223

P0112, P0113 IAT SENSOR ............................ 181

Description ............................................................ 181
DTC Logic ............................................................. 181
Diagnosis Procedure ............................................. 182
Component Inspection .......................................... 182

P0117, P0118 ECT SENSOR ........................... 184

Description ............................................................ 184
DTC Logic ............................................................. 184
Diagnosis Procedure ............................................. 185
Component Inspection .......................................... 186

P0139, P0159 HO2S2 ..................................... 226

Description ............................................................. 226
DTC Logic .............................................................. 226
Component Function Check .................................. 227
Diagnosis Procedure ............................................. 228
Component Inspection ........................................... 229

P0122, P0123, P0227, P0228 TP SENSOR ..... 187

Description ............................................................ 187
DTC Logic ............................................................. 187
Diagnosis Procedure ............................................. 188
Component Inspection .......................................... 189
Special Repair Requirement ................................. 189

P0171, P0174 FUEL INJECTION SYSTEM

FUNCTION ...................................................... 232

P0125 ECT SENSOR ....................................... 190

DTC Logic .............................................................. 232

Diagnosis Procedure ............................................. 233

Description ............................................................ 190

DTC Logic ............................................................. 190
Diagnosis Procedure ............................................. 191
Component Inspection .......................................... 191

P0172, P0175 FUEL INJECTION SYSTEM

FUNCTION ...................................................... 236

P0127 IAT SENSOR ......................................... 193

DTC Logic .............................................................. 236

Diagnosis Procedure ............................................. 237

Description ............................................................ 193

DTC Logic ............................................................. 193
Diagnosis Procedure ............................................. 194
Component Inspection .......................................... 194

P0181 FTT SENSOR ....................................... 240

Description ............................................................. 240
DTC Logic .............................................................. 240
Diagnosis Procedure ............................................. 241
Component Inspection ........................................... 242

P0128 THERMOSTAT FUNCTION .................. 195

DTC Logic ............................................................. 195
Diagnosis Procedure ............................................. 195
Component Inspection .......................................... 196

P0182, P0183 FTT SENSOR .......................... 243

Description ............................................................. 243
DTC Logic .............................................................. 243
Diagnosis Procedure ............................................. 243
Component Inspection ........................................... 245

P0130, P0150 A/F SENSOR 1 ......................... 197

Description ............................................................ 197
DTC Logic ............................................................. 197
Component Function Check .................................. 199
Diagnosis Procedure ............................................. 199

P0196 EOT SENSOR ...................................... 246

P0131, P0151 A/F SENSOR 1 ......................... 201

Description ............................................................ 201
DTC Logic ............................................................. 201

Revision: 2007 June

EC

P0133, P0153 A/F SENSOR 1 ........................ 207

P010A MANIFOLD ABSOLUTE PRESSURE

SENSOR ........................................................... 177
Description ............................................................ 177
DTC Logic ............................................................. 177
Diagnosis Procedure ............................................. 177
Component Inspection .......................................... 178

EC-3

Description ............................................................. 246

DTC Logic .............................................................. 246
Diagnosis Procedure ............................................. 247
Component Inspection ........................................... 248

G37 Coupe

P0197, P0198 EOT SENSOR .......................... 249

Description .............................................................249
DTC Logic ..............................................................249
Diagnosis Procedure .............................................250
Component Inspection ...........................................250

P0222, P0223, P2132, P2133 TP SENSOR .... 252

Description .............................................................252
DTC Logic ..............................................................252
Diagnosis Procedure .............................................253
Component Inspection ...........................................254
Special Repair Requirement ..................................254

P0300, P0301, P0302, P0303, P0304, P0305,

P0306 MISFIRE ............................................... 255
DTC Logic ..............................................................255
Diagnosis Procedure .............................................256

P0327, P0328, P0332, P0333 KS .................... 261

Description .............................................................261
DTC Logic ..............................................................261
Diagnosis Procedure .............................................261
Component Inspection ...........................................262

P0335 CKP SENSOR (POS) ........................... 264

Description .............................................................264
DTC Logic ..............................................................264
Diagnosis Procedure .............................................265
Component Inspection ...........................................267

P0340, P0345 CMP SENSOR (PHASE) .......... 268

Description .............................................................268
DTC Logic ..............................................................268
Diagnosis Procedure .............................................269
Component Inspection ...........................................271

P0420, P0430 THREE WAY CATALYST

FUNCTION ....................................................... 272
DTC Logic ..............................................................272
Component Function Check ..................................273
Diagnosis Procedure .............................................274

P0441 EVAP CONTROL SYSTEM .................. 277

DTC Logic ..............................................................277
Component Function Check ..................................278
Diagnosis Procedure .............................................279

P0442 EVAP CONTROL SYSTEM .................. 282

DTC Logic ..............................................................282
Diagnosis Procedure .............................................283
Component Inspection ...........................................287

P0443 EVAP CANISTER PURGE VOLUME

CONTROL SOLENOID VALVE ....................... 288
Description .............................................................288
DTC Logic ..............................................................288
Diagnosis Procedure .............................................289
Component Inspection ...........................................291

P0444, P0445 EVAP CANISTER PURGE

VOLUME CONTROL SOLENOID VALVE ...... 293
Revision: 2007 June

Description ............................................................ 293

DTC Logic ............................................................. 293
Diagnosis Procedure ............................................. 293
Component Inspection .......................................... 295

P0447 EVAP CANISTER VENT CONTROL

VALVE .............................................................. 296
Description ............................................................ 296
DTC Logic ............................................................. 296
Diagnosis Procedure ............................................. 296
Component Inspection .......................................... 298

P0448 EVAP CANISTER VENT CONTROL

VALVE .............................................................. 300
Description ............................................................ 300
DTC Logic ............................................................. 300
Diagnosis Procedure ............................................. 301
Component Inspection .......................................... 302

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR ................................................ 304

Description ............................................................ 304
DTC Logic ............................................................. 304
Diagnosis Procedure ............................................. 304
Component Inspection .......................................... 306

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR ................................................ 307

Description ............................................................ 307
DTC Logic ............................................................. 307
Diagnosis Procedure ............................................. 308
Component Inspection .......................................... 310

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR ................................................ 312

Description ............................................................ 312
DTC Logic ............................................................. 312
Diagnosis Procedure ............................................. 313
Component Inspection .......................................... 316

P0455 EVAP CONTROL SYSTEM .................. 318

DTC Logic ............................................................. 318
Diagnosis Procedure ............................................. 320
Component Inspection .......................................... 322

P0456 EVAP CONTROL SYSTEM .................. 324

DTC Logic ............................................................. 324
Component Function Check ................................. 326
Diagnosis Procedure ............................................. 326
Component Inspection .......................................... 330

P0460 FUEL LEVEL SENSOR ......................... 331

Description ............................................................ 331
DTC Logic ............................................................. 331
Diagnosis Procedure ............................................. 331

P0461 FUEL LEVEL SENSOR ......................... 333

Description ............................................................ 333
DTC Logic ............................................................. 333
Component Function Check ................................. 333
Diagnosis Procedure ............................................. 334

EC-4

G37 Coupe

P0462, P0463 FUEL LEVEL SENSOR ............ 335

Diagnosis Procedure ............................................. 365

Component Inspection (VVEL ACTUATOR MOTOR) ...................................................................... 367
Component Inspection (VVEL ACTUATOR SUB
ASSEMBLY) .......................................................... 368
Special Repair Requirement .................................. 368

Description ............................................................ 335

DTC Logic ............................................................. 335
Diagnosis Procedure ............................................. 335

P0500 VSS ....................................................... 337

Description ............................................................ 337
DTC Logic ............................................................. 337
Component Function Check .................................. 338
Diagnosis Procedure ............................................. 338

P0506 ISC SYSTEM ......................................... 339

DTC Logic .............................................................. 369

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR ............................................. 370

Description ............................................................. 370
DTC Logic .............................................................. 370
Diagnosis Procedure ............................................. 370
Special Repair Requirement .................................. 373

P0507 ISC SYSTEM ......................................... 341

Description ............................................................. 374

DTC Logic .............................................................. 374
Diagnosis Procedure ............................................. 374
Component Inspection (VVEL ACTUATOR MOTOR) ...................................................................... 376
Component Inspection (VVEL ACTUATOR SUB
ASSEMBLY) .......................................................... 377
Special Repair Requirement .................................. 377

DTC Logic ............................................................. 343

Diagnosis Procedure ............................................. 344
Component Inspection .......................................... 345

P0550 PSP SENSOR ....................................... 346

P0555 BRAKE BOOSTER PRESSURE SENSOR .................................................................. 349

Description ............................................................ 349
DTC Logic ............................................................. 349
Diagnosis Procedure ............................................. 349
Component Inspection .......................................... 352

Description ............................................................. 378

DTC Logic .............................................................. 378
Diagnosis Procedure ............................................. 378
Component Inspection ........................................... 380

P1148, P1168 CLOSED LOOP CONTROL .... 381

DTC Logic .............................................................. 381

P1211 TCS CONTROL UNIT .......................... 382

Description ............................................................. 382
DTC Logic .............................................................. 382
Diagnosis Procedure ............................................. 382

P1212 TCS COMMUNICATION LINE ............. 383

Description ............................................................. 383
DTC Logic .............................................................. 383
Diagnosis Procedure ............................................. 383

P0605 ECM ....................................................... 356

Description ............................................................ 356
DTC Logic ............................................................. 356
Diagnosis Procedure ............................................. 357

P1091 VVEL ACTUATOR MOTOR RELAY ... 378

P0603 ECM POWER SUPPLY ......................... 354

Description ............................................................ 354
DTC Logic ............................................................. 354
Diagnosis Procedure ............................................. 354

P1090, P1093 VVEL ACTUATOR MOTOR .... 374

P0524 ENGINE OIL PRESSURE ..................... 343

Description ............................................................ 346

DTC Logic ............................................................. 346
Diagnosis Procedure ............................................. 346
Component Inspection .......................................... 347

EC

P1087, P1088 VVEL SYSTEM ........................ 369

Description ............................................................ 339

DTC Logic ............................................................. 339
Diagnosis Procedure ............................................. 339
Description ............................................................ 341
DTC Logic ............................................................. 341
Diagnosis Procedure ............................................. 341

P1217 ENGINE OVER TEMPERATURE ........ 384

P0643 SENSOR POWER SUPPLY ................. 358

DTC Logic .............................................................. 384

Component Function Check .................................. 384
Diagnosis Procedure ............................................. 385

DTC Logic ............................................................. 358

Diagnosis Procedure ............................................. 358

P1225, P1234 TP SENSOR ............................ 388

Description ............................................................. 388
DTC Logic .............................................................. 388
Diagnosis Procedure ............................................. 388
Special Repair Requirement .................................. 389

P0850 PNP SWITCH ........................................ 361

Description ............................................................ 361
DTC Logic ............................................................. 361
Component Function Check .................................. 362
Diagnosis Procedure ............................................. 362

P1226, P1235 TP SENSOR ............................ 390

P100A, P100B VVEL SYSTEM ........................ 365

DTC Logic ............................................................. 365

Revision: 2007 June

EC-5

Description ............................................................. 390

DTC Logic .............................................................. 390
Diagnosis Procedure ............................................. 390

G37 Coupe

Special Repair Requirement ..................................391

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION ............................................ 392

Description .............................................................392
DTC Logic ..............................................................392
Diagnosis Procedure .............................................392
Component Inspection ...........................................395
Special Repair Requirement ..................................395

P1236, P2118 THROTTLE CONTROL MOTOR .................................................................. 396

Description .............................................................396
DTC Logic ..............................................................396
Diagnosis Procedure .............................................396
Component Inspection ...........................................397
Special Repair Requirement ..................................398

P1238, P2119 ELECTRIC THROTTLE CONTROL ACTUATOR .......................................... 399

Description .............................................................399
DTC Logic ..............................................................399
Diagnosis Procedure .............................................400
Special Repair Requirement ..................................400

P1239, P2135 TP SENSOR ............................. 401

Description .............................................................401
DTC Logic ..............................................................401
Diagnosis Procedure .............................................401
Component Inspection ...........................................403
Special Repair Requirement ..................................403

P1290, P2100, P2103 THROTTLE CONTROL

MOTOR RELAY ............................................... 404
Description .............................................................404
DTC Logic ..............................................................404
Diagnosis Procedure .............................................404

P1421 COLD START CONTROL .................... 406

Description .............................................................406
DTC Logic ..............................................................406
Diagnosis Procedure .............................................406

P1550 BATTERY CURRENT SENSOR .......... 408

Description .............................................................408
DTC Logic ..............................................................408
Diagnosis Procedure .............................................408
Component Inspection ...........................................410

P1554 BATTERY CURRENT SENSOR ........... 417

Description ............................................................ 417
DTC Logic ............................................................. 417
Component Function Check ................................. 417
Diagnosis Procedure ............................................. 418
Component Inspection .......................................... 419

P1564 ASCD STEERING SWITCH .................. 421

Description ............................................................ 421
DTC Logic ............................................................. 421
Diagnosis Procedure ............................................. 421
Component Inspection .......................................... 423

P1564 ICC STEERING SWITCH ...................... 424

Description ............................................................ 424
DTC Logic ............................................................. 424
Diagnosis Procedure ............................................. 424
Component Inspection .......................................... 426

P1568 ICC FUNCTION ..................................... 427

DTC Logic ............................................................. 427
Diagnosis Procedure ............................................. 427

P1572 ASCD BRAKE SWITCH ........................ 428

Description ............................................................ 428
DTC Logic ............................................................. 428
Diagnosis Procedure ............................................. 429
Component Inspection (ASCD Brake Switch) ....... 433
Component Inspection (ASCD Clutch Switch) ...... 434
Component Inspection (Stop Lamp Switch) .......... 434

P1572 ICC BRAKE SWITCH ............................ 435

Description ............................................................ 435
DTC Logic ............................................................. 435
Diagnosis Procedure ............................................. 436
Component Inspection (ICC Brake Switch) .......... 441
Component Inspection (ICC Clutch Switch) .......... 441
Component Inspection (Stop Lamp Switch) .......... 442
Component Inspection (ICC Brake Hold Relay) ... 442

P1574 ASCD VEHICLE SPEED SENSOR ....... 443

Description ............................................................ 443
DTC Logic ............................................................. 443
Diagnosis Procedure ............................................. 443

P1574 ICC VEHICLE SPEED SENSOR ........... 445

Description ............................................................ 445
DTC Logic ............................................................. 445
Diagnosis Procedure ............................................. 445

P1551, P1552 BATTERY CURRENT SENSOR .................................................................. 411

P1606 VVEL CONTROL MODULE .................. 447

Description .............................................................411
DTC Logic ..............................................................411
Diagnosis Procedure .............................................411
Component Inspection ...........................................413

P1607 VVEL CONTROL MODULE .................. 449

P1553 BATTERY CURRENT SENSOR .......... 414

Description .............................................................414
DTC Logic ..............................................................414
Diagnosis Procedure .............................................414
Component Inspection ...........................................416

Revision: 2007 June

Description ............................................................ 447

DTC Logic ............................................................. 447
Diagnosis Procedure ............................................. 447
Description ............................................................ 449
DTC Logic ............................................................. 449
Diagnosis Procedure ............................................. 449

P1608 VVEL SENSOR POWER SUPPLY ....... 451

EC-6

G37 Coupe

DTC Logic ............................................................. 451

Diagnosis Procedure ............................................. 451
Special Repair Requirement ................................. 452

P1715 INPUT SPEED SENSOR (TURBINE

REVOLUTION SENSOR) ................................. 454

ELECTRICAL LOAD SIGNAL ........................ 485

Description ............................................................. 485
Component Function Check .................................. 485
Diagnosis Procedure ............................................. 485

FUEL INJECTOR ............................................ 487 EC

Description ............................................................ 454

DTC Logic ............................................................. 454
Diagnosis Procedure ............................................. 454

Description ............................................................. 487

Component Function Check .................................. 487
Diagnosis Procedure ............................................. 487
Component Inspection ........................................... 489

P1805 BRAKE SWITCH ................................... 455

Description ............................................................ 455
DTC Logic ............................................................. 455
Diagnosis Procedure ............................................. 455
Component Inspection (Stop Lamp Switch) .......... 456

FUEL PUMP .................................................... 490

Description ............................................................. 490
Component Function Check .................................. 490
Diagnosis Procedure ............................................. 490
Component Inspection ........................................... 492

P2122, P2123 APP SENSOR ........................... 458

Description ............................................................ 458
DTC Logic ............................................................. 458
Diagnosis Procedure ............................................. 458
Component Inspection .......................................... 460
Special Repair Requirement ................................. 460

Description ............................................................. 493

Component Function Check .................................. 493
Diagnosis Procedure ............................................. 493
Component Inspection (ICC Brake Switch) ........... 496
Component Inspection (ICC Clutch Switch) .......... 496

P2A00, P2A03 A/F SENSOR 1 ........................ 471

Description ............................................................ 471
DTC Logic ............................................................. 471
Diagnosis Procedure ............................................. 472

COOLING FAN ................................................. 481

Description ............................................................ 481
Component Function Check .................................. 481
Diagnosis Procedure ............................................. 481
Component Inspection (Cooling Fan Motor) ......... 483
Component Inspection (Cooling Fan Relay) ......... 484

Revision: 2007 June

MALFUNCTION INDICATOR LAMP .............. 503

Description ............................................................. 503

Component Function Check .................................. 503
Diagnosis Procedure ............................................. 503

ON BOARD REFUELING VAPOR RECOVERY (ORVR) .................................................... 504

Description ............................................................. 504
Component Function Check .................................. 504
Diagnosis Procedure ............................................. 504
Component Inspection ........................................... 507

POSITIVE CRANKCASE VENTILATION ....... 509

Description ............................................................. 509
Component Inspection ........................................... 509

REFRIGERANT PRESSURE SENSOR .......... 511

ASCD INDICATOR ........................................... 480

Description ............................................................ 480
Component Function Check .................................. 480
Diagnosis Procedure ............................................. 480

Description ............................................................. 498

Component Function Check .................................. 498
Diagnosis Procedure ............................................. 498
Component Inspection (Ignition Coil with Power
Transistor) ............................................................. 501
Component Inspection (Condenser) ...................... 502

ASCD BRAKE SWITCH ................................... 475

Description ............................................................ 475
Component Function Check .................................. 475
Diagnosis Procedure ............................................. 475
Component Inspection (ASCD Brake Switch) ....... 478
Component Inspection (ASCD Clutch Switch) ...... 478

IGNITION SIGNAL .......................................... 498

P2138 APP SENSOR ....................................... 466

Description ............................................................ 466
DTC Logic ............................................................. 466
Diagnosis Procedure ............................................. 467
Component Inspection .......................................... 469
Special Repair Requirement ................................. 470

ICC BRAKE SWITCH ...................................... 493

P2127, P2128 APP SENSOR ........................... 462

Description ............................................................ 462
DTC Logic ............................................................. 462
Diagnosis Procedure ............................................. 463
Component Inspection .......................................... 465
Special Repair Requirement ................................. 465

Description ............................................................. 511

Component Function Check .................................. 511
Diagnosis Procedure ............................................. 511

ECU DIAGNOSIS ....................................... 513

ECM ................................................................. 513

EC-7

Reference Value .................................................... 513

Wiring Diagram - ENGINE CONTROL SYSTEM -.. 529
Fail Safe ................................................................ 548
DTC Inspection Priority Chart ............................. 550
DTC Index ............................................................. 552

G37 Coupe

How to Set SRT Code ........................................557

Test Value and Test Limit ...................................560

VVEL CONTROL MODULE ............................. 565

Reference Value ....................................................565
Wiring Diagram - ENGINE CONTROL SYSTEM -..569

SYMPTOM DIAGNOSIS ............................ 589

PREPARATION ................................................ 599

Special Service Tools ........................................... 599
Commercial Service Tools .................................... 599

ON-VEHICLE MAINTENANCE ................. 601

FUEL PRESSURE ............................................ 601
Inspection .............................................................. 601

ENGINE CONTROL SYSTEM SYMPTOMS ... 589

EVAP LEAK CHECK ........................................ 602

Symptom Table .....................................................589

Inspection .............................................................. 602

NORMAL OPERATING CONDITION .............. 593

ON-VEHICLE REPAIR .............................. 604

Description .............................................................593

PRECAUTION ............................................ 594

PRECAUTIONS ............................................... 594
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TENSIONER" ................................................................594
Precaution for Procedure without Cowl Top Cover..594
Precautions For Xenon Headlamp Service ...........594
On Board Diagnostic (OBD) System of Engine
and A/T ..................................................................595
General Precautions ..............................................595

PREPARATION .......................................... 599

Revision: 2007 June

EVAP CANISTER ............................................. 604

Exploded View ...................................................... 604
Removal and Installation ....................................... 604
Inspection .............................................................. 605

SERVICE DATA AND SPECIFICATIONS

(SDS) ......................................................... 606
SERVICE DATA AND SPECIFICATIONS
(SDS) ................................................................ 606
Idle Speed ............................................................. 606
Ignition Timing ....................................................... 606
Calculated Load Value .......................................... 606
Mass Air Flow Sensor ........................................... 606

EC-8

G37 Coupe

DIAGNOSIS AND REPAIR WORKFLOW

[VQ37VHR]

< BASIC INSPECTION >

BASIC INSPECTION

DIAGNOSIS AND REPAIR WORKFLOW

Work Flow

INFOID:0000000001733906

EC

OVERALL SEQUENCE
C

JMBIA0078GB

DETAILED FLOW
Revision: 2007 June

EC-9

G37 Coupe

DIAGNOSIS AND REPAIR WORKFLOW

[VQ37VHR]

< BASIC INSPECTION >

1.GET INFORMATION FOR SYMPTOM

Get the detailed information from the customer about the symptom (the condition and the environment when
the incident/malfunction occurred) using the Diagnostic Work Sheet. (Refer to EC-12, "Diagnostic Work
Sheet".)
>> GO TO 2.

2.CHECK DTC
1.
2.
-

Check DTC.
Perform the following procedure if DTC is displayed.
Record DTC and freeze frame data. (Print them out with CONSULT-III or GST.)
Erase DTC. (Refer to EC-107, "Diagnosis Description".)
Study the relationship between the cause detected by DTC and the symptom described by the customer.
(Symptom Matrix Chart is useful. Refer to EC-589, "Symptom Table".)
3. Check related service bulletins for information.
Is any symptom described and is any DTC detected?
Symptom is described, DTC is detected>>GO TO 3.
Symptom is described, DTC is not detected>>GO TO 4.
Symptom is not described, DTC is detected>>GO TO 5.

3.CONFIRM THE SYMPTOM

Try to confirm the symptom described by the customer (except MIL ON).
Also study the normal operation and fail safe related to the symptom. Refer to EC-593, "Description" and EC548, "Fail Safe".
Diagnosis Work Sheet is useful to verify the incident.
Verify relation between the symptom and the condition when the symptom is detected.
>> GO TO 5.

4.CONFIRM THE SYMPTOM

Try to confirm the symptom described by the customer.
Also study the normal operation and fail safe related to the symptom. Refer to EC-593, "Description" and EC548, "Fail Safe".
Diagnosis Work Sheet is useful to verify the incident.
Verify relation between the symptom and the condition when the symptom is detected.
>> GO TO 6.

5.PERFORM DTC CONFIRMATION PROCEDURE

Perform DTC CONFIRMATION PROCEDURE for the displayed DTC, and then make sure that DTC is
detected again.
If two or more DTCs are detected, refer to EC-550, "DTC Inspection Priority Chart" and determine trouble
diagnosis order.
NOTE:
Freeze frame data is useful if the DTC is not detected.
Perform Component Function Check if DTC CONFIRMATION PROCEDURE is not included on Service
Manual. This simplified check procedure is an effective alternative though DTC cannot be detected during
this check.
If the result of Component Function Check is NG, it is the same as the detection of DTC by DTC CONFIRMATION PROCEDURE.
Is DTC detected?
YES >> GO TO 10.
NO
>> Check according to GI-38, "Intermittent Incident".

6.PERFORM BASIC INSPECTION

Perform EC-13, "BASIC INSPECTION : Special Repair Requirement".
Do you have CONSULT-III?
Revision: 2007 June

EC-10

G37 Coupe

DIAGNOSIS AND REPAIR WORKFLOW

[VQ37VHR]

< BASIC INSPECTION >

YES >> GO TO 7.
NO
>> GO TO 9.

7.PERFORM SPEC IN DATA MONITOR MODE

With CONSULT-III
EC
Make sure that MAS A/F SE-B1, MAS A/F SE-B2, B/FUEL SCHDL, and A/F ALPHA-B1, A/F ALPHAB2 are within the SP value using CONSULT-III SPEC in DATA MONITOR mode. Refer to EC-132, "Component Function Check".
C
Is the measurement value within the SP value?
YES >> GO TO 9.
NO
>> GO TO 8.
D
DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE

8.

Detect malfunctioning part according to EC-133, "Diagnosis Procedure".

Is malfunctioning part detected?
YES >> GO TO 11.
NO
>> GO TO 9.

9.DETECT MALFUNCTIONING SYSTEM BY SYMPTOM TABLE

Detect malfunctioning system according to EC-589, "Symptom Table" based on the confirmed symptom in
step 4, and determine the trouble diagnosis order based on possible causes and symptom.

>> GO TO 10.

10.DETECT MALFUNCTIONING PART BY DIAGNOSIS PROCEDURE

Inspect according to Diagnosis Procedure of the system.

NOTE:
The Diagnosis Procedure in EC section described based on open circuit inspection. A short circuit inspection
is also required for the circuit check in the Diagnosis Procedure. For details, refer to GI-41, "Circuit Inspection".
Is malfunctioning part detected?
YES >> GO TO 11.
NO
>> Monitor input data from related sensors or check voltage of related ECM terminals using CONSULT-III. Refer to EC-513, "Reference Value".

11.REPAIR OR REPLACE THE MALFUNCTIONING PART

1.
2.
3.

Repair or replace the malfunctioning part.

Reconnect parts or connectors disconnected during Diagnosis Procedure again after repair and replacement.
Check DTC. If DTC is displayed, erase it. Refer to EC-107, "Diagnosis Description".

>> GO TO 12.

12.FINAL CHECK
When DTC was detected in step 2, perform DTC CONFIRMATION PROCEDURE or Component Function
Check again, and then make sure that the malfunction have been repaired securely.
When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and make sure
that the symptom is not detected.
Is DTC detected and does symptom remain?
YES-1 >> DTC is detected: GO TO 10.
YES-2 >> Symptom remains: GO TO 6.
NO
>> Before returning the vehicle to the customer, make sure to erase unnecessary DTC in ECM and
TCM (Transmission Control Module). (Refer to EC-107, "Diagnosis Description".) If the completion of SRT is needed, drive vehicle under the specific driving pattern. Refer to EC-557,
"How to Set SRT Code".

Revision: 2007 June

EC-11

G37 Coupe

DIAGNOSIS AND REPAIR WORKFLOW

[VQ37VHR]

< BASIC INSPECTION >

Diagnostic Work Sheet

INFOID:0000000001733907

DESCRIPTION
There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make troubleshooting faster and more accurate.
In general, each customer feels differently about a incident. It is
important to fully understand the symptoms or conditions for a customer complaint.
Utilize a diagnostic worksheet like the one on the next page in order
to organize all the information for troubleshooting.
Some conditions may cause the MIL to come on steady or blink and
DTC to be detected. Examples:
Vehicle ran out of fuel, which caused the engine to misfire.
Fuel filler cap was left off or incorrectly screwed on, allowing fuel to
evaporate into the atmosphere.

SEF907L

WORKSHEET SAMPLE

MTBL0017

Revision: 2007 June

EC-12

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

INSPECTION AND ADJUSTMENT

BASIC INSPECTION
BASIC INSPECTION : Special Repair Requirement

INFOID:0000000001733908

EC

1.INSPECTION START
1.
2.
3.
4.

Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.
Open engine hood and check the following:
Harness connectors for improper connections
Wiring harness for improper connections, pinches and cut
Vacuum hoses for splits, kinks and improper connections
Hoses and ducts for leaks
Air cleaner clogging
Gasket
Confirm that electrical or mechanical loads are not applied.
Headlamp switch is OFF.
Air conditioner switch is OFF.
Rear window defogger switch is OFF.
SEF983U
Steering wheel is in the straight-ahead position, etc.
Start engine and warm it up until engine coolant temperature
indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.

SEF976U

Run engine at about 2,000 rpm for about 2 minutes under no

load.
6. Make sure that no DTC is displayed with CONSULT-III or GST.
Is any DTC detected?
YES >> GO TO 2.
NO
>> GO TO 3.

5.

M
SEF977U

2.REPAIR OR REPLACE

Repair or replace components as necessary according to corresponding Diagnosis Procedure.

O

>> GO TO 3

3.CHECK TARGET IDLE SPEED

1.

Run engine at about 2,000 rpm for about 2 minutes under no load.

Revision: 2007 June

EC-13

G37 Coupe

INSPECTION AND ADJUSTMENT

< BASIC INSPECTION >
2. Rev engine (2,000 to 3,000 rpm) two or three times under no
load, then run engine at idle speed for about 1 minute.
3. Check idle speed.
For procedure, refer to EC-17, "IDLE SPEED : Special Repair
Requirement".
For specification, refer to EC-606, "Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 4.

[VQ37VHR]

PBIA8513J

4.PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

1.
2.

Stop engine.
Perform EC-18, "ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement".
>> GO TO 5.

5.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
>> GO TO 6.

6.PERFORM IDLE AIR VOLUME LEARNING

Perform EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 7.
NO
>> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.

7.CHECK TARGET IDLE SPEED AGAIN

1.
2.

Start engine and warm it up to normal operating temperature.

Check idle speed.
For procedure, refer to EC-17, "IDLE SPEED : Special Repair Requirement".
For specification, refer to EC-606, "Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the Following.
Check camshaft position sensor (PHASE) and circuit. Refer to EC-271, "Component Inspection".
Check crankshaft position sensor (POS) and circuit. Refer to EC-267, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Repair or replace. Then GO TO 4.

9.CHECK ECM FUNCTION

1.
2.

Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
SEC-8, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement".
>> GO TO 4.

10.CHECK IGNITION TIMING

1.

Run engine at idle.

Revision: 2007 June

EC-14

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

2. Check ignition timing with a timing light.

A
A

:Timing indicator

For procedure, refer to EC-17, "IGNITION TIMING : Special

Repair Requirement".
For specification, refer to EC-606, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO
>> GO TO 11.

EC

C
JMBIA0054ZZ

11.PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

1.
2.

Stop engine.
Perform EC-18, "ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement".
>> GO TO 12.

12.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".

>> GO TO 13.

13.PERFORM IDLE AIR VOLUME LEARNING

Perform EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".

Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 14.
NO
>> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.

14.CHECK TARGET IDLE SPEED AGAIN

1.
2.

Start engine and warm it up to normal operating temperature.

Check idle speed.
For procedure, refer to EC-17, "IDLE SPEED : Special Repair Requirement".
For specification, refer to EC-606, "Idle Speed".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> GO TO 17.

15.CHECK IGNITION TIMING AGAIN

1.
2.

Run engine at idle.

Check ignition timing with a timing light.
A

:Timing indicator

For procedure, refer to EC-17, "IGNITION TIMING : Special

Repair Requirement".
For specification, refer to EC-606, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO
>> GO TO 16.

P
JMBIA0054ZZ

16.CHECK TIMING CHAIN INSTALLATION

Check timing chain installation. Refer to EM-49, "Removal and Installation".
Is the inspection result normal?
YES >> GO TO 17.
NO
>> Repair the timing chain installation. Then GO TO 4.
Revision: 2007 June

EC-15

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

17.DETECT MALFUNCTIONING PART

Check the following.
Check camshaft position sensor (PHASE) and circuit. Refer to EC-271, "Component Inspection".
Check crankshaft position sensor (POS) and circuit. Refer to EC-267, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 18.
NO
>> Repair or replace. Then GO TO 4.

18.CHECK ECM FUNCTION

1.
2.

Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
SEC-8, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement".
>> GO TO 4.

19.INSPECTION END
If ECM is replaced during this BASIC INSPECTION procedure, go to EC-16, "ADDITIONAL SERVICE WHEN
REPLACING CONTROL UNIT (ECM) : Special Repair Requirement".
>> INSPECTION END

ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM)

ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Description
INFOID:0000000001733909

When replacing ECM, this procedure must be performed.

ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair

Requirement

INFOID:0000000001733910

1.PERFORM INITIALIZATION OF NATS SYSTEM AND REGISTRATION OF ALL NATS IGNITION KEY IDS
Refer to SEC-8, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement".
>> GO TO 2.

2.PERFORM VIN REGISTRATION

Refer to EC-18, "VIN REGISTRATION : Special Repair Requirement".
>> GO TO 3.

3.PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

Refer to EC-18, "ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement".
>> GO TO 4.

4.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
>> GO TO 5.

5.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
>> END
Revision: 2007 June

EC-16

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL

MODULE)
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL
MODULE) : Description

EC

INFOID:0000000001830660

When replacing VVEL control module, this procedure must be performed.

ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL

MODULE) : Special Repair Requirement

INFOID:0000000001830661

1.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".

>> END

IDLE SPEED
F

IDLE SPEED : Description

INFOID:0000000001733911

This describes how to check the idle speed. For the actual procedure, follow the instructions in BASIC
INSPECTION.

IDLE SPEED : Special Repair Requirement

INFOID:0000000001733912

1.CHECK IDLE SPEED

With CONSULT-III
Check idle speed in DATA MONITOR mode with CONSULT-III.
With GST
Check idle speed with Service $01 of GST.

>> INSPECTION END

IGNITION TIMING

IGNITION TIMING : Description

INFOID:0000000001733913

This describes how to check the ignition timing. For the actual procedure, follow the instructions in BASIC
INSPECTION.

IGNITION TIMING : Special Repair Requirement

INFOID:0000000001733914

1.CHECK IGNITION TIMING

1.

Attach timing light to loop wire as shown.

N

JMBIA0846ZZ

1.

Loop wire

A.

Timing light

Revision: 2007 June

B.

Timing indicator

EC-17

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

2. Check ignition timing.
>> INSPECTION END

VIN REGISTRATION
VIN REGISTRATION : Description

INFOID:0000000001733915

VIN Registration is an operation to registering VIN in ECM. It must be performed each time ECM is replaced.
NOTE:
Accurate VIN which is registered in ECM may be required for Inspection & Maintenance (I/M).

VIN REGISTRATION : Special Repair Requirement

INFOID:0000000001733916

1.CHECK VIN
Check the VIN of the vehicle and note it. Refer to GI-20, "Information About Identification or Model Code".
>> GO TO 2.

2.PERFORM VIN REGISTRATION

1.
2.
3.

With CONSULT-III
Turn ignition switch ON and engine stopped.
Select VIN REGISTRATION in WORK SUPPORT mode.
Follow the instruction of CONSULT-III display.
>> END

ACCELERATOR PEDAL RELEASED POSITION LEARNING

ACCELERATOR PEDAL RELEASED POSITION LEARNING : Description

INFOID:0000000001733917

Accelerator Pedal Released Position Learning is a function of ECM to learn the fully released position of the
accelerator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each
time harness connector of accelerator pedal position sensor or ECM is disconnected.

ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement

INFOID:0000000001733918

1.START
1.
2.
3.
4.
5.

Make sure that accelerator pedal is fully released.

Turn ignition switch ON and wait at least 2 seconds.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON and wait at least 2 seconds.
Turn ignition switch OFF and wait at least 10 seconds.
>> END

THROTTLE VALVE CLOSED POSITION LEARNING

THROTTLE VALVE CLOSED POSITION LEARNING : Description

INFOID:0000000001733919

Throttle Valve Closed Position Learning is a function of ECM to learn the fully closed position of the throttle
valve by monitoring the throttle position sensor output signal. It must be performed each time harness connector of electric throttle control actuator or ECM is disconnected.

THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement

INFOID:0000000001733920

1.START
1.

Make sure that accelerator pedal is fully released.

Revision: 2007 June

EC-18

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]
< BASIC INSPECTION >
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
>> END

EC

IDLE AIR VOLUME LEARNING

IDLE AIR VOLUME LEARNING : Description

INFOID:0000000001733921

Idle Air Volume Learning is a function of ECM to learn the idle air volume that keeps engine idle speed within
the specific range. It must be performed under any of the following conditions:
Each time electric throttle control actuator or ECM is replaced.
Each time VVEL actuator sub assembly or VVEL control module is replaced.
Idle speed or ignition timing is out of specification.

IDLE AIR VOLUME LEARNING : Special Repair Requirement

INFOID:0000000001733922

1.PRECONDITIONING
Make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
Battery voltage: More than 12.9V (At idle)
Engine coolant temperature: 70 - 105C (158 - 221F)
PNP switch: ON
Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not be illuminated.
Steering wheel: Neutral (Straight-ahead position)
Vehicle speed: Stopped
Transmission: Warmed-up
- A/T models
With CONSULT-III: Drive vehicle until ATF TEMP SE 1 in DATA MONITOR mode of A/T system indicates less than 0.9V.
Without CONSULT-III: Drive vehicle for 10 minutes.
- M/T models
Drive vehicle for 10 minutes.
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.PERFORM IDLE AIR VOLUME LEARNING

With CONSULT-III
Perform Accelerator Pedal Released Position Learning. Refer to EC-18, "ACCELERATOR PEDAL
RELEASED POSITION LEARNING : Special Repair Requirement".
2. Perform Throttle Valve Closed Position Learning. EC-18, "THROTTLE VALVE CLOSED POSITION
LEARNING : Special Repair Requirement".
3. Start engine and warm it up to normal operating temperature.
4. Select IDLE AIR VOL LEARN in WORK SUPPORT mode.
5. Touch START and wait 20 seconds.
Is CMPLT displayed on CONSULT-III screen?
YES >> GO TO 4.
NO
>> GO TO 5.

1.

3.PERFORM IDLE AIR VOLUME LEARNING

Without CONSULT-III
NOTE:
It is better to count the time accurately with a clock.
It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
Revision: 2007 June

EC-19

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]
< BASIC INSPECTION >
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-18, "ACCELERATOR PEDAL
RELEASED POSITION LEARNING : Special Repair Requirement".
2. Perform Throttle Valve Closed Position Learning. EC-18, "THROTTLE VALVE CLOSED POSITION
LEARNING : Special Repair Requirement".
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
6. Repeat the following procedure quickly five times within 5 seconds.
Fully depress the accelerator pedal.
Fully release the accelerator pedal.
7. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops
blinking and turned ON.
8. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
9. Start engine and let it idle.
10. Wait 20 seconds.

SEC897C

>> GO TO 4.

4.CHECK IDLE SPEED AND IGNITION TIMING

1.
2.
3.

Start engine and warm it up to normal operating temperature.

Let it idle for 20 seconds.
Rev up the engine two or three times and make sure that idle speed and ignition timing are within the
specifications. Refer to EC-606, "Idle Speed" and EC-606, "Ignition Timing".
Is the inspection result normal?
YES >> INSPECTION END
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART-I

Check the following
Check that throttle valve is fully closed.
Check PCV valve operation.
Check that downstream of throttle valve is free from air leakage.
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair or replace malfunctioning part.

6.DETECT MALFUNCTIONING PART-II

Engine component parts and their installation condition are questionable. Check and eliminate the cause of
the incident.
It is useful to perform TROUBLE DIAGNOSIS - SPECIFICATION VALUE. Refer to EC-132, "Description".
If any of the following conditions occur after the engine has started, eliminate the cause of the incident and
perform Idle Air Volume Learning all over again:
Engine stalls.
Erroneous idle.
>> INSPECTION END

VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

Revision: 2007 June

EC-20

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Description

INFOID:0000000001736789

VVEL control shaft position sensor adjustment is an operation to adjust the initial position angle that is the
basis for the VVEL control shaft position sensor.
EC
It must be performed each time VVEL actuator sub assembly is replaced.
CAUTION:
It must be performed only on the replaced bank side.
It must not be performed except when VVEL actuator sub assembly is replaced. If by any chance the C
adjustment is performed, replace VVEL actuator sub assembly.

VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Special Repair Requirement

INFOID:0000000001736790

1.START

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

1.
2.
3.
4.
5.
6.
7.

With CONSULT-III
Turn ignition switch ON.
Select VVEL POS SEN ADJ PREP in WORK SUPPORT mode with CONSULT-III.
Touch Start and wait a few seconds.
Make sure the CMPLT is displayed on CONSULT-III screen.
Select VVEL POSITION SEN- B1 or VVEL POSITION SEN- B2 in DATA MONITOR mode with CONSULT-III.
Loosen the VVEL control shaft position sensor mounting bolt (1).
Turn the VVEL control shaft position sensor (2) right and left
while monitoring the output voltage of VVEL POSITION SENB1 or VVEL POSITION SEN-B2 and adjust the output voltage
to be within the standard value.
Voltage

8.

: 50048mV

Tighten the VVEL control shaft position sensor mounting bolt.

: 7.0 Nm (0.71kg-m, 62in-lb)

L
JMBIA0740ZZ

9.

Reconfirm that the output voltage of VVEL POSITION SEN- B1

or VVEL POSITION SEN- B2 is within the standard value.
Voltage

10.
11.
12.
13.

: 50048mV

NOTE:
If it varies from the standard value after the bolt is tightened, perform steps 6 to 8 again.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Perform idle air volume learning. Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair
Requirement".

>> INSPECTION END

3.PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

1.
2.
3.

Without CONSULT-III
Disconnect VVEL control shaft position sensor harness connector.
Remove VVEL actuator motor relay.
Turn ignition switch ON, wait at least 5 seconds and then turn OFF.

Revision: 2007 June

EC-21

G37 Coupe

INSPECTION AND ADJUSTMENT

[VQ37VHR]

< BASIC INSPECTION >

4. Reconnect all harness connectors disconnected.
5. Install VVEL actuator motor relay.
6. Turn ignition switch ON and wait at least 5 seconds.
7. Loosen the VVEL control shaft position sensor mounting bolt (1).
8. Turn the VVEL control shaft position sensor (2) right and left
while monitoring the output voltage between the VVEL control
module terminals with a tester and adjust the output voltage to
be within the standard value.

JMBIA0740ZZ

VVEL control module

Bank

Connector

Terminal

Terminal

E15

9.

Voltage

50048mV

Tighten the VVEL control shaft position sensor mounting bolt.

: 7.0 Nm (0.71kg-m, 62in-lb)

10. Reconfirm that the output voltage of VVEL control shaft position sensor is within the standard value.
VVEL control module
Bank

Connector

Terminal

Terminal

E15

11.
12.
13.
14.

Voltage

50048mV

NOTE:
If it varies from the standard value after the bolt is tightened, perform steps 7 to 9 again.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Perform idle air volume learning. Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair
Requirement".
>> INSPECTION END

MIXTURE RATIO SELF-LEARNING VALUE CLEAR

MIXTURE RATIO SELF-LEARNING VALUE CLEAR : Description

INFOID:0000000001733925

This describes how to erase the mixture ratio self-learning value. For the actual procedure, follow the instructions in Diagnosis Procedure.

MIXTURE RATIO SELF-LEARNING VALUE CLEAR : Special Repair Requirement

INFOID:0000000001733926

1.START
1.
2.

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Select SELF-LEARNING CONT in WORK SUPPORT mode with CONSULT-III.

Revision: 2007 June

EC-22

G37 Coupe

INSPECTION AND ADJUSTMENT

< BASIC INSPECTION >
3. Clear mixture ratio self-learning value by touching CLEAR.
With GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor (bank 1) harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor (bank 1) harness connector.
6. Select Service $03 with GST. Make sure DTC P0102 is detected.
7. Select Service $04 with GST to erase the DTC P0102.

[VQ37VHR]
A

EC

>> END

Revision: 2007 June

EC-23

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

FUNCTION DIAGNOSIS
ENGINE CONTROL SYSTEM
System Diagram

INFOID:0000000001733927

JMBIA0856ZZ

1.

ECM

Can communication

3.

VVEL control module

4.

EVAP canister purge volume control 5.

solenoid valve

2.

EVAP service port

6.

EVAP canister vent control valve

7.

EVAP control system pressure sensor

EVAP canister

9.

Battery current sensor

8.

10. Battery

11. Fuel tank temperature sensor

13. Fuel tank

14. Fuel pressure regulator

15. Fuel pump

16. Three way catalyst 2

17. Heated oxygen sensor 2

18. Three way catalyst 1

19. Engine oil temperature sensor

20. A/F sensor 1

21. Spark plug

22. PCV valve

23. Ignition coil (with power transistor)

24. VVEL actuator motor

Revision: 2007 June

EC-24

12. Fuel level sensor

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

25. VVEL control shaft position sensor

26. Intake valve timing control solenoid

valve

27. Camshaft position sensor (PHASE)

28. Fuel damper

29. Engine coolant temperature sensor

30. Knock sensor

31. Crankshaft position sensor (POS)

32. Muffler

33. Cooling fan control module

34. Cooling fan

35. PNP switch

36. Air cleaner

37. Mass air flow sensor (with intake air

temperature sensor)

38. Electric throttle control actuator

39. Throttle position sensor

40. Manifold absolute pressure (MAP)

sensor

41. Brake booster pressure sensor

42. MIL

43. Ignition switch

44. Accelerator pedal position sensor

45. Power steering pressure sensor

EC

46. Refrigerant pressure sensor

System Description

INFOID:0000000001733928

ECM performs various controls such as fuel injection control and ignition timing control.

Component Parts Location

INFOID:0000000001733929

P
JMBIA0837ZZ

1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

Revision: 2007 June

EC-25

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

31. Ignition coil (with power transistor)

and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

JMBIA0840ZZ

Revision: 2007 June

EC-26

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

2.

Cooling fan control module

3.

Cooling fan motor-1

EC

G
PBIB1907E

J
JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

Revision: 2007 June

2.

A/F sensor 1 (bank 2) harness connector

EC-27

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0018ZZ

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

JMBIA0850ZZ

1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

Revision: 2007 June

2.

VVEL actuator motor (bank 1)

EC-28

3.

VVEL actuator motor (bank 2)

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0842ZZ

D
1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

H
JMBIA0843ZZ

1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2

Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

N
JMBIA0844ZZ

O
: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

Revision: 2007 June

EC-29

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

JMBIA0845ZZ

: Vehicle front
1.

EVAP service port

2.

EVAP canister purge volume control 3.

solenoid valve

4.

EVAP canister vent control valve

5.

EVAP control system pressure sensor

EVAP canister

JMBIA0019ZZ

Revision: 2007 June

EC-30

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

EC

E
JMBIA0015ZZ

1.

Accelerator pedal position sensor

2.

ECM

I
JMBIA0016ZZ

1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

M
JMBIA0017ZZ

N
1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

JMBIA0051ZZ

Revision: 2007 June

EC-31

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733930

Component

Reference

A/F sensor 1

EC-197, "Description"

A/F sensor 1 heater

EC-155, "Description"

Accelerator pedal position sensor

EC-458, "Description"

ASCD brake switch

EC-428, "Description"

ASCD steering switch

EC-421, "Description"

ASCD vehicle speed sensor

EC-443, "Description"

Battery current sensor

EC-408, "Description"

Brake booster pressure sensor

EC-346, "Description"

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Cooling fan control module

EC-481, "Description"

Cooling fan motor

EC-481, "Description"

Electric throttle control actuator

EC-399, "Description"

Engine coolant temperature sensor

EC-184, "Description"

Engine oil temperature sensor

EC-246, "Description"

EVAP canister purge volume control solenoid valve

EC-288, "Description"

EVAP canister vent control valve

EC-296, "Description"

EVAP control system pressure sensor

EC-304, "Description"

Fuel injector

EC-487, "Description"

Fuel level sensor

EC-331, "Description"

Fuel pump

EC-490, "Description"

Fuel tank temperature sensor

EC-240, "Description"

Heated oxygen sensor 2

EC-212, "Description"

Heated oxygen sensor 2 heater

EC-158, "Description"

ICC brake switch

EC-435, "Description"

ICC steering switch

EC-424, "Description"

ICC vehicle speed sensor

EC-445, "Description"

Ignition signal

EC-498, "Description"

Intake air temperature sensor

EC-181, "Description"

Intake valve timing control solenoid valve

EC-162, "Description"

Knock sensor

EC-261, "Description"

Manifold absolute pressure (MAP) sensor

EC-177, "Description"

Mass air flow sensor

EC-165, "Description"

Park/neutral position switch

EC-361, "Description"

PCV valve

EC-509, "Description"

Power steering pressure sensor

EC-346, "Description"

Refrigerant pressure sensor

EC-511, "Description"

Stop lamp switch

EC-455, "Description"

Revision: 2007 June

EC-32

G37 Coupe

ENGINE CONTROL SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component

Reference

Throttle control motor

EC-396, "Description"

Throttle control motor relay

EC-404, "Description"

Throttle position sensor

EC-187, "Description"

Vehicle speed sensor

EC-337, "Description"

VVEL actuator motor

EC-374, "Description"

VVEL actuator motor relay

EC-378, "Description"

VVEL control module

EC-447, "Description"

VVEL control shaft position sensor

EC-370, "Description"

EC

Revision: 2007 June

EC-33

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

MULTIPORT FUEL INJECTION SYSTEM

System Diagram

INFOID:0000000001733931

JMBIA0071GB

System Description

INFOID:0000000001733932

INPUT/OUTPUT SIGNAL CHART

Sensor
Crankshaft position sensor (POS)

Input Signal to ECM

Camshaft position sensor (PHASE)

Engine speed*3
Piston position

Mass air flow sensor

Amount of intake air

Intake air temperature sensor

Intake air temperature

Engine coolant temperature sensor

Engine coolant temperature

Air fuel ratio (A/F) sensor 1

Density of oxygen in exhaust gas

Throttle position sensor

Throttle position

Accelerator pedal position sensor

Accelerator pedal position

Park/neutral position (PNP) switch

Gear position

Battery

Battery voltage*3

Knock sensor

Engine knocking condition

Power steering pressure sensor

Power steering operation

Heated oxygen sensor 2*1

Density of oxygen in exhaust gas

ABS actuator and electric unit (control unit)*2

VDC/TCS operation command

Unified meter and A/C amp.

ECM function

Fuel injection
& mixture ratio
control

Actuator

Fuel injector

Air conditioner operation*2

Vehicle speed*2

*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.

Revision: 2007 June

EC-34

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

*3: ECM determines the start signal status by the signals of engine speed and battery voltage.

SYSTEM DESCRIPTION

The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined EC
by input signals (for engine speed and intake air) from the crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the mass air flow sensor.
C
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operating conditions as listed below.
D
<Fuel increase>

During warm-up
When starting the engine
During acceleration
Hot-engine operation
When selector lever is changed from N to D (A/T models)
High-load, high-speed operation

<Fuel decrease>

During deceleration
During high engine speed operation

MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)

H

J
PBIB2793E

The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst 1 can then better reduce CO, HC and NOx emissions. This system uses A/F sensor 1
in the exhaust manifold to monitor whether the engine operation is rich or lean. The ECM adjusts the injection
pulse width according to the sensor voltage signal. For more information about A/F sensor 1, refer to EC-197,
"Description". This maintains the mixture ratio within the range of stoichiometric (ideal air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst 1. Even if the switching characteristics of A/F sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal from heated oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.
- Deceleration and acceleration
- High-load, high-speed operation
- Malfunction of A/F sensor 1 or its circuit
- Insufficient activation of A/F sensor 1 at low engine coolant temperature
- High engine coolant temperature
- During warm-up
- After shifting from N to D (A/T models)
- When starting the engine

MIXTURE RATIO SELF-LEARNING CONTROL

The mixture ratio feedback control system monitors the mixture ratio signal transmitted from A/F sensor 1.
This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to the theoretical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as originally
designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic changes during operation (i.e., fuel injector clogging) directly affect mixture ratio.
Revision: 2007 June

EC-35

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of injection pulse duration to automatically compensate for the difference between
the two ratios.
Fuel trim refers to the feedback compensation value compared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
Short term fuel trim is the short-term fuel compensation used to maintain the mixture ratio at its theoretical
value. The signal from A/F sensor 1 indicates whether the mixture ratio is RICH or LEAN compared to the theoretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and an increase in
fuel volume if it is lean.
Long term fuel trim is overall fuel compensation carried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.

FUEL INJECTION TIMING

SEF179U

Two types of systems are used.

Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycle according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all six cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The six injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.

FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or operation of the vehicle at excessively high speeds.

Revision: 2007 June

EC-36

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910704

EC

K
JMBIA0837ZZ

L
1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-37

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

JMBIA0840ZZ

: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

Revision: 2007 June

2.

Cooling fan control module

EC-38

3.

Cooling fan motor-1

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

E
PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

M
JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-39

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

JMBIA0850ZZ

1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-40

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0843ZZ

D
1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

N
JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-41

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

JMBIA0845ZZ

: Vehicle front
1.

EVAP service port

2.

EVAP canister purge volume control 3.

solenoid valve

4.

EVAP canister vent control valve

5.

EVAP control system pressure sensor

EVAP canister

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

Revision: 2007 June

2.

ECM

EC-42

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0016ZZ

D
1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

L
JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733934

O
Component

Reference

A/F sensor 1

EC-197, "Description"

Accelerator pedal position sensor

EC-458, "Description"

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Engine coolant temperature sensor

EC-184, "Description"

Fuel injector

EC-487, "Description"

Heated oxygen sensor 2

EC-212, "Description"

Revision: 2007 June

EC-43

G37 Coupe

MULTIPORT FUEL INJECTION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component

Reference

Intake air temperature sensor

EC-181, "Description"

Knock sensor

EC-261, "Description"

Mass air flow sensor

EC-165, "Description"

Park/neutral position switch

EC-361, "Description"

Power steering pressure sensor

EC-346, "Description"

Throttle position sensor

EC-187, "Description"

Vehicle speed sensor

EC-337, "Description"

Revision: 2007 June

EC-44

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

ELECTRIC IGNITION SYSTEM

System Diagram

INFOID:0000000001733935

EC

F
JMBIA0072GB

System Description

INFOID:0000000001733936

INPUT/OUTPUT SIGNAL CHART

Sensor
Crankshaft position sensor (POS)

Input Signal to ECM

Camshaft position sensor (PHASE)

Engine speed*2
Piston position

Mass air flow sensor

Amount of intake air

Engine coolant temperature sensor

Engine coolant temperature

Throttle position sensor

Throttle position

Accelerator pedal position sensor

Accelerator pedal position

Park/neutral position (PNP) switch

Gear position

Battery

Battery voltage*2

Knock sensor

Engine knocking

Unified meter and A/C amp.

Vehicle speed*1

ECM function

Actuator

J
Ignition timing
control

Ignition coil (with power transistor)

*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.

SYSTEM DESCRIPTION
Firing order: 1 - 2 - 3 - 4 - 5 - 6
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor (PHASE) signal. Computing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised by the ECM according to the other data stored in
the ECM.
At starting
During warm-up
At idle
At low battery voltage
During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
Revision: 2007 June

EC-45

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.

Component Parts Location

INFOID:0000000001910703

JMBIA0837ZZ

1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-46

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

EC

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

I
JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

M
JMBIA0840ZZ

N
: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

2.

Cooling fan control module

3.

Cooling fan motor-1

Revision: 2007 June

EC-47

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-48

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

EC

E
JMBIA0850ZZ

F
1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

J
JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

O
JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-49

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0843ZZ

1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-50

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

EC

JMBIA0845ZZ

: Vehicle front
1.
4.

EVAP service port

EVAP canister vent control valve

2.
5.

EVAP canister purge volume control 3.

solenoid valve

EVAP canister

EVAP control system pressure sensor

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

2.

ECM

Revision: 2007 June

EC-51

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0016ZZ

1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733938

Component

Reference

Accelerator pedal position sensor

EC-458, "Description"

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Engine coolant temperature sensor

EC-184, "Description"

Ignition signal

EC-498, "Description"

Knock sensor

EC-261, "Description"

Mass air flow sensor

EC-165, "Description"

Revision: 2007 June

EC-52

G37 Coupe

ELECTRIC IGNITION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component

Reference

Park/neutral position switch

EC-361, "Description"

Throttle position sensor

EC-187, "Description"

Vehicle speed sensor

EC-337, "Description"

EC

Revision: 2007 June

EC-53

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

AIR CONDITIONING CUT CONTROL

System Diagram

INFOID:0000000001733939

JMBIA0073GB

System Description

INFOID:0000000001733940

INPUT/OUTPUT SIGNAL CHART

Sensor

Input Signal to ECM

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)

Engine speed*2

Engine coolant temperature sensor

Engine coolant temperature

Accelerator pedal position sensor

Accelerator pedal position

Battery

Battery voltage*2

Refrigerant pressure sensor

Refrigerant pressure

Power steering pressure sensor

Power steering operation

Unified meter and A/C amp.

ECM function

Air conditioner
cut control

Actuator

IPDM E/R

A/C relay

Compressor

Air conditioner ON signal*1

Vehicle speed*1

*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.

SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
When the accelerator pedal is fully depressed.
When cranking the engine.
At high engine speeds.
When the engine coolant temperature becomes excessively high.
When operating power steering during low engine speed or low vehicle speed.
When engine speed is excessively low.
When refrigerant pressure is excessively low or high.

Revision: 2007 June

EC-54

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910706

EC

K
JMBIA0837ZZ

L
1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-55

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

JMBIA0840ZZ

: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

Revision: 2007 June

2.

Cooling fan control module

EC-56

3.

Cooling fan motor-1

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

E
PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

M
JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-57

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

JMBIA0850ZZ

1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-58

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0843ZZ

D
1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

N
JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-59

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

JMBIA0845ZZ

: Vehicle front
1.

EVAP service port

2.

EVAP canister purge volume control 3.

solenoid valve

4.

EVAP canister vent control valve

5.

EVAP control system pressure sensor

EVAP canister

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

Revision: 2007 June

2.

ECM

EC-60

G37 Coupe

AIR CONDITIONING CUT CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0016ZZ

D
1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

L
JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733942

O
Component

Reference

Accelerator pedal position sensor

EC-458, "Description"

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Engine coolant temperature sensor

EC-184, "Description"

Power steering pressure sensor

EC-346, "Description"

Refrigerant pressure sensor

EC-511, "Description"

Vehicle speed sensor

EC-337, "Description"

Revision: 2007 June

EC-61

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

System Diagram

INFOID:0000000001733943

JMBIA0074GB

System Description

INFOID:0000000001733944

INPUT/OUTPUT SIGNAL CHART

Sensor
ASCD brake switch

Input signal to ECM

ECM function

Actuator

Brake pedal operation

Stop lamp switch

Brake pedal operation

ASCD clutch switch (M/T models)

Clutch pedal operation

ASCD steering switch

ASCD steering switch operation

Park/neutral position (PNP) switch

Gear position

Unified meter and A/C amp.

Vehicle speed*

TCM (A/T models)

Powertrain revolution*

ASCD vehicle speed control

Electric throttle control

actuator

*: This signal is sent to the ECM through CAN communication line

BASIC ASCD SYSTEM

Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric throttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE lamp and SET lamp in combination meter. If any malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.

SET OPERATION
Press MAIN switch. (The CRUISE lamp in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET lamp in combination meter illuminates.)

ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.

CANCEL OPERATION
Revision: 2007 June

EC-62

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]
< FUNCTION DIAGNOSIS >
When any of following conditions exist, cruise operation will be canceled.
CANCEL switch is pressed
A
More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
Brake pedal is depressed
Clutch pedal is depressed or gear position is changed to neutral position. (M/T models)
EC
Selector lever is changed to N, P, R position (A/T models)
Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
TCS system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform C
the driver by blinking indicator lamp.
Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
D
When the engine coolant temperature decreases to the normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
E
Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
F

COAST OPERATION
When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.

RESUME OPERATION
When the RESUME/ACCELERATE switch is pressed after cancel operation other than pressing MAIN switch
is performed, vehicle speed will return to last set speed. To resume vehicle set speed, vehicle condition must
meet following conditions.
Brake pedal is released
Clutch pedal is released (M/T models)
A/T selector lever is in other than P and N positions (A/T models)
Vehicle speed is greater than 40 km/h (25 MPH) and less than 144 km/h (89 MPH)

Revision: 2007 June

EC-63

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910705

JMBIA0837ZZ

1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-64

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

EC

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

I
JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

M
JMBIA0840ZZ

N
: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

2.

Cooling fan control module

3.

Cooling fan motor-1

Revision: 2007 June

EC-65

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-66

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

EC

E
JMBIA0850ZZ

F
1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

J
JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

O
JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-67

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0843ZZ

1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-68

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

EC

JMBIA0845ZZ

: Vehicle front
1.
4.

EVAP service port

EVAP canister vent control valve

2.
5.

EVAP canister purge volume control 3.

solenoid valve

EVAP canister

EVAP control system pressure sensor

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

2.

ECM

Revision: 2007 June

EC-69

G37 Coupe

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0016ZZ

1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)
Clutch pedal

Component Description

INFOID:0000000001733946

Component

Reference

ASCD steering switch

EC-421, "Description"

ASCD brake switch

EC-428, "Description"

Stop lamp switch

EC-428, "Description"

Electric throttle control actuator

EC-404, "Description"

ASCD indicator

EC-480, "Description"

Revision: 2007 June

Brake pedal

EC-70

G37 Coupe

CAN COMMUNICATION
[VQ37VHR]

< FUNCTION DIAGNOSIS >

CAN COMMUNICATION

System Description

INFOID:0000000001733947

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul- EC
tiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring. C
Each control unit transmits/receives data but selectively reads required data only.
Refer to LAN-8, "CAN Communication Control Circuit", about CAN communication for detail..
D

Revision: 2007 June

EC-71

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

COOLING FAN CONTROL

System Diagram

INFOID:0000000001733948

JMBIA0075GB

System Description

INFOID:0000000001733949

INPUT/OUTPUT SIGNAL CHART

Sensor

Input signal to ECM

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)

Engine speed*1

Engine coolant temperature sensor

Engine coolant temperature

Refrigerant pressure sensor

Refrigerant pressure

Battery

Battery voltage*1
Vehicle speed*

Unified meter and A/C amp.

ECM function

Cooling fan
control

Air conditioner ON signal*2

Actuator

IPDM E/R

Cooling fan control module

Cooling fan motor

A/C evaporator temperature*2

Target A/C evaporator temperature*2

*1: The ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to ECM through CAN communication line.

SYSTEM DESCRIPTION
ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, air conditioner
ON signal, refrigerant pressure, target A/C evaporator temperature and A/C evaporator temperature.
Cooling fan control signal is sent to IPDM E/R from ECM by CAN communication line. Then, IPDM E/R sends
ON/OFF pulse duty signal to cooling fan control module. Corresponding to this ON/OFF pulse duty signal,
cooling fan control module gives cooling fan motor operating voltage to cooling fan motors. Cooling fan speed
is controlled by duty cycle of cooling fan motor operating voltage sent from cooling fan control module.

Revision: 2007 June

EC-72

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910707

EC

K
JMBIA0837ZZ

L
1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-73

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

JMBIA0840ZZ

: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

Revision: 2007 June

2.

Cooling fan control module

EC-74

3.

Cooling fan motor-1

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

E
PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

M
JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-75

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

JMBIA0850ZZ

1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-76

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0843ZZ

D
1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

N
JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-77

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

JMBIA0845ZZ

: Vehicle front
1.

EVAP service port

2.

EVAP canister purge volume control 3.

solenoid valve

4.

EVAP canister vent control valve

5.

EVAP control system pressure sensor

EVAP canister

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

Revision: 2007 June

2.

ECM

EC-78

G37 Coupe

COOLING FAN CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0016ZZ

D
1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

L
JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733951

O
Component

Reference

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Cooling fan control module

EC-481, "Description"

Cooling fan motor

EC-481, "Description"

Engine coolant temperature sensor

EC-184, "Description"

Refrigerant pressure sensor

EC-511, "Description"

Revision: 2007 June

EC-79

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EVAPORATIVE EMISSION SYSTEM

System Diagram

INFOID:0000000001733952

PBIB1631E

EVAPORATIVE EMISSION LINE DRAWING

JMBIA0859ZZ

1.

Intake manifold collector

2.

EVAP canister purge volume control 3.

solenoid valve

EVAP service port

: From next figure

Revision: 2007 June

EC-80

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

JMBIA0847ZZ

: Vehicle front
1.

EVAP canister

2.

EVAP canister vent control valve

3.

EVAP control system pressure sensor

: To previous figure

NOTE:
Do not use soapy water or any type of solvent while installing vacuum hose or purge hoses.

System Description

INFOID:0000000001733953

INPUT/OUTPUT SIGNAL CHART

O

Revision: 2007 June

EC-81

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Sensor

Input signal to ECM

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)

Engine speed*1

Mass air flow sensor

Amount of intake air

Engine coolant temperature sensor

Engine coolant temperature

Battery

Battery voltage*1

Throttle position sensor

Throttle position

Accelerator pedal position sensor

Accelerator pedal position

Air fuel ratio (A/F) sensor 1

Density of oxygen in exhaust gas

(Mixture ratio feedback signal)

Fuel tank temperature sensor

Fuel temperature in fuel tank

EVAP control system pressure sensor

Pressure in purge line

Unified meter and A/C amp.

Vehicle speed*2

ECM function

Actuator

EVAP canister
purge flow control

EVAP canister purge volume control solenoid valve

*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.

SYSTEM DESCRIPTION
The evaporative emission system is used to reduce hydrocarbons emitted into the atmosphere from the fuel
system. This reduction of hydrocarbons is accomplished by activated charcoals in the EVAP canister.
The fuel vapor in the sealed fuel tank is led into the EVAP canister which contains activated carbon and the
vapor is stored there when the engine is not operating or when refueling to the fuel tank.
The vapor in the EVAP canister is purged by the air through the purge line to the intake manifold when the
engine is operating. EVAP canister purge volume control solenoid valve is controlled by ECM. When the
engine operates, the flow rate of vapor controlled by EVAP canister purge volume control solenoid valve is
proportionally regulated as the air flow increases.
EVAP canister purge volume control solenoid valve also shuts off the vapor purge line during decelerating and
idling.

Revision: 2007 June

EC-82

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910708

EC

K
JMBIA0837ZZ

L
1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-83

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

JMBIA0840ZZ

: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

Revision: 2007 June

2.

Cooling fan control module

EC-84

3.

Cooling fan motor-1

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

E
PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

M
JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-85

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

JMBIA0850ZZ

1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-86

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0843ZZ

D
1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

N
JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-87

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

JMBIA0845ZZ

: Vehicle front
1.

EVAP service port

2.

EVAP canister purge volume control 3.

solenoid valve

4.

EVAP canister vent control valve

5.

EVAP control system pressure sensor

EVAP canister

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

Revision: 2007 June

2.

ECM

EC-88

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

C
JMBIA0016ZZ

D
1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

L
JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733955

O
Component

Reference

A/F sensor 1

EC-197, "Description"

Accelerator pedal position sensor

EC-458, "Description"

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Engine coolant temperature sensor

EC-184, "Description"

EVAP canister purge volume control solenoid valve

EC-288, "Description"

EVAP control system pressure sensor

EC-304, "Description"

Revision: 2007 June

EC-89

G37 Coupe

EVAPORATIVE EMISSION SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component

Reference

Fuel tank temperature sensor

EC-240, "Description"

Mass air flow sensor

EC-165, "Description"

Throttle position sensor

EC-187, "Description"

Vehicle speed sensor

EC-337, "Description"

Revision: 2007 June

EC-90

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

INTAKE VALVE TIMING CONTROL

System Diagram

INFOID:0000000001733960

EC

F
JMBIA0060GB

System Description

INFOID:0000000001733961

INPUT/OUTPUT SIGNAL CHART

Sensor
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Input signal to ECM

ECM function

Actuator

I
Engine speed and piston position

Engine coolant temperature sensor

Engine coolant temperature

Unified meter and A/C amp.

Vehicle speed*

Intake valve
timing control

Intake valve timing control

solenoid valve

*: This signal is sent to the ECM through CAN communication line

SYSTEM DESCRIPTION
This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty signals to the intake valve timing (IVT) control solenoid valve depending on driving status. This makes it possible to control the shut/open timing of the intake
valve to increase engine torque in low/mid speed range and output in high-speed range.

Revision: 2007 June

EC-91

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910709

JMBIA0837ZZ

1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-92

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

EC

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

I
JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

M
JMBIA0840ZZ

N
: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

2.

Cooling fan control module

3.

Cooling fan motor-1

Revision: 2007 June

EC-93

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-94

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

EC

E
JMBIA0850ZZ

F
1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

J
JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

O
JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-95

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0843ZZ

1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-96

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

EC

JMBIA0845ZZ

: Vehicle front
1.
4.

EVAP service port

EVAP canister vent control valve

2.
5.

EVAP canister purge volume control 3.

solenoid valve

EVAP canister

EVAP control system pressure sensor

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

2.

ECM

Revision: 2007 June

EC-97

G37 Coupe

INTAKE VALVE TIMING CONTROL

[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0016ZZ

1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001733963

Component

Reference

Camshaft position sensor (PHASE)

EC-268, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

Engine coolant temperature sensor

EC-184, "Description"

Intake valve timing control solenoid valve

EC-162, "Description"

Vehicle speed sensor

EC-337, "Description"

Revision: 2007 June

EC-98

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

VVEL SYSTEM

System Diagram

INFOID:0000000001841366

EC

G
JMBIA0739GB

1.

VVEL actuator motor

2.

VVEL control shaft position sensor

3.

Ball screw nut

4.

Ball screw shaft

5.

Rocker arm

6.

Link A

7.

Control shaft

8.

Eccentric cam

9.

Drive shaft

10. Valve lifter

11. Intake valve

12. Link B

13. Output cam

System Description

INFOID:0000000001841367

INPUT/OUTPUT SIGNAL CHART

Sensor

Input signal to ECM

Crankshaft position sensor (POS)

Engine speed and piston position

Accelerator pedal position sensor

Accelerator pedal position

VVEL control shaft position sensor

Control shaft actual angle*

ECM function

VVEL control

Actuator

VVEL control module

VVEL actuator sub assembly

*: This signal is sent to the ECM through CAN communication line

SYSTEM DESCRIPTION
VVEL (Variable Valve Event & Lift) is a system that controls valve event and valve lift continuously. Rotational
movement of the drive shaft equipped with eccentric cam is transmitted to output cam via the rocker arm and
two kinds of links to depress the intake valve. ECM decides the target valve lift according to the driving condition and sends the command signal to the VVEL control module. The VVEL control module controls the rotation of the control shaft using the VVEL actuator motor and changes the movement of the output cam by
shifting the link supporting point. As a result, valve lift changes continuously to improve engine output and
response.

Revision: 2007 June

EC-99

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

Component Parts Location

INFOID:0000000001910710

JMBIA0837ZZ

1.

Battery current sensor

2.

IPDM E/R

3.

VVEL control module

4.

Cooling fan relay

5.

VVEL actuator motor relay

6.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

7.

Refrigerant pressure sensor

8.

Camshaft position sensor (PHASE)

(bank 1)

9.

Cooling fan motor-2

10. Intake valve timing control solenoid

valve (bank 1)

11. Cooling fan control module

12. Cooling fan motor-1

13. Intake valve timing control solenoid

valve (bank 2)

14. Camshaft position sensor (PHASE)

(bank 2)

15. Mass air flow sensor (with intake air

temperature sensor) (bank 2)

16. ICC brake hold relay (ICC models)

17. Brake booster pressure sensor

18. Ignition coil (with power transistor)

and spark plug (bank 2)

19. Electric throttle control actuator

(bank 2)

20. A/F sensor 1 (bank 2)

21. Fuel injector (bank 2)

22. VVEL control shaft position sensor

(bank 2)

23. VVEL actuator motor (bank 2)

24. Manifold absolute pressure (MAP)

sensor

25. Engine coolant temperature sensor

26. Knock sensor

27. Fuel injector (bank 1)

28. VVEL actuator motor (bank 1)

29. EVAP canister purge volume control 30. VVEL control shaft position sensor
solenoid valve
(bank 1)

Revision: 2007 June

EC-100

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

31. Ignition coil (with power transistor)
and spark plug (bank 1)

32. EVAP service port

34. Crankshaft position sensor (POS)

35. Electric throttle control actuator

(bank 1)

33. A/F sensor 1 (bank 1)

EC

JMBIA0838ZZ

1.

Mass air flow sensor (with intake air

temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air

temperature sensor) (bank 2)

I
JMBIA0839ZZ

1.

Electric throttle control actuator

(bank 1)

2.

Electric throttle control actuator

(bank 2)

M
JMBIA0840ZZ

N
: Vehicle front
1.

Cooling fan motor-2

4.

Cooling fan relay

2.

Cooling fan control module

3.

Cooling fan motor-1

Revision: 2007 June

EC-101

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

PBIB1907E

JMBIA0007ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

JMBIA0841ZZ

: Vehicle front
1.

A/F sensor 1 (bank 1) harness connector

2.

A/F sensor 1 (bank 2) harness connector

JMBIA0018ZZ

Revision: 2007 June

EC-102

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Heated oxygen sensor 2 (bank 2)

4.

Heated oxygen sensor 2 (bank 1)

harness connector

2.

Heated oxygen sensor 2 (bank 2)

harness connector

3.

Heated oxygen sensor 2 (bank 1)

EC

E
JMBIA0850ZZ

F
1.

Manifold absolute pressure (MAP)

sensor

4.

VVEL control module

2.

Brake booster pressure sensor

3.

VVEL actuator motor relay

J
JMBIA0851ZZ

1.

VVEL control shaft position sensor

(bank 1)

4.

VVEL control shaft position sensor

(bank 2)

2.

VVEL actuator motor (bank 1)

3.

VVEL actuator motor (bank 2)

O
JMBIA0842ZZ

1.

Camshaft position sensor (PHASE)

(bank 1)

4.

Camshaft position sensor (PHASE)

(bank 2)

Revision: 2007 June

2.

Intake valve timing control solenoid

valve (bank 1) harness connector

EC-103

3.

Intake valve timing control solenoid

valve (bank 2) harness connector

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0843ZZ

1.

Ignition coil No.5 (with power transis- 2.

tor)

Ignition coil No.3 (with power transis- 3.

tor)

4.

Fuel injector No.3

5.

Fuel injector No.1

7.

Fuel injector No.4

8.

Ignition coil No.2 (with power transis- 9.

tor)

10. Ignition coil No.6 (with power transis- 11. Fuel injector No.6
tor)
13. Knock sensor (bank 1)

6.

Ignition coil No.1 (with power transistor)

Fuel injector No.2
Ignition coil No.4 (with power transistor)

12. Fuel injector No.5

14. Knock sensor (bank 2)

JMBIA0844ZZ

: Vehicle front
1.

Engine coolant temperature sensor

2.

A/F sensor 1 (bank 1)

3.

Crankshaft position sensor (POS)

JMBIA0013ZZ

1.

IPDM E/R

2.

Battery current sensor

3.

Refrigerant pressure sensor

JMBIA0014ZZ

Revision: 2007 June

EC-104

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

: Vehicle front
1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

EC

JMBIA0845ZZ

: Vehicle front
1.
4.

EVAP service port

EVAP canister vent control valve

2.
5.

EVAP canister purge volume control 3.

solenoid valve

EVAP canister

EVAP control system pressure sensor

JMBIA0019ZZ

: Vehicle front
1.

Fuel level sensor unit and fuel pump 2.

harness connector

4.

Fuel tank temperature sensor

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

JMBIA0015ZZ

1.

Accelerator pedal position sensor

2.

ECM

Revision: 2007 June

EC-105

G37 Coupe

VVEL SYSTEM
[VQ37VHR]

< FUNCTION DIAGNOSIS >

JMBIA0016ZZ

1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

JMBIA0017ZZ

1.

ASCD steering switch

2.

CANCEL switch

4.

SET/COAST switch

5.

MAIN switch

3.

RESUME/ACCELERATE switch

JMBIA0051ZZ

1.

Stop lamp switch

2.

4.

ASCD clutch switch (ASCD models) 5.

ICC clutch switch (ICC models)

ASCD brake switch (ASCD models) 3.

ICC brake switch (ICC models)

Brake pedal

Clutch pedal

Component Description

INFOID:0000000001841369

Component

Reference

Accelerator pedal position sensor

EC-458, "Description"

Crankshaft position sensor (POS)

EC-264, "Description"

VVEL actuator motor

EC-374, "Description"

VVEL actuator motor relay

EC-378, "Description"

VVEL control module

EC-447, "Description"

VVEL control shaft position sensor

EC-370, "Description"

Revision: 2007 June

EC-106

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

ON BOARD DIAGNOSTIC (OBD) SYSTEM

Diagnosis Description

INFOID:0000000001733964

INTRODUCTION

EC

The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actuators. The ECM also records various emission-related diagnostic information including:
C
Emission-related diagnostic information

Diagnostic service

Diagnostic Trouble Code (DTC)

Service $03 of SAE J1979

Freeze Frame data

Service $02 of SAE J1979

System Readiness Test (SRT) code

Service $01 of SAE J1979

1st Trip Diagnostic Trouble Code (1st Trip DTC)

Service $07 of SAE J1979

1st Trip Freeze Frame data

Test values and Test limits

Service $06 of SAE J1979

Calibration ID

Service $09 of SAE J1979

The above information can be checked using procedures listed in the table below.
: Applicable : Not applicable

DTC

1st trip DTC

Freeze
Frame data

1st trip Freeze

Frame data

SRT code

SRT status

Test value

CONSULT-III

GST

ECM

*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.

The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode. (Refer to EC-548,
"Fail Safe".)

TWO TRIP DETECTION LOGIC

When a malfunction is detected for the first time, 1st trip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The trip in the Two Trip Detection Logic means a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic items will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.

: Applicable : Not applicable

MIL

DTC

1st trip

Items

2nd trip

1st trip DTC

1st trip
displaying

2nd trip
displaying

1st trip
displaying

2nd trip
displaying

Blinking

Lighting
up

Blinking

Lighting
up

Misfire (Possible three way catalyst

damage) DTC: P0300 - P0306 is
being detected

Misfire (Possible three way catalyst

damage) DTC: P0300 - P0306 is
being detected

One trip detection diagnoses (Refer to EC-552, "DTC Index".)

Except above

DTC AND FREEZE FRAME DATA

DTC and 1st Trip DTC

Revision: 2007 June

EC-107

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunction is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are stored in the ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL lights up when the same malfunction occurs in two consecutive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. For malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
Procedures for clearing the DTC and the 1st trip DTC from the ECM memory are described in HOW TO
ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION.
For malfunctions in which 1st trip DTCs are displayed, refer to EMISSION-RELATED DIAGNOSTIC INFORMATION ITEMS. These items are required by legal regulations to continuously monitor the system/component. In addition, the items monitored non-continuously are also displayed on CONSULT-III.
1st trip DTC is specified in Service $07 of SAE J1979. 1st trip DTC detection occurs without lighting up the MIL
and therefore does not warn the driver of a malfunction. However, 1st trip DTC detection will not prevent the
vehicle from being tested, for example during Inspection/Maintenance (I/M) tests.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step 2, refer to EC-9, "Work Flow". Then perform DTC Confirmation
Procedure or Component Function Check to try to duplicate the malfunction. If the malfunction is duplicated,
the item requires repair.
Freeze Frame Data and 1st Trip Freeze Frame Data
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant temperature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-III screen, not on the GST.
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the following priorities to update the data.
Priority
1

Items
Freeze frame data

2
3

Misfire DTC: P0300 - P0306

Fuel Injection System Function DTC: P0171, P0172, P0174, P0175
Except the above items (Includes A/T related items)

1st trip freeze frame data

For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different malfunction is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM memory is erased. Procedures for clearing the ECM memory are described in HOW TO ERASE EMISSIONRELATED DIAGNOSTIC INFORMATION.
How to Read DTC and 1st Trip DTC
With CONSULT-III
With GST
CONSULT-III or GST (Generic Scan Tool) Examples: P0340, P0850, P1148, etc.
These DTCs are prescribed by SAE J2012.

Revision: 2007 June

EC-108

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
(CONSULT-III also displays the malfunctioning component or system.)
A
No Tools
The number of blinks of the MIL in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0340, 0850, 1148, etc.
These DTCs are controlled by NISSAN.
EC
1st trip DTC No. is the same as DTC No.
Output of a DTC indicates a malfunction. However, GST or the Diagnostic Test Mode II do not indicate whether the malfunction is still occurring or has occurred in the past and has returned to normal. CONSULT-III can identify malfunction status as shown below. Therefore, using CONSULT-III (if C
available) is recommended.
DTC or 1st trip DTC of a malfunction is displayed in SELF-DIAGNOSTIC RESULTS mode of CONSULT-III.
Time data indicates how many times the vehicle was driven after the last detection of a DTC.
D
If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
How to Erase DTC and 1st Trip DTC
With CONSULT-III
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. The emission related diagnostic information in the ECM can be erased by selecting All Erase in the
Description of FINAL CHECK mode with CONSULT-III.
With GST
The emission related diagnostic information in the ECM can be erased by selecting Service $04 with GST.
NOTE:
If the DTC is not for A/T related items (see EC-552, "DTC Index"), skip step 2.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. Perform TM-108, "Diagnosis Description". (The DTC in TCM will be erased)
3. Select Service $04 with GST (Generic Scan Tool).
No Tools
NOTE:
If the DTC is not for A/T related items (see EC-552, "DTC Index"), skip step 2.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Perform TM-108, "Diagnosis Description". (The DTC in the TCM will be erased.)
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal.
If the battery is disconnected, the emission-related diagnostic information will be lost within 24
hours.
The following data are cleared when the ECM memory is erased.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
Actual work procedures are explained using a DTC as an example. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.

SYSTEM READINESS TEST (SRT) CODE

System Readiness Test (SRT) code is specified in Service $01 of SAE J1979.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and components. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating INCMP, use
the information in this Service Manual to set the SRT to CMPLT.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate CMPLT for each application system. Once set as CMPLT, the SRT status remains
CMPLT until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate INCMP for these items.
NOTE:
Revision: 2007 June

EC-109

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
The SRT will also indicate INCMP if the self-diagnosis memory is erased for any reason or if the ECM memory power supply is interrupted for several hours.
If, during the state emissions inspection, the SRT indicates CMPLT for all test items, the inspector will continue with the emissions test. However, if the SRT indicates INCMP for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MIL is ON during the state emissions inspection, the vehicle is also returned to the customer untested even
though the SRT indicates CMPLT for all test items. Therefore, it is important to check SRT (CMPLT) and
DTC (No DTCs) before the inspection.
SRT Item
The table below shows required self-diagnostic items to set the SRT to CMPLT.
SRT item
(CONSULT-III indication)

Performance
Priority*

Corresponding
DTC No.

Required self-diagnostic items to set the SRT to CMPLT

CATALYST

Three way catalyst function

P0420, P0430

EVAP SYSTEM

EVAP control system purge flow monitoring

P0441

EVAP control system

P0442

EVAP control system

P0456

Air fuel ratio (A/F) sensor 1

P0133, P0153

Heated oxygen sensor 2

P0137, P0157

Heated oxygen sensor 2

P0138, P0158

Heated oxygen sensor 2

P0139, P0159

HO2S

*: If completion of several SRTs is required, perform driving patterns (DTC confirmation procedure), one by one based on the priority for
models with CONSULT-III.

SRT Set Timing

SRT is set as CMPLT after self-diagnosis has been performed one or more times. Completion of SRT is
done regardless of whether the result is OK or NG. The set timing is different between OK and NG results and
is shown in the table below.
Example
Self-diagnosis result
All OK

Case 1

Case 2

NG exists

Case 3

Diagnosis

ON OFF

Ignition cycle
ON OFF ON OFF

ON

P0400

OK (1)

(1)

OK (2)

(2)

P0402

OK (1)

(1)

(1)

OK (2)

P1402

OK (1)

OK (2)

(2)

(2)

SRT of EGR

CMPLT

CMPLT

CMPLT

CMPLT

P0400

OK (1)

(1)

(1)

(1)

P0402

(0)

(0)

OK (1)

(1)

P1402

OK (1)

OK (2)

(2)

(2)

SRT of EGR

INCMP

INCMP

CMPLT

CMPLT

P0400

OK

OK

P0402

P1402

NG

NG

NG
(Consecutive
NG)

(1st trip)
DTC

1st trip DTC

1st trip DTC

DTC
(= MIL ON)

SRT of EGR

INCMP

INCMP

INCMP

CMPLT

OK: Self-diagnosis is carried out and the result is OK.

NG: Self-diagnosis is carried out and the result is NG.
: Self-diagnosis is not carried out.

Revision: 2007 June

EC-110

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
When all SRT related self-diagnoses showed OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will
indicate CMPLT. Case 1 above
A
When all SRT related self-diagnoses showed OK results through several different cycles, the SRT will indicate
CMPLT at the time the respective self-diagnoses have at least one OK result. Case 2 above
If one or more SRT related self-diagnoses showed NG results in 2 consecutive cycles, the SRT will also indiEC
cate CMPLT. Case 3 above
The table above shows that the minimum number of cycles for setting SRT as INCMP is one (1) for each
self-diagnosis (Case 1 & 2) or two (2) for one of self-diagnoses (Case 3). However, in preparation for the state
emissions inspection, it is unnecessary for each self-diagnosis to be executed twice (Case 3) for the following C
reasons:
The SRT will indicate CMPLT at the time the respective self-diagnoses have one (1) OK result.
The emissions inspection requires CMPLT of the SRT only with OK self-diagnosis results.
D
When, during SRT driving pattern, 1st trip DTC (NG) is detected prior to CMPLT of SRT, the self-diagnosis
memory must be erased from ECM after repair.
If the 1st trip DTC is erased, all the SRT will indicate INCMP.
E
NOTE:
SRT can be set as CMPLT together with the DTC(s). Therefore, DTC check must always be carried out
prior to the state emission inspection even though the SRT indicates CMPLT.
SRT Service Procedure
If a vehicle has failed the state emissions inspection due to one or more SRT items indicating INCMP, review
the flowchart diagnostic sequence on the next page.

Revision: 2007 June

EC-111

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

PBIB2320E

*1

How to Read DTC and 1st Trip DTC *2

How to Display SRT Status

*3

How to Set SRT Code

How to Display SRT Status

WITH CONSULT-III
Selecting SRT STATUS in DTC CONFIRMATION mode with CONSULT-III.
For items whose SRT codes are set, a CMPLT is displayed on the CONSULT-III screen; for items whose
SRT codes are not set, INCMP is displayed.
NOTE:
Though displayed on the CONSULT-III screen, HO2S HTR is not SRT item.
WITH GST
Selecting Service $01 with GST (Generic Scan Tool)
NO TOOLS
A SRT code itself can not be displayed while only SRT status can be.
1. Turn ignition switch ON and wait 20 seconds.
2. SRT status is indicated as shown below.
When all SRT codes are set, MIL lights up continuously.

Revision: 2007 June

EC-112

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

< FUNCTION DIAGNOSIS >
When any SRT codes are not set, MIL will flash periodically for 10 seconds.

[VQ37VHR]
A

EC

PBIB2317E

MALFUNCTION INDICATOR LAMP (MIL)

Description
The MIL is located on the combination meter.
1. The MIL will light up when the ignition switch is turned ON without the engine running. This is a bulb check.
If the MIL does not light up, refer to EC-503, "Component Function Check".
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.

J
SEF217U

On Board Diagnostic System Function

The on board diagnostic system has the following three functions.

Revision: 2007 June

EC-113

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Diagnostic Test
Mode

KEY and ENG.

Status

Function

Explanation of Function

Mode I

Ignition switch in
ON position

BULB CHECK

This function checks the MIL bulb for damage (blown, open
circuit, etc.).
If the MIL does not come on, check MIL circuit.

Engine running

MALFUNCTION
WARNING

This is a usual driving condition. When a malfunction is detected twice in two consecutive driving cycles (two trip detection logic), the MIL will light up to inform the driver that a
malfunction has been detected.
The following malfunctions will light up or blink the MIL in
the 1st trip.
Misfire (Possible three way catalyst damage)
One trip detection diagnoses

Ignition switch in
ON position

SELF-DIAGNOSTIC
RESULTS

This function allows DTCs and 1st trip DTCs to be read.

Engine stopped

Mode II

Engine stopped

Diagnostic Test Mode I Bulb Check

In this mode, the MIL on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to EC503, "Component Function Check".
Diagnostic Test Mode I Malfunction Warning
MIL

Condition

ON

When the malfunction is detected.

OFF

No malfunction.

This DTC number is clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)

Diagnostic Test Mode II Self-diagnostic Results

In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MIL as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MIL does not illuminate in diagnostic test
mode I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MIL
illuminates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are
displayed, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These uniden-

Revision: 2007 June

EC-114

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
tified codes can be identified by using the CONSULT-III or GST. A DTC will be used as an example for how to
read a code.

EC

I
PBIB3005E

A particular trouble code can be identified by the number of four-digit numeral flashes as follows.

Number

Flashes

10

11

12

13

14

15

16

The length of time the 1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-second) - OFF (0.6-second) cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-second ON and 0.3-second OFF cycle.
A change from one digit numeral to another occurs at an interval of 1.0-second OFF. In other words, the later
numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occurs at an interval of 1.8-second OFF.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC 0000 refers to no malfunction. (See EC-552, "DTC Index")
How to Switch Diagnostic Test Mode
NOTE:
It is better to count the time accurately with a clock.
It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
Always ECM returns to Diagnostic Test Mode I after ignition switch is turned OFF.
HOW TO SET DIAGNOSTIC TEST MODE II (SELF-DIAGNOSTIC RESULTS)
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
Fully depress the accelerator pedal.
Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts
blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MIL may start blinking on the halfway of this
10 seconds. This blinking is displaying SRT status and is continued for another 10 seconds.

Revision: 2007 June

EC-115

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

< FUNCTION DIAGNOSIS >
4. Fully release the accelerator pedal.
ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).
NOTE:
Wait until the same DTC (or 1st trip DTC) appears to confirm all DTCs certainly.

[VQ37VHR]

PBIB0092E

HOW TO ERASE DIAGNOSTIC TEST MODE II (SELF-DIAGNOSTIC RESULTS)

1. Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to How to Set Diagnostic Test Mode II
(Self-diagnostic Results).
2. Fully depress the accelerator pedal and keep it for more than 10 seconds.
The emission-related diagnostic information has been erased from the backup memory in the ECM.
3. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
The DTC can be erased from the back up memory in the ECM by depressing accelerator pedal. Refer to How
to Erase Diagnostic Test Mode II (Self-diagnostic Results).
If the battery is disconnected, the DTC will be lost from the backup memory within 24 hours.
Be careful not to erase the stored memory before starting trouble diagnoses.

OBD System Operation Chart

Relationship Between MIL, 1st Trip DTC, DTC, and Detectable Items
When a malfunction is detected for the first time, the 1st trip DTC and the 1st trip freeze frame data are
stored in the ECM memory.
When the same malfunction is detected in two consecutive trips, the DTC and the freeze frame data are
stored in the ECM memory, and the MIL will come on.
The MIL will go off after the vehicle is driven 3 times (driving pattern B) with no malfunction. The drive is
counted only when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs
while counting, the counter will reset.
The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) without the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injection System, the DTC and freeze frame data will be stored until the vehicle is driven 80 times (driving pattern
C) without the same malfunction recurring. The TIME in SELF-DIAGNOSTIC RESULTS mode of CONSULT-III will count the number of times the vehicle is driven.
The 1st trip DTC is not displayed when the self-diagnosis results in OK for the 2nd trip.
Summary Chart
Items

Fuel Injection System

Misfire

Other

MIL (goes off)

3 (pattern B)

3 (pattern B)

3 (pattern B)

DTC, Freeze Frame Data (no

display)

80 (pattern C)

80 (pattern C)

40 (pattern A)

1 (pattern C), *1

1 (pattern C), *1

1 (pattern B)

*1, *2

*1, *2

1 (pattern B)

1st Trip DTC (clear)

1st Trip Freeze Frame Data
(clear)

For details about patterns B and C under Fuel Injection System and Misfire, see EXPLANATION FOR DRIVING PATTERNS FOR
MISFIRE <EXHAUST QUALITY DETERIORATION>, FUEL INJECTION SYSTEM.
For details about patterns A and B under Other, see EXPLANATION FOR DRIVING PATTERNS FOR MISFIRE <EXHAUST QUALITY
DETERIORATION>, FUEL INJECTION SYSTEM.
*1: Clear timing is at the moment OK is detected.
*2: Clear timing is when the same malfunction is detected in the 2nd trip.

Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns for Misfire <Exhaust Quality Deterioration>,

Revision: 2007 June

EC-116

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Fuel Injection System

EC

SEF392S

M
*1: When the same malfunction is detected in two consecutive trips, MIL
will light up.

*2: MIL will go off after vehicle is driven 3 *3: When the same malfunction is detected in two consecutive trips, the
times (pattern B) without any malDTC and the freeze frame data will be
functions.
stored in ECM.

*6: The 1st trip DTC and the 1st trip

*4: The DTC and the freeze frame data *5: When a malfunction is detected for
freeze frame data will be cleared at
the first time, the 1st trip DTC and the
will not be displayed any longer after
the moment OK is detected.
1st trip freeze frame data will be
vehicle is driven 80 times (pattern C)
stored in ECM.
without the same malfunction. (The
DTC and the freeze frame data still
remain in ECM.)
*7: When the same malfunction is detected in the 2nd trip, the 1st trip
freeze frame data will be cleared.

EC-117

*8: 1st trip DTC will be cleared when vehicle is driven once (pattern C) without the same malfunction after DTC
is stored in ECM.

Explanation for Driving Patterns for Misfire <Exhaust Quality Deterioration>, Fuel Injection System
<Driving Pattern B>
Driving pattern B means the vehicle operation as follows:

Revision: 2007 June

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]
< FUNCTION DIAGNOSIS >
All components and systems should be monitored at least once by the OBD system.
The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
The B counter will be counted up when driving pattern B is satisfied without any malfunction.
The MIL will go off when the B counter reaches 3. (*2 in OBD SYSTEM OPERATION CHART)
<Driving Pattern C>
Driving pattern C means the vehicle operation as follows:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data) 375 rpm
Calculated load value: (Calculated load value in the freeze frame data) x (10.1) [%]
Engine coolant temperature (T) condition:
When the freeze frame data shows lower than 70C (158F), T should be lower than 70C (158F).
When the freeze frame data shows higher than or equal to 70C (158F), T should be higher than or equal to
70C (158F).
Example:
If the stored freeze frame data is as follows:
Engine speed: 850 rpm, Calculated load value: 30%, Engine coolant temperature: 80C (176F)
To be satisfied with driving pattern C, the vehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70C
(158F)
The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.
The C counter will be counted up when vehicle conditions above is satisfied without the same malfunction.
The DTC will not be displayed after C counter reaches 80.
The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is
stored in ECM.
Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns Except For Misfire <Exhaust Quality Deterioration>, Fuel Injection System

Revision: 2007 June

EC-118

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

EC

L
SEF393SD

*1: When the same malfunction is detected in two consecutive trips, MIL
will light up.

*2: MIL will go off after vehicle is driven 3 *3: When the same malfunction is detected in two consecutive trips, the
times (pattern B) without any malDTC and the freeze frame data will be
functions.
stored in ECM.

*4: The DTC and the freeze frame data

will not be displayed any longer after
vehicle is driven 40 times (pattern A)
without the same malfunction.
(The DTC and the freeze frame data
still remain in ECM.)

*6: 1st trip DTC will be cleared after vehi*5: When a malfunction is detected for
cle is driven once (pattern B) without
the first time, the 1st trip DTC and the
the same malfunction.
1st trip freeze frame data will be
stored in ECM.

*7: When the same malfunction is detected in the 2nd trip, the 1st trip
freeze frame data will be cleared.

Explanation for Driving Patterns Except for Misfire <Exhaust Quality Deterioration>, Fuel Injection System

Revision: 2007 June

EC-119

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

<Driving Pattern A>

AEC574

The A counter will be cleared when the malfunction is detected regardless of (1) - (4).
The A counter will be counted up when (1) - (4) are satisfied without the same malfunction.
The DTC will not be displayed after the A counter reaches 40.
<Driving Pattern B>
Driving pattern B means the vehicle operation as follows:
All components and systems should be monitored at least once by the OBD system.
The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
The B counter will be counted up when driving pattern B is satisfied without any malfunctions.
The MIL will go off when the B counter reaches 3 (*2 in OBD SYSTEM OPERATION CHART).

CONSULT-III Function

INFOID:0000000001733965

FUNCTION
Diagnostic test mode

Function

Work support

This mode enables a technician to adjust some devices faster and more accurately by following the indications on the CONSULT-III unit.

Self-diagnostic results

Self-diagnostic results such as 1st trip DTC, DTCs and 1st trip freeze frame data or freeze frame data
can be read and erased quickly.*

Data monitor

Input/Output data in the ECM can be read.

CAN diagnostic support monThe results of transmit/receive diagnosis of CAN communication can be read.
itor
Active test

Diagnostic Test Mode in which CONSULT-III drives some actuators apart from the ECMs and also shifts
some parameters in a specified range.

DTC & SRT confirmation

The status of system monitoring tests and the self-diagnosis status/result can be confirmed.

Function test

This mode is used to inform customers when their vehicle condition requires periodic maintenance.

ECU part number

ECM part number can be read.

*: The following emission-related diagnostic information is cleared when the ECM memory is erased.
Diagnostic trouble codes
1st trip diagnostic trouble codes
Freeze frame data
1st trip freeze frame data
System readiness test (SRT) codes
Test values

ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION

Revision: 2007 June

EC-120

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

DIAGNOSTIC TEST MODE
SELF-DIAGNOSTIC
RESULTS

INPUT

ENGINE CONTROL COMPONENT PARTS

Item

WORK
SUPPORT

DATA
MONITOR

A
DTC & SRT
CONFIRMATION

ACTIVE
TEST

DTC
WORK
SUPPORT

DTC*1

FREEZE
FRAME
DATA*2

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)

Mass air flow sensor

Engine coolant temperature sensor

Engine oil temperature sensor

Air fuel ratio (A/F) sensor 1

Heated oxygen sensor 2

Wheel sensor

Accelerator pedal position sensor

Throttle position sensor

Fuel tank temperature sensor

EVAP control system pressure sensor

Intake air temperature sensor

Knock sensor

SRT STATUS

EC

Refrigerant pressure sensor

Closed throttle position switch (accelerator pedal position sensor signal)

Air conditioner switch

Park/neutral position (PNP) switch

Stop lamp switch

Power steering pressure sensor

Battery voltage

Load signal

Fuel level sensor

Battery current sensor

ICC steering switch

ASCD steering switch

ICC brake switch

ASCD brake switch

VVEL control shaft position sensor

Manifold absolute pressure (MAP)

sensor

Brake booster pressure sensor

Revision: 2007 June

EC-121

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

DIAGNOSTIC TEST MODE
SELF-DIAGNOSTIC
RESULTS

DATA
MONITOR

ACTIVE
TEST

Fuel injector

Power transistor (Ignition timing)

Item

WORK
SUPPORT

DTC*1

Throttle control motor relay

Throttle control motor

EVAP canister purge volume control

solenoid valve

FREEZE
FRAME
DATA*2

Fuel pump relay

SRT STATUS

Cooling fan relay

Air fuel ratio (A/F) sensor 1 heater

*3

Heated oxygen sensor 2 heater

*3

Intake valve timing control solenoid

valve

VVEL actuator motor relay

EVAP canister vent control valve

VVEL actuator motor

DTC
WORK
SUPPORT

Air conditioner relay

OUTPUT

ENGINE CONTROL COMPONENT PARTS

DTC & SRT

CONFIRMATION

Alternator

Calculated load value

: Applicable
*1: This item includes 1st trip DTCs.
*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-III screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-107, "Diagnosis Description".
*3: Always CMPLT is displayed.

WORK SUPPORT MODE

Work Item

Revision: 2007 June

EC-122

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

WORK ITEM

CONDITION

USAGE

IDLE AIR VOL LEARN

THE IDLE AIR VOLUME THAT KEEPS THE ENGINE

WITHIN THE SPECIFIED RANGE IS MEMORIZED IN
ECM.

EVAP SYSTEM CLOSE

CLOSE THE EVAP CANISTER VENT CONTROL VALVE IN

ORDER TO MAKE EVAP SYSTEM CLOSE UNDER THE
FOLLOWING CONDITIONS.
IGN SW ON
ENGINE NOT RUNNING
AMBIENT TEMPERATURE IS ABOVE 0C (32F).
NO VACUUM AND NO HIGH PRESSURE IN EVAP SYSTEM
FUEL TANK TEMP. IS MORE THAN 0C (32F).
WITHIN 10 MINUTES AFTER STARTING EVAP SYSTEM CLOSE
WHEN TRYING TO EXECUTE EVAP SYSTEM CLOSE
UNDER THE CONDITION EXCEPT ABOVE, CONSULTIII WILL DISCONTINUE IT AND DISPLAY APPROPRIATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-III MAY DISPLAY BATTERY VOLTAGE IS LOW. CHARGE BATTERY, EVEN IN USING CHARGED BATTERY.

When detecting EVAP vapor leak

point of EVAP system

FUEL PRESSURE RELEASE

FUEL PUMP WILL STOP BY TOUCHING START DURING IDLING.

CRANK A FEW TIMES AFTER ENGINE STALLS.

When releasing fuel pressure from

fuel line

SELF-LEARNING CONT

THE COEFFICIENT OF SELF-LEARNING CONTROL

MIXTURE RATIO RETURNS TO THE ORIGINAL COEFFICIENT.

When clearing mixture ratio selflearning value

TARGET IDLE RPM ADJ*

IDLE CONDITION

When setting target idle speed

TARGET IGN TIM ADJ*

IDLE CONDITION

When adjusting target ignition timing

VIN REGISTRATION

IN THIS MODE, VIN IS REGISTERED IN ECM.

When registering VIN in ECM

VVEL POS SEN ADJ PREP

USE THIS ITEM ONLY WHEN REPLACING VVEL ACTUATOR SUB ASSEMBLY.
IGNITION ON AND ENGINE STOPPED.

When adjusting VVEL control

shaft position sensor

When learning the idle air volume

EC

*: This function is not necessary in the usual service procedure.

SELF-DIAG RESULTS MODE

Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-552, "DTC Index".)

Freeze Frame Data and 1st Trip Freeze Frame Data

Freeze frame data
item*

Description

DIAG TROUBLE
CODE
[PXXXX]

The engine control component part/control system has a trouble code, it is displayed as PXXXX. (Refer to
EC-552, "DTC Index".)

CAL/LD VALUE [%]

The calculated load value at the moment a malfunction is detected is displayed.

COOLANT TEMP [C]

or [F]

The engine coolant temperature at the moment a malfunction is detected is displayed.

L-FUEL TRM-B1 [%]

L-FUEL TRM-B2 [%]
S-FUEL TRM-B1 [%]
S-FUEL TRM-B2 [%]

Revision: 2007 June

Long-term fuel trim at the moment a malfunction is detected is displayed.

The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule than
short-term fuel trim.
Short-term fuel trim at the moment a malfunction is detected is displayed.
The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel schedule.

EC-123

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Freeze frame data
item*

Description

ENGINE SPEED [rpm]

The engine speed at the moment a malfunction is detected is displayed

VEHICL SPEED
[km/h] or [mph]

The vehicle speed at the moment a malfunction is detected is displayed

ABSOL THP/S [%]

The throttle valve opening angle at the moment a malfunction is detected is displayed

B/FUEL SCHDL
[msec]

The base fuel schedule at the moment a malfunction is detected is displayed

INT/A TEMP SE [C]

or [F]

The intake air temperature at the moment a malfunction is detected is displayed

FUEL SYS-B1

FUEL SYS-B2

Fuel injection system status at the moment a malfunction is detected is displayed.

One mode in the following is displayed.
Mode2: Open loop due to detected system malfunction
Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
Mode5: Open loop - has not yet satisfied condition to go to closed loop

*: The items are the same as those of 1st trip freeze frame data.

DATA MONITOR MODE

Monitored Item
: Applicable

Monitored item

ENG SPEED

Unit

Description
Indicates the engine speed computed from the
signal of the crankshaft position sensor (POS)
and camshaft position sensor (PHASE).

Accuracy becomes poor if engine

speed drops below the idle rpm.
If the signal is interrupted while the
engine is running, an abnormal value
may be indicated.

The signal voltage of the mass air flow sensor is

displayed.

When the engine is stopped, a certain

value is indicated.
When engine is running specification
range is indicated in SPEC.

msec

Base fuel schedule indicates the fuel injection

pulse width programmed into ECM, prior to any
learned on board correction.

When engine is running specification

range is indicated in SPEC.

The mean value of the air-fuel ratio feedback correction factor per cycle is indicated.

When the engine is stopped, a certain

value is indicated.
This data also includes the data for
the air-fuel ratio learning control.
When engine is running specification
range is indicated in SPEC.

C or F

The engine coolant temperature (determined by

the signal voltage of the engine coolant temperature sensor) is displayed.

When the engine coolant temperature

sensor is open or short-circuited,
ECM enters fail-safe mode. The engine coolant temperature determined
by the ECM is displayed.

The A/F signal computed from the input signal of

the air fuel ratio (A/F) sensor 1 is displayed.

The signal voltage of the heated oxygen sensor 2

is displayed.

RICH/LEAN

Display of heated oxygen sensor 2 signal:

RICH: means the amount of oxygen after three
way catalyst is relatively small.
LEAN: means the amount of oxygen after three
way catalyst is relatively large.

km/h or mph

The vehicle speed computed from the vehicle

speed signal sent from combination meter is displayed.

rpm

MAS A/F SE-B1

MAS A/F SE-B2

B/FUEL SCHDL
A/F ALPHA-B1

A/F ALPHA-B2

COOLAN TEMP/S

A/F SEN1 (B1)

A/F SEN1 (B2)
HO2S2 (B1)
HO2S2 (B2)
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)

VHCL SPEED SE

Revision: 2007 June

Remarks

E C -1 2 4

When the engine is stopped, a certain

value is indicated.

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Monitored item
BATTERY VOLT

Unit

The accelerator pedal position sensor signal voltage is displayed.

ACCEL SEN 2 signal is converted by

ECM internally. Thus, they differs
from ECM terminal voltage signal.

EC

The throttle position sensor signal voltage is displayed.

TP SEN 2-B1 signal is converted by

ECM internally. Thus, they differs
from ECM terminal voltage signal.

C or F

The fuel temperature (determined by the signal

voltage of the fuel tank temperature sensor) is
displayed.

C or F

The intake air temperature (determined by the

signal voltage of the intake air temperature sensor) is indicated.

EVAP SYS PRES

The signal voltage of EVAP control system pressure sensor is displayed.

FUEL LEVEL SE

The signal voltage of the fuel level sensor is displayed.

START SIGNAL

ON/OFF

Indicates start signal status [ON/OFF] computed

by the ECM according to the signals of engine
speed and battery voltage.

FUEL T/TMP SE

INT/A TEMP SE

ON/OFF

Indicates idle position [ON/OFF] computed by

ECM according to the accelerator pedal position
sensor signal.

ON/OFF

Indicates [ON/OFF] condition of the air conditioner switch as determined by the air conditioner signal.

P/N POSI SW

ON/OFF

Indicates [ON/OFF] condition from the park/neutral position (PNP) switch signal.

PW/ST SIGNAL

ON/OFF

[ON/OFF] condition of the power steering system

(determined by the signal voltage of the power
steering pressure sensor signal) is indicated.

ON/OFF

Indicates [ON/OFF] condition from the electrical

load signal.
ON: Rear window defogger switch is ON and/or
lighting switch is in 2nd position.
OFF: Both rear window defogger switch and lighting switch are OFF.

CLSD THL POS

AIR COND SIG

LOAD SIGNAL

The power supply voltage of ECM is displayed.

TP SEN 1-B1
TP SEN 2-B1

Remarks

ACCEL SEN 1
ACCEL SEN 2

Description

F
After starting the engine, [OFF] is displayed regardless of the starter signal.

IGNITION SW

ON/OFF

Indicates [ON/OFF] condition from ignition switch

signal.

HEATER FAN SW

ON/OFF

Indicates [ON/OFF] condition from the heater fan

switch signal.

BOOST VCUM SW

ON/OFF

Always a certain value is displayed.

This item is not efficient for CV36 models.

BRAKE SW

ON/OFF

Indicates [ON/OFF] condition from the stop lamp

switch signal.

msec

Indicates the actual fuel injection pulse width

compensated by ECM according to the input signals.

When the engine is stopped, a certain

computed value is indicated.

BTDC

Indicates the ignition timing computed by ECM

according to the input signals.

When the engine is stopped, a certain

value is indicated.

INJ PULSE-B1
INJ PULSE-B2
IGN TIMING
CAL/LD VALUE

MASS AIRFLOW

Revision: 2007 June

Calculated load value indicates the value of the

current air flow divided by peak air flow.

gm/s

Indicates the mass air flow computed by ECM according to the signal voltage of the mass air flow
sensor.

EC-125

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Monitored item

Unit

Description

Indicates the EVAP canister purge volume control solenoid valve control value computed by the
ECM according to the input signals.
The opening becomes larger as the value increases.

The control value of the intake valve timing control solenoid valve (determined by ECM according to the input signals) is indicated.
The advance angle becomes larger as the value
increases.

The throttle position sensor signal voltage is displayed.

AIR COND RLY

ON/OFF

The air conditioner relay control condition (determined by ECM according to the input signals) is
indicated.

FUEL PUMP RLY

ON/OFF

Indicates the fuel pump relay control condition

determined by ECM according to the input signals.

VENT CONT/V

ON/OFF

The control condition of the EVAP canister vent

control valve (determined by ECM according to
the input signals) is indicated.
ON: Closed
OFF: Open

THRTL RELAY

ON/OFF

Indicates the throttle control motor relay control

condition determined by the ECM according to
the input signals.

ON/OFF

Indicates [ON/OFF] condition of heated oxygen

sensor 2 heater determined by ECM according to
the input signals.

PURG VOL C/V

INT/V SOL (B1)

INT/V SOL (B2)
TP SEN 1-B2
TP SEN 2-B2

HO2S2 HTR (B1)

HO2S2 HTR (B2)

rpm

Indicates the engine speed computed from the

turbine revolution sensor signal.

km/h or mph

The vehicle speed computed from the vehicle

speed signal sent from TCM is displayed.

IDL A/V LEARN

YET/CMPLT

Display the condition of Idle Air Volume Learning

YET: Idle air volume learning has not been performed yet.
CMPLT: Idle air volume learning has already
been performed successfully.

ENG OIL TEMP

C or F

The engine oil temperature (determined by the

signal voltage of the engine oil temperature sensor) is displayed.

I/P PULLY SPD

VEHICLE SPEED

TRVL AFTER MIL

km or mile

A/F S1 HTR (B1)

%

AC PRESS SEN

The signal voltage from the refrigerant pressure

sensor is displayed.

VHCL SPEED SE

km/h or mph

The vehicle speed computed from the vehicle

speed signal sent from combination meter is displayed.

SET VHCL SPD

km/h or mph

The preset vehicle speed is displayed.

MAIN SW

ON/OFF

Indicates [ON/OFF] condition from MAIN switch

signal.

CANCEL SW

ON/OFF

Indicates [ON/OFF] condition from CANCEL

switch signal.

Revision: 2007 June

TP SEN 2-B2 signal is converted by

ECM internally. Thus, they differs
from ECM terminal voltage signal.

Distance traveled while MIL is activated.

Air fuel ratio (A/F) sensor 1 heater control value
computed by ECM according to the input signals.
The current flow to the heater becomes larger as
the value increases.

A/F S1 HTR (B2)

Remarks

EC-126

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Monitored item

Unit

Description

RESUME/ACC SW

ON/OFF

Indicates [ON/OFF] condition from RESUME/ACCELERATE switch signal.

SET SW

ON/OFF

Indicates [ON/OFF] condition from SET/COAST

switch signal.

BRAKE SW1

ON/OFF

Indicates [ON/OFF] condition from ASCD brake

switch signal.

BRAKE SW2

ON/OFF

Indicates [ON/OFF] condition of stop lamp switch

signal.

DIST SW

ON/OFF

Indicates [ON/OFF] condition from DISTANCE

switch signal.

NON/CUT

Indicates the vehicle cruise condition.

NON: Vehicle speed is maintained at the ASCD
set speed.
CUT: Vehicle speed decreased to excessively
low compared with the ASCD set speed, and
ASCD operation is cut off.

NON/CUT

Indicates the vehicle cruise condition.

NON: Vehicle speed is maintained at the ASCD
set speed.
CUT: Vehicle speed decreased to excessively
low, and ASCD operation is cut off.

VHCL SPD CUT

LO SPEED CUT

Remarks

EC

ON/OFF

Indicates [ON/OFF] condition of A/T O/D according to the input signal from the TCM.

For M/T models, always OFF is displayed.

AT OD CANCEL

ON/OFF

Indicates [ON/OFF] condition of A/T O/D cancel

request signal.

For M/T models, always OFF is displayed.

CRUISE LAMP

ON/OFF

Indicates [ON/OFF] condition of CRUISE lamp

determined by the ECM according to the input
signals.

SET LAMP

ON/OFF

Indicates [ON/OFF] condition of SET lamp determined by the ECM according to the input signals.

AT OD MONITOR

BAT CUR SEN

ALT DUTY SIG

mV

A/F ADJ-B2

ON/OFF

Indicates the correction of factor stored in ECM.

The factor is calculated from the difference between the target air-fuel ratio stored in ECM and
the air-fuel ratio calculated from A/F sensor 1 signal.

Indicates a command value for cooling fan. The

value is calculated by ECM based on input signals.

AC EVA TEMP

C or F

Indicates A/C evaporator temperature sent from

unified meter and A/C amp..

AC EVA TARGET

C or F

Indicates target A/C evaporator temperature sent

from unified meter and A/C amp..

Indicates the duty ratio of the power generation

command value. The ratio is calculated by ECM
based on the battery current sensor signal.

FAN DUTY

ALTDUTY

Revision: 2007 June

The signal voltage of battery current sensor is

displayed.
The control condition of the power generation
voltage variable control (determined by ECM according to the input signals) is indicated.
ON: Power generation voltage variable control is
active.
OFF: Power generation voltage variable control
is inactive.

A/F ADJ-B1

EC-127

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

Monitored item

Unit

VVEL SEN LEARNB1

VVEL SEN LEARNB2
VVEL POSITION
SEN-B1
VVEL POSITION
SEN-B2
VVEL TIM-B1

Indicates the VVEL learning value.

The VVEL control shaft position sensor signal

voltage is displayed.

deg

VVEL TIM-B2

VVEL LEARN

Description

YET/DONE

Remarks

Indicates [deg] of VVEL control shaft angle.

Display the condition of VVEL learning
YET: VVEL learning has not been performed yet.
CMPLT: VVEL learning has already been performed successfully.

NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.

ACTIVE TEST MODE

Test Item
TEST ITEM

CONDITION

JUDGEMENT

VENT CONTROL/V

Ignition switch: ON (Engine

stopped)
Turn solenoid valve ON and OFF
with the CONSULT-III and listen
to operating sound.

Solenoid valve makes an operating

sound.

Harness and connectors

Solenoid valve

ENG COOLANT
TEMP

Engine: Return to the original

trouble condition
Change the engine coolant temperature using CONSULT-III.

If trouble symptom disappears, see

CHECK ITEM.

Harness and connectors

Engine coolant temperature sensor
Fuel injector

FUEL INJECTION

Engine: Return to the original

trouble condition
Change the amount of fuel injection using CONSULT-III.

If trouble symptom disappears, see

CHECK ITEM.

Harness and connectors

Fuel injector
Air fuel ratio (A/F) sensor 1

FUEL/T TEMP
SEN

Change the fuel tank temperature using CONSULT-III.

PURG VOL
CONT/V

Engine: After warming up, run engine at 1,500 rpm.

Change the EVAP canister purge
volume control solenoid valve
opening percent using CONSULT-III.

Engine speed changes according to

the opening percent.

Harness and connectors

Solenoid valve

FUEL PUMP RELAY

Ignition switch: ON (Engine

stopped)
Turn the fuel pump relay ON and
OFF using CONSULT-III and listen to operating sound.

Fuel pump relay makes the operating sound.

Harness and connectors

Fuel pump relay

IGNITION TIMING

Engine: Return to the original

trouble condition
Timing light: Set
Retard the ignition timing using
CONSULT-III.

If trouble symptom disappears, see

CHECK ITEM.

Perform Idle Air Volume Learning.

FAN DUTY CONTROL*

Ignition switch: ON
Change duty ratio using CONSULT-III.

Cooling fan speed changes.

Revision: 2007 June

EC-128

CHECK ITEM (REMEDY)

Harness and connectors

Cooling fan motor
Cooling fan relay
Cooling fan control module
IPDM E/R

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

TEST ITEM

CONDITION

JUDGEMENT

ALTERNATOR
DUTY

Engine: Idle
Change duty ratio using CONSULT-III.

POWER BALANCE

Engine: After warming up, idle the

engine.
A/C switch OFF
Selector lever: P or N (A/T), Neutral (M/T)
Cut off each injector signal one at
a time using CONSULT-III.

CHECK ITEM (REMEDY)

Battery voltage changes.

Harness and connectors

IPDM E/R
Alternator

Engine runs rough or dies.

EC

Harness and connectors

Compression
Fuel injector
Power transistor
Spark plug
Ignition coil

*: Leaving cooling fan OFF with CONSULT-III while engine is running may cause the engine to overheat.

DTC & SRT CONFIRMATION MODE

SRT STATUS Mode
For details, refer to EC-107, "Diagnosis Description".

SRT WORK SUPPORT Mode

This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.

DTC WORK SUPPORT Mode

Test mode

Test item

Corresponding DTC No.

Reference page

P0442

EC-282

P0455

EC-318

P0456

EC-324

PURG VOL CN/V P1444

P0443

EC-288

PURG FLOW P0441

P0441

EC-277

A/F SEN1 (B1) P1278/P1279

P0133

EC-207

A/F SEN1 (B1) P1276

P0130

EC-197

A/F SEN1 (B2) P1288/P1289

P0153

EC-207

A/F SEN1 (B2) P1286

P0150

EC-197

HO2S2 (B1) P1146

P0138

EC-218

HO2S2 (B1) P1147

P0137

EC-212

HO2S2 (B1) P0139

P0139

EC-226

HO2S2 (B2) P1166

P0158

EC-218

HO2S2 (B2) P1167

P0157

EC-212

HO2S2 (B2) P0159

P0159

EC-226

EVP SML LEAK P0442/P1442*

EVAPORATIVE SYSTEM

A/F SEN1

HO2S2

EVP V/S LEAK P0456/P1456*

*: DTC P1442 and P1456 does not apply to CV36 models but appears in DTC Work Support Mode screens.

Diagnosis Tool Function

INFOID:0000000001733966

DESCRIPTION
Generic Scan Tool (OBDII scan tool) complying with SAE J1978 has
8 different functions explained below.
ISO15765-4 is used as the protocol.
The name GST or Generic Scan Tool is used in this service manual.

SEF139P

Revision: 2007 June

EC-129

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

[VQ37VHR]

< FUNCTION DIAGNOSIS >

FUNCTION
Diagnostic Service

Function

Service $01

READINESS TESTS

This diagnostic service gains access to current emission-related data values, including analog inputs and outputs, digital inputs and outputs, and system status information.

Service $02

(FREEZE DATA)

This diagnostic service gains access to emission-related data value which were stored by
ECM during the freeze frame. For details, refer to EC-552, "DTC Index".

Service $03

DTCs

This diagnostic service gains access to emission-related power train trouble codes which
were stored by ECM.

Service $04

CLEAR DIAG INFO

This diagnostic service can clear all emission-related diagnostic information. This includes:
Clear number of diagnostic trouble codes (Service $01)
Clear diagnostic trouble codes (Service $03)
Clear trouble code for freeze frame data (Service $01)
Clear freeze frame data (Service $02)
Reset status of system monitoring test (Service $01)
Clear on board monitoring test results (Service $06 and $07)

Service $06

(ON BOARD TESTS)

This diagnostic service accesses the results of on board diagnostic monitoring tests of
specific components/systems that are not continuously monitored.

Service $07

(ON BOARD TESTS)

This diagnostic service enables the off board test drive to obtain test results for emissionrelated powertrain components/systems that are continuously monitored during normal
driving conditions.

Service $08

Service $09

(CALIBRATION ID)

This diagnostic service can close EVAP system in ignition switch ON position (Engine
stopped). When this diagnostic service is performed, EVAP canister vent control valve can
be closed.
In the following conditions, this diagnostic service cannot function.
Low ambient temperature
Low battery voltage
Engine running
Ignition switch OFF
Low fuel temperature
Too much pressure is applied to EVAP system
This diagnostic service enables the off-board test device to request specific vehicle information such as Vehicle Identification Number (VIN) and Calibration IDs.

INSPECTION PROCEDURE
1.
2.

Turn ignition switch OFF.

Connect GST to data link connector (1), which is located under
LH dash panel near the hood opener handle.

JMBIA0055ZZ

Revision: 2007 June

EC-130

G37 Coupe

ON BOARD DIAGNOSTIC (OBD) SYSTEM

< FUNCTION DIAGNOSIS >
3. Turn ignition switch ON.
4. Enter the program according to instruction on the screen or in
the operation manual.
(*: Regarding GST screens in this section, sample screens are
shown.)

[VQ37VHR]
A

EC

C
SEF398S

5.

Perform each diagnostic mode according to each service procedure.

For further information, see the GST Operation Manual of
the tool maker.

G
SEF416S

Revision: 2007 June

EC-131

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

COMPONENT DIAGNOSIS
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Description

INFOID:0000000001733967

The specification (SP) value indicates the tolerance of the value that is displayed in SPEC in DATA MONITOR mode of CONSULT-III during normal operation of the Engine Control System. When the value in SPEC
in DATA MONITOR mode is within the SP value, the Engine Control System is confirmed OK. When the
value in SPEC in DATA MONITOR mode is NOT within the SP value, the Engine Control System may have
one or more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:
B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board correction)
A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)
MAS A/F SE-B1/B2 (The signal voltage of the mass air flow sensor)

Component Function Check

INFOID:0000000001733968

1.PRECONDITIONING
Make sure that all of the following conditions are satisfied.
TESTING CONDITION
Vehicle driven distance: More than 5,000 km (3,107 miles)
Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm2, 14.25 - 15.12 psi)
Atmospheric temperature: 20 - 30C (68 - 86F)
Engine coolant temperature: 75 - 95C (167 - 203F)
Transmission: Warmed-up
- For A/T models: After the engine is warmed up to normal operating temperature, drive vehicle until ATF
TEMP SE 1 (A/T fluid temperature sensor signal) indicates more than 60C (140F).
- For M/T models: After the engine is warmed up to normal operating temperature, drive for 5 minutes.
Electrical load: Not applied
- Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Engine speed: Idle
>> GO TO 2.

2.PERFORM SPEC IN DATA MONITOR MODE

With CONSULT-III
NOTE:
Perform SPEC in DATA MONITOR mode in maximum scale display.
1. Perform EC-13, "BASIC INSPECTION : Special Repair Requirement".
2. Select B/FUEL SCHDL, A/F ALPHA-B1, A/F ALPHA-B2, MAS A/F SE-B1 and MAS A/F SE-B2 in
SPEC of DATA MONITOR mode with CONSULT-III.
3. Make sure that monitor items are within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> Go to EC-133, "Diagnosis Procedure".

Revision: 2007 June

EC-132

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001733969

OVERALL SEQUENCE
EC

P
PBIB2268E

Revision: 2007 June

EC-133

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

JMBIA0056GB

DETAILED PROCEDURE

1.CHECK A/F ALPHA-B1, A/F ALPHA-B2

1.
2.
3.

With CONSULT-III
Start engine.
Confirm that the testing conditions are met. Refer to EC-132, "Component Function Check".
Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.

Revision: 2007 June

EC-134

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]
< COMPONENT DIAGNOSIS >
NOTE:
Check A/F ALPHA-B1, A/F ALPHA-B2 for approximately 1 minute because they may fluctuate. It is NG A
if the indication is out of the SP value even a little.
Is the measurement value within the SP value?
YES >> GO TO 17.
EC
NO-1 >> Less than the SP value: GO TO 2.
NO-2 >> More than the SP value: GO TO 3.

2.CHECK B/FUEL SCHDL

Select B/FUEL SCHDL in SPEC of DATA MONITOR mode, and make sure that the indication is within the
SP value.
Is the measurement value within the SP value?
YES >> GO TO 4.
NO
>> More than the SP value: GO TO 19.

3.CHECK B/FUEL SCHDL

Select B/FUEL SCHDL in SPEC of DATA MONITOR mode, and make sure that the indication is within the
SP value.
Is the measurement value within the SP value?
YES >> GO TO 6.
NO-1 >> More than the SP value: GO TO 6.
NO-2 >> Less than the SP value: GO TO 25.

4.CHECK A/F ALPHA-B1, A/F ALPHA-B2

1.
2.
3.
4.

Stop the engine.

Disconnect PCV hose, and then plug it.
Start engine.
Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.
Is the measurement value within the SP value?
YES >> GO TO 5.
NO
>> GO TO 6.

5.CHANGE ENGINE OIL

1.
2.

Stop the engine.

Change engine oil.
NOTE:
This symptom may occur when a large amount of gasoline is mixed with engine oil because of driving
conditions (such as when engine oil temperature does not rise enough since a journey distance is too
short during winter). The symptom will not be detected after changing engine oil or changing driving condition.

>> INSPECTION END

6.CHECK FUEL PRESSURE

Check fuel pressure. (Refer to EC-601, "Inspection".)

Is the inspection result normal?
YES >> GO TO 9.
NO-1 >> Fuel pressure is too high: Replace fuel filter and fuel pump assembly and then GO TO 8.
NO-2 >> Fuel pressure is too low: GO TO 7.

7.DETECT MALFUNCTIONING PART

Check fuel hoses and fuel tubes for clogging.

Is the inspection result normal?
YES >> Replace fuel filter and fuel pump assembly and then GO TO 8.
NO
>> Repair or replace and then GO TO 8.

8.CHECK A/F ALPHA-B1, A/F ALPHA-B2

Revision: 2007 June

EC-135

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Start engine.
2. Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> GO TO 9.

9.PERFORM POWER BALANCE TEST

1. Perform POWER BALANCE in ACTIVE TEST mode.
2. Make sure that the each cylinder produces a momentary engine speed drop.
Is the inspection result normal?
YES >> GO TO 12.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the following.
Ignition coil and its circuit (Refer to EC-498, "Component Function Check".)
Fuel injector and its circuit (Refer to EC-487, "Component Function Check".)
Intake air leakage
Low compression pressure (Refer to EM-22, "Inspection".)
Is the inspection result normal?
YES >> Replace fuel injector and then GO TO 11.
NO
>> Repair or replace malfunctioning part and then GO TO 11.

11.CHECK A/F ALPHA-B1, A/F ALPHA-B2

1.
2.

Start engine.
Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> GO TO 12.

12.CHECK A/F SENSOR 1 FUNCTION

Perform all DTC CONFIRMATION PROCEDURE related with A/F sensor 1.
For DTC P0130, P0150, refer to EC-197, "DTC Logic".
For DTC P0131, P0151, refer to EC-201, "DTC Logic".
For DTC P0132, P0152, refer to EC-204, "DTC Logic".
For DTC P0133, P0153, refer to EC-207, "DTC Logic".
For DTC P2A00, P2A03, refer to EC-471, "DTC Logic".
Is any DTC detected?
YES >> GO TO 13.
NO
>> GO TO 15.

13.CHECK A/F SENSOR 1 CIRCUIT

Perform Diagnosis Procedure according to corresponding DTC.
>> GO TO 14.

14.CHECK A/F ALPHA-B1, A/F ALPHA-B2

1.
2.

Start engine.
Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> GO TO 15.

15.DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR

1.

Stop the engine.

Revision: 2007 June

EC-136

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]
< COMPONENT DIAGNOSIS >
2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
A

>> GO TO 16.

16.CHECK A/F ALPHA-B1, A/F ALPHA-B2

EC

1.
2.

Start engine.
Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> Detect malfunctioning part according to EC-589, "Symptom Table".

17.CHECK B/FUEL SCHDL

Select B/FUEL SCHDL in SPEC of DATA MONITOR mode, and make sure that the indication is within the
SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO-1 >> More than the SP value: GO TO 18.
NO-2 >> Less than the SP value: GO TO 25.

18.DETECT MALFUNCTIONING PART

1.
2.
-

Check for the cause of large engine friction. Refer to the following.
Engine oil level is too high
Engine oil viscosity
Belt tension of power steering, alternator, A/C compressor, etc. is excessive
Noise from engine
Noise from transmission, etc.
Check for the cause of insufficient combustion. Refer to the following.
Valve clearance malfunction
Intake valve timing control function malfunction
Camshaft sprocket installation malfunction, etc.

>> Repair or replace malfunctioning part, and then GO TO 30.

19.CHECK INTAKE SYSTEM

Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system
Is the inspection result normal?
YES >> GO TO 21.
NO
>> Repair or replace malfunctioning part, and then GO TO 20.

20.CHECK A/F ALPHA-B1, A/F ALPHA-B2, AND B/FUEL SCHDL

Select A/F ALPHA-B1, A/F ALPHA-B2, and B/FUEL SCHDL in SPEC of DATA MONITOR mode, and
make sure that the each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> B/FUEL SCHDL is more, A/F ALPHA-B1, A/F ALPHA-B2 are less than the SP value: GO TO
21.

21.DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR

1.
2.

Stop the engine.

Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and
then reconnect it again.
>> GO TO 22.

Revision: 2007 June

EC-137

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

22.CHECK A/F ALPHA-B1, A/F ALPHA-B2

1.
2.

Start engine.
Select A/F ALPHA-B1, A/F ALPHA-B2 in SPEC of DATA MONITOR mode, and make sure that the
each indication is within the SP value.
Is the measurement value within the SP value?
YES >> Detect malfunctioning part of mass air flow sensor circuit and repair it. Refer to EC-173, "Diagnosis Procedure". Then GO TO 29.
NO
>> GO TO 23.

23.CHECK MAS A/F SE-B1, MAS A/F SE-B2

Select MAS A/F SE-B1, MAS A/F SE-B2 in SPEC of DATA MONITOR mode, and make sure that the
indication is within the SP value.
Is the measurement value within the SP value?
YES >> GO TO 24.
NO
>> More than the SP value: Replace malfunctioning mass air flow sensor, and then GO TO 29.

24.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> GO TO 29.

25.CHECK INTAKE SYSTEM

Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system
Is the inspection result normal?
YES >> GO TO 27.
NO
>> Repair or replace malfunctioning part, and then GO TO 26.

26.CHECK B/FUEL SCHDL

Select B/FUEL SCHDL in SPEC of DATA MONITOR mode, and make sure that the indication is within the
SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> Less than the SP value: GO TO 27.

27.CHECK MAS A/F SE-B1, MAS A/F SE-B2

Select MAS A/F SE-B1, MAS A/F SE-B2 in SPEC of DATA MONITOR mode, and make sure that the
indication is within the SP value.
Is the measurement value within the SP value?
YES >> GO TO 28.
NO
>> Less than the SP value: Replace malfunctioning mass air flow sensor, and then GO TO 30.

28.CHECK INTAKE SYSTEM

Check for the cause of air leak after the mass air flow sensor. Refer to the following.
Disconnection, looseness, and cracks in air duct
Looseness of oil filler cap
Disconnection of oil level gauge
Open stuck, breakage, hose disconnection, or cracks of PCV valve
Disconnection or cracks of EVAP purge hose, open stuck of EVAP canister purge volume control solenoid
valve
Malfunctioning seal of rocker cover gasket
Disconnection, looseness, or cracks of hoses, such as vacuum hose, connecting to intake air system parts
Revision: 2007 June

EC-138

G37 Coupe

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Malfunctioning seal of intake air system, etc.

>> GO TO 30.

29.CHECK A/F ALPHA-B1, A/F ALPHA-B2, AND B/FUEL SCHDL

EC

Select A/F ALPHA-B1, A/F ALPHA-B2, and B/FUEL SCHDL in SPEC of DATA MONITOR mode, and
make sure that the each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> Detect malfunctioning part according to EC-589, "Symptom Table".

30.CHECK B/FUEL SCHDL

Select B/FUEL SCHDL in SPEC of DATA MONITOR mode, and then make sure that the indication is
within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO
>> Detect malfunctioning part according to EC-589, "Symptom Table".

Revision: 2007 June

EC-139

G37 Coupe

POWER SUPPLY AND GROUND CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

POWER SUPPLY AND GROUND CIRCUIT

Diagnosis Procedure

INFOID:0000000001733970

1.INSPECTION START
Start engine.
Is engine running?
YES >> GO TO 8.
NO
>> GO TO 2.

2.CHECK ECM POWER SUPPLY CIRCUIT-I

1.
2.

Turn ignition switch OFF and then ON.

Check the voltage between ECM harness connector and ground.
ECM
Connector

Terminal

F102

53

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
IPDM E/R harness connector E7
10A fuse (No. 44)
Harness for open or short between ECM and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK GROUND CONNECTION-I

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair or replace ground connection.

5.CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I

1.
2.

Disconnect ECM harness connector.

Check the continuity between ECM harness connector and ground.
ECM
Connector

Terminal

F101

Ground

Continuity

Ground

Existed

123
M107

124
127
128

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

Revision: 2007 June

EC-140

G37 Coupe

POWER SUPPLY AND GROUND CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

6.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F103, M116
Harness for open or short between ECM and ground

EC

>> Repair open circuit or short to power in harness or connectors.

7.CHECK ECM POWER SUPPLY CIRCUIT-II

1.
2.
3.

Reconnect ECM harness connector.

Turn ignition switch ON.
Check the voltage between IPDM E/R harness connector and ground.
IPDM E/R
Connector

Terminal

E7

53

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> Go to EC-498, "Diagnosis Procedure".
NO
>> GO TO 8.

8.CHECK ECM POWER SUPPLY CIRCUIT-III

1.
2.

Turn ignition switch OFF and wait at least 10 seconds.

Check the voltage between ECM harness connector and ground.
H
ECM

Connector
M107

Terminal
125

Ground

Voltage

Ground

After turning ignition switch OFF, battery voltage will exist for a few seconds, then drop approximately 0V.

Is the inspection result normal?

YES >> GO TO 15.
NO-1 >> Battery voltage does not exist: GO TO 9.
NO-2 >> Battery voltage exists for more than a few seconds: GO TO 12.

9.CHECK ECM POWER SUPPLY CIRCUIT-IV

1.
2.

Turn ignition switch OFF and wait at least 10 seconds.

Check the voltage between ECM harness connector and ground.
ECM
Connector

Terminal

F101

24

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 10.
NO
>> GO TO 12.

10.CHECK ECM POWER SUPPLY CIRCUIT-V

1.
2.
3.

Disconnect ECM harness connector.

Disconnect IPDM E/R harness connector E7.
Check the continuity between ECM harness connector and IPDM E/R harness connector.
ECM

4.

IPDM E/R

Connector

Terminal

Connector

Terminal

M107

125

E7

49

Continuity
Existed

Also check harness for short to ground and short to power.

Revision: 2007 June

EC-141

G37 Coupe

POWER SUPPLY AND GROUND CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 18.
NO
>> GO TO 11.

11.DETECT MALFUNCTIONING PART

Check the following.
Harness or connectors E106, M6
Harness for open or short between ECM and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.

12.CHECK ECM POWER SUPPLY CIRCUIT-VI

1.
2.
3.

Disconnect ECM harness connector.

Disconnect IPDM E/R harness connector E7.
Check the continuity between ECM harness connector and IPDM E/R harness connector.
ECM

IPDM E/R

Connector

Terminal

Connector

Terminal

F101

24

E7

69

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 13.

13.DETECT MALFUNCTIONING PART

Check the following.
Harness or connectors E3, F1
Harness connectors F104, F105
Harness for open or short between ECM and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.

14.CHECK 15A FUSE

1. Disconnect 15A fuse (No. 50) from IPDM E/R.
2. Check 15A fuse.
Is the inspection result normal?
YES >> GO TO 18.
NO
>> Replace 15A fuse.

15.CHECK GROUND CONNECTION-II

Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 16.
NO
>> Repair or replace ground connection.

16.CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II

1.
2.

Disconnect ECM harness connector.

Check the continuity between ECM harness connector and ground.

Revision: 2007 June

EC-142

G37 Coupe

POWER SUPPLY AND GROUND CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

Terminal

F101

Ground

Continuity

EC

123
M107

124

Ground

Existed

127
128

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 18.
NO
>> GO TO 17.

17.DETECT MALFUNCTIONING PART

Check the following.
Harness or connectors F103, M116
Harness for open or short between ECM and ground

>> Repair open circuit or short to power in harness or connectors.

18.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

Revision: 2007 June

EC-143

G37 Coupe

U0113, U1003 CAN COMM CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

U0113, U1003 CAN COMM CIRCUIT

Description

INFOID:0000000001736729

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. ECM and
VVEL control module are connected with two communication lines (CAN H line and CAN L line) and transmit/
receive data. ECM shares information and links with the VVEL control module during operation.

DTC Logic

INFOID:0000000001736730

DTC DETECTION LOGIC

NOTE:
If DTC U0113 or U1003 is displayed with DTC U1011, first perform the trouble diagnosis for DTC U1011.
Refer to EC-148, "DTC Logic".
DTC No.

Trouble diagnosis name

DTC detecting condition

U0113
Lost communication with VVEL control
module
U1003

CAN communication signal of OBD

(emission related diagnosis) is not received VVEL control module and ECM
for 2 seconds or more .
CAN communication signal other than
OBD (emission related diagnosis) is
not received between VVEL control
module and ECM for 2 seconds or
more .

Possible cause

Harness or connectors
(VVEL CAN communication line is
open or shorted)
ECM
VVEL control module

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-144, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736732

1.CHECK VVEL CAN COMMUNICATION CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Disconnect VVEL control module harness connector.
Check the continuity between ECM harness connector and VVEL control module harness connector.
ECM
Connector
F102

VVEL control module

Terminal
54
55

Connector
E15

Terminal
24
11

Continuity

Existed

5. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 2.
Revision: 2007 June

EC-144

G37 Coupe

U0113, U1003 CAN COMM CIRCUIT

< COMPONENT DIAGNOSIS >
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]

2.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

EC

3.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".

>> GO TO 4.
E

4.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-144, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-144, "DTC Logic".
Is the DTC U1003 displayed again?
YES >> GO TO 5.
NO
>> INSPECTION END
1.
2.
3.
4.

5.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Revision: 2007 June

EC-145

G37 Coupe

U1000, U1001 CAN COMM CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

U1000, U1001 CAN COMM CIRCUIT

Description

INFOID:0000000001733971

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.

DTC Logic

INFOID:0000000001733972

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis
name

U1000
CAN communication
line
U1001

DTC detecting condition

When ECM is not transmitting or receiving CAN communication signal of OBD (emission related diagnosis) for 2 seconds or more.
When ECM is not transmitting or receiving CAN communication signal other than OBD (emission related
diagnosis) for 2 seconds or more.

Possible cause

Harness or connectors
(CAN communication line is open or
shorted)

DTC CONFIRMATION PROCEDURE

1.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.
2. Check DTC.
Is DTC detected?
YES >> EC-146, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001733973

Go to LAN-16, "Trouble Diagnosis Flow Chart".

Revision: 2007 June

EC-146

G37 Coupe

U1010 CONTROL UNIT (CAN)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

U1010 CONTROL UNIT (CAN)

Description

INFOID:0000000001910713

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul- EC
tiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring. C
Each control unit transmits/receives data but selectively reads required data only.

DTC Logic

INFOID:0000000001733975

DTC DETECTION LOGIC

E
DTC No.
U1010

Trouble diagnosis name

CAN communication bus

DTC detecting condition

When detecting error during the initial diagnosis of CAN controller of ECM.

Possible cause
ECM

DTC CONFIRMATION PROCEDURE

1.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-147, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001733976

1.INSPECTION START

With CONSULT-III
1. Turn ignition switch ON.
2. Select SELF-DIAG RESULTS mode with CONSULT-III.
3. Touch ERASE.
4. Perform DTC Confirmation Procedure.
See EC-147, "DTC Logic".
5. Check DTC.
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-147, "DTC Logic".
4. Check DTC.
Is the DTC U1010 displayed again?
YES >> GO TO 2.
NO
>> INSPECTION END

2.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Revision: 2007 June

EC-147

G37 Coupe

U1011 CONTROL UNIT (CAN)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

U1011 CONTROL UNIT (CAN)

Description

INFOID:0000000001910711

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. ECM and
VVEL control module are connected with two communication lines (CAN H line and CAN L line) and transmit/
receive data. ECM shares information and links with the VVEL control module during operation.

DTC Logic

INFOID:0000000001736735

DTC DETECTION LOGIC

DTC No.
U1011

Trouble diagnosis name

VVEL CAN controller

DTC detecting condition

When detecting error during the initial diagnosis of VVEL CAN controller
of ECM.

Possible cause
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-148, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736741

1.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-148, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-148, "DTC Logic".
Is the DTC U1011 displayed again?
YES >> GO TO 2.
NO
>> INSPECTION END
1.
2.
3.
4.

2.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Revision: 2007 June

EC-148

G37 Coupe

U1024 CAN COMM CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

U1024 CAN COMM CIRCUIT

Description

INFOID:0000000001910712

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul- EC
tiplex communication line with high data communication speed and excellent error detection ability. ECM and
VVEL control module are connected with two communication lines (CAN H line and CAN L line) and transmit/
receive data. ECM shares information and links with the VVEL control module during operation.
C

DTC Logic

INFOID:0000000001736736

DTC DETECTION LOGIC

NOTE:
If DTC U1024 is displayed with DTC U1011, first perform the trouble diagnosis for DTC U1011.
Refer to EC-148, "DTC Logic".
DTC No.

Trouble diagnosis name

U1024

VVEL CAN communication

DTC detecting condition

Possible cause

When VVEL control module cannot

transmit/receive can communication
signal from ECM.
When detecting error during the initial diagnosis of CAN controller of
VVEL control module.

Harness or connectors
(CAN communication line is open or
shorted)
ECM
VVEL control module

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-149, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736743

1.CHECK VVEL CAN COMMUNICATION CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Disconnect VVEL control module harness connector.
Check the continuity between ECM harness connector and VVEL control module harness connector.
ECM
Connector
F102

VVEL control module

Terminal
54
55

Connector

Terminal

E15

24
11

Continuity

Existed

5. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

2.CHECK INTERMITTENT INCIDENT

Revision: 2007 June

EC-149

G37 Coupe

U1024 CAN COMM CIRCUIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-149, "DTC Logic".

With GST
Turn ignition switch ON.
Select Service $04 with GST.
Perform DTC Confirmation Procedure.
See EC-149, "DTC Logic".
Is the DTC U1024 displayed again?
YES >> GO TO 5.
NO
>> INSPECTION END
1.
2.
3.

5.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Revision: 2007 June

EC-150

G37 Coupe

P0011, P0021 IVT CONTROL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0011, P0021 IVT CONTROL

DTC Logic

INFOID:0000000001733977

DTC DETECTION LOGIC

EC

NOTE:
If DTC P0011 or P0021 is displayed with DTC P0075 or P0081, first perform the trouble diagnosis for
DTC P0075, P0081. Refer to EC-162, "DTC Logic".
If DTC P0011 or P0021 is displayed with DTC P0524, first perform the trouble diagnosis for DTC
P0524. Refer to EC-343, "DTC Logic".

Trouble diagnosis
name

DTC No.

P0011

Intake valve timing

control performance
(bank 1)

P0021

Intake valve timing

control performance
(bank 2)

Detecting condition

There is a gap between angle of target and

phase-control angle degree.

Possible cause

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)
Intake valve control solenoid valve
Accumulation of debris to the signal pick-up
portion of the camshaft
Timing chain installation
Foreign matter caught in the oil groove for intake valve timing control

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10V and 16V at
idle.
>> GO TO 2.

With CONSULT-III
Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
Start engine and warm it up to the normal operating temperature.
Maintain the following conditions for at least 6 consecutive seconds. Hold the accelerator pedal as steady
as possible.

VHCL SPEED SE

100 - 120 km/h (63 - 75 mph)

ENG SPEED

1,200 - 2,000 rpm

COOLAN TEMP/S

More than 60C (140F)

B/FUEL SCHDL

More than 7.3 msec

Selector lever

D position (A/T)
5th position (M/T)

CAUTION:
Always drive at a safe speed.
4. Stop vehicle with engine running and let engine idle for 10 seconds.
5. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-152, "Diagnosis Procedure"
Revision: 2007 June

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1.
2.
3.

EC-151

G37 Coupe

P0011, P0021 IVT CONTROL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE-II

1.
2.

With CONSULT-III
Select DATA MONITOR mode with CONSULT-III.
Maintain the following conditions for at least 20 consecutive seconds.

ENG SPEED

1,700 - 3,175 rpm (A constant rotation is maintained.)

COOLAN TEMP/S

More than 70C (158F)

Selector lever

1st or 2nd position

Driving location uphill

Driving vehicle uphill

(Increased engine load will help maintain the driving
conditions required for this test.)

CAUTION:
Always drive at a safe speed.
3. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-152, "Diagnosis Procedure"
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001733978

1.CHECK OIL PRESSURE WARNING LAMP

1.
2.

Start engine.
Check oil pressure warning lamp and confirm it is not illuminated.
Is oil pressure warning lamp illuminated?
YES >> Go to LU-6, "Inspection".
NO
>> GO TO 2.

PBIA8559J

2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE

Refer to EC-153, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

3.CHECK CRANKSHAFT POSITION SENSOR (POS)

Refer to EC-267, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Replace crankshaft position sensor (POS).

4.CHECK CAMSHAFT POSITION SENSOR (PHASE)

Refer to EC-271, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace malfunctioning camshaft position sensor (PHASE).

Revision: 2007 June

EC-152

G37 Coupe

P0011, P0021 IVT CONTROL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

5.CHECK CAMSHAFT (INTAKE)

Check the following.

Accumulation of debris to the signal plate of camshaft front end
Chipping signal plate of camshaft front end
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Remove debris and clean the signal plate of camshaft
front end or replace camshaft.

EC

D
JMBIA0962ZZ

6.CHECK TIMING CHAIN INSTALLATION

Check service records for any recent repairs that may cause timing chain misaligned.
Are there any service records that may cause timing chain misaligned?
YES >> Check timing chain installation. Refer to EM-49, "Removal and Installation".
NO
>> GO TO 7.

7.CHECK LUBRICATION CIRCUIT

Perform Inspection of Camshaft Sprocket (INT) Oil Groove. Refer to EM-93, "Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Clean lubrication line.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001733979

1.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect intake valve timing control solenoid valve harness connector.
Check resistance between intake valve timing control solenoid valve terminals as follows.
Terminals

Resistance

1 and 2

7.0 - 7.7 [at 20C (68F)]

1 or 2 and ground

(Continuity should not exist)

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-II

1.

Remove intake valve timing control solenoid valve.

P

Revision: 2007 June

EC-153

G37 Coupe

P0011, P0021 IVT CONTROL

< COMPONENT DIAGNOSIS >
2. Provide 12V DC between intake valve timing control solenoid
valve terminals 1 and 2, and then interrupt it. Make sure that the
plunger moves as shown in the figure.
CAUTION:
Do not apply 12V DC continuously for 5 seconds or more.
Doing so may result in damage to the coil in intake valve
timing control solenoid valve.
NOTE:
Always replace O-ring when intake valve timing control
solenoid valve is removed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

Revision: 2007 June

EC-154

[VQ37VHR]

JMBIA0079ZZ

G37 Coupe

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

Description

A
INFOID:0000000001733983

SYSTEM DESCRIPTION
Sensor

EC
Input Signal to ECM

ECM function

Actuator

Air fuel ratio (A/F) sensor 1

heater control

Air fuel ratio (A/F) sensor 1

heater

Camshaft position sensor (PHASE)

Crankshaft position sensor (POS)

Engine speed

Mass air flow sensor

Amount of intake air

The ECM performs ON/OFF duty control of the A/F sensor 1 heater corresponding to the engine operating
condition to keep the temperature of A/F sensor 1 element at the specified range.

DTC Logic

INFOID:0000000001733984

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0031

Air fuel ratio (A/F) sensor

1 heater (bank 1) control
circuit low

The current amperage in the A/F sensor 1 heater

circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)
A/F sensor 1 heater

P0032

Air fuel ratio (A/F) sensor

1 heater (bank 1) control
circuit high

The current amperage in the A/F sensor 1 heater

circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)
A/F sensor 1 heater

P0051

Air fuel ratio (A/F) sensor

1 heater (bank 2) control
circuit low

The current amperage in the A/F sensor 1 heater

circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)
A/F sensor 1 heater

P0052

Air fuel ratio (A/F) sensor

1 heater (bank 2) control
circuit high

The current amperage in the A/F sensor 1 heater

circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)
A/F sensor 1 heater

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10.5V and 16V at
idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-156, "Diagnosis Procedure".
NG
>> INSPECTION END

Revision: 2007 June

EC-155

G37 Coupe

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001733985

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect air fuel ratio (A/F) sensor 1 harness connector.

Turn ignition switch ON.
Check the voltage between A/F sensor 1 harness connector and ground.
A/F sensor 1

DTC

Bank

Connector

Terminal

P0031, P0032

F3

P0051, P0052

F20

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between A/F sensor 1 and fuse
>> Repair or replace harness or connectors.

4.CHECK A/F SENSOR 1 HEATER OUTPUT SIGNAL CIRCUIT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

DTC

A/F sensor 1

ECM

Bank

Connector

Terminal

P0031, P0032

F3

P0051, P0052

F20

Connector

Terminal
1

F101

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK A/F SENSOR 1 HEATER

Refer to EC-157, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Revision: 2007 June

EC-156

G37 Coupe

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

[VQ37VHR]
< COMPONENT DIAGNOSIS >
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

EC

>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

C

Perform GI-38, "Intermittent Incident".

>> Repair or replace.

Component Inspection

INFOID:0000000001733986

1.CHECK AIR FUEL RATIO (A/F) SENSOR 1

1.
2.
3.

Turn ignition switch OFF.

Disconnect A/F sensor 1 harness connector.
Check resistance between A/F sensor 1 terminals as follows.
Terminal

Resistance

3 and 4

1.8 - 2.44 [at 25C (77F)]

3 and 1, 2

(Continuity should not exist)

4 and 1, 2

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any air fuel ratio (A/F) sensor which has been dropped from a height of more than 0.5 m
(19.7 in) onto a hard surface such as a concrete floor; use a new one.
Before installing new air fuel ratio (A/F) sensor, clean exhaust system threads using Heated Oxygen
Sensor Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

Revision: 2007 June

EC-157

G37 Coupe

P0037, P0038, P0057, P0058 HO2S2 HEATER

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0037, P0038, P0057, P0058 HO2S2 HEATER

Description

INFOID:0000000001733987

SYSTEM DESCRIPTION
Sensor

Input signal to ECM

Camshaft position sensor (PHASE)

Crankshaft position sensor (POS)

Engine speed

Engine coolant temperature sensor

Engine coolant temperature

Mass air flow sensor

Amount of intake air

ECM function

Actuator

Heated oxygen sensor 2

heater control

Heated oxygen sensor 2 heater

The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.

OPERATION
Engine speed rpm

Heated oxygen sensor 2 heater

Above 3,600

OFF

Below 3,600 rpm after the following conditions are met.

Engine: After warming up
Keeping the engine speed between 3,500 and 4,000 rpm for 1
minute and at idle for 1 minute under no load

ON

DTC Logic

INFOID:0000000001733988

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0037

Heated oxygen sensor 2

heater (bank 1) control
circuit low

The current amperage in the heated oxygen sensor 2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.)

Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
Heated oxygen sensor 2 heater

P0038

Heated oxygen sensor 2

heater (bank 1) control
circuit high

The current amperage in the heated oxygen sensor 2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.)

Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
Heated oxygen sensor 2 heater

P0057

Heated oxygen sensor 2

heater (bank 2) control
circuit low

The current amperage in the heated oxygen sensor 2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.)

Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
Heated oxygen sensor 2 heater

P0058

Heated oxygen sensor 2

heater (bank 2) control
circuit high

The current amperage in the heated oxygen sensor 2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.)

Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
Heated oxygen sensor 2 heater

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 11V and 16V at
idle.
>> GO TO 2.
Revision: 2007 June

EC-158

G37 Coupe

P0037, P0038, P0057, P0058 HO2S2 HEATER

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.PERFORM DTC CONFIRMATION PROCEDURE

A
With CONSULT-III
1. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
EC
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load. C
7. Let engine idle for 1 minute.
8. Check 1st trip DTC.
With GST
D
Follow the procedure With CONSULT-III above.
Is 1st tip DTC detected?
YES >> Go to EC-159, "Diagnosis Procedure".
E
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001733989

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK HO2S2 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect heated oxygen sensor 2 harness connector.

Turn ignition switch ON.
Check the voltage between HO2S2 harness connector and ground.

J
HO2S2

DTC

Bank

Connector

Terminal

P0037, P0038

F54

P0057, P0058

F53

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between heated oxygen sensor 2 and fuse

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK HO2S2 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between HO2S2 harness connector and ECM harness connector.

Revision: 2007 June

EC-159

G37 Coupe

P0037, P0038, P0057, P0058 HO2S2 HEATER

[VQ37VHR]

< COMPONENT DIAGNOSIS >

HO2S2

DTC

ECM

Bank

Connector

Terminal

P0037, P0038

F54

P0057, P0058

F53

Connector

Terminal
17

F101

33

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK HEATED OXYGEN SENSOR 2 HEATER

Refer to EC-160, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001733990

1.CHECK HEATED OXYGEN SENSOR 2 HEATER

1.
2.
3.

Turn ignition switch OFF.

Disconnect heated oxygen sensor 2 harness connector.
Check resistance between HO2S2 terminals as follows.
Terminal

Resistance

2 and 3

3.4 - 4.4 [at 25C (77F)]

1 and 2, 3, 4

(Continuity should not exist)

4 and 1, 2, 3

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

Revision: 2007 June

EC-160

G37 Coupe

P0037, P0038, P0057, P0058 HO2S2 HEATER

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> INSPECTION END

EC

Revision: 2007 June

EC-161

G37 Coupe

P0075, P0081 IVT CONTROL SOLENOID VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0075, P0081 IVT CONTROL SOLENOID VALVE

Description

INFOID:0000000001733991

Intake valve timing control solenoid valve is activated by ON/OFF

pulse duty (ratio) signals from the ECM.
The intake valve timing control solenoid valve changes the oil
amount and direction of flow through intake valve timing control unit
or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
PBIB1842E

DTC Logic

INFOID:0000000001733992

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

DTC detecting condition

P0075

Intake valve timing control solenoid valve (bank 1) circuit

P0081

Intake valve timing control solenoid valve (bank 2) circuit

An improper voltage is sent to the ECM

through intake valve timing control solenoid
valve.

Possible cause
Harness or connectors
(Intake valve timing control solenoid
valve circuit is open or shorted.)
Intake valve timing control solenoid
valve

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-162, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001733993

1.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect intake valve timing control solenoid valve harness connector.
Turn ignition switch ON.
Check the voltage between intake valve timing control solenoid valve harness connector and ground.

DTC

IVT control solenoid valve

Bank

Connector

Terminal

P0075

F28

P0081

F29

Revision: 2007 June

Ground

Voltage

Ground

Battery voltage

EC-162

G37 Coupe

P0075, P0081 IVT CONTROL SOLENOID VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 3.
NO
>> GO TO 2.

2.DETECT MALFUNCTIONING PART

EC

Check the following.

Harness connectors E3, F1
Harness for open or short between intake valve timing control solenoid valve and IPDM E/R

>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN

AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between intake valve timing control solenoid valve harness connector and ECM harness connector.

F
DTC

IVT control solenoid valve

Bank

Connector

Terminal

P0075

F28

P0081

F29

ECM
Connector

Terminal
18

F101

29

Continuity

G
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE

Refer to EC-163, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

5.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001910714

1.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect intake valve timing control solenoid valve harness connector.
Check resistance between intake valve timing control solenoid valve terminals as follows.

O
Terminals

Resistance

1 and 2

7.0 - 7.7 [at 20C (68F)]

1 or 2 and ground

(Continuity should not exist)

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-II

1.

Remove intake valve timing control solenoid valve.

Revision: 2007 June

EC-163

G37 Coupe

P0075, P0081 IVT CONTROL SOLENOID VALVE

< COMPONENT DIAGNOSIS >
2. Provide 12V DC between intake valve timing control solenoid
valve terminals 1 and 2, and then interrupt it. Make sure that the
plunger moves as shown in the figure.
CAUTION:
Do not apply 12V DC continuously for 5 seconds or more.
Doing so may result in damage to the coil in intake valve
timing control solenoid valve.
NOTE:
Always replace O-ring when intake valve timing control
solenoid valve is removed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

Revision: 2007 June

EC-164

[VQ37VHR]

JMBIA0079ZZ

G37 Coupe

P0101, P010B MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0101, P010B MAF SENSOR

Description

INFOID:0000000001733999

The mass air flow sensor (1) is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sensor controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.

EC

PBIA9559J

DTC Logic

INFOID:0000000001734000

DTC DETECTION LOGIC

DTC No.

P0101

P010B

Trouble diagnosis name

DTC detecting condition

Possible cause
Harness or connectors
(The sensor circuit is open or
shorted.)
Mass air flow sensor
EVAP control system pressure
sensor

A)

A high voltage from the sensor is sent to ECM

under light load driving condition.

B)

Harness or connectors
(The sensor circuit is open or
shorted.)
A low voltage from the sensor is sent to ECM un- Intake air leaks
Mass air flow sensor
der heavy load driving condition.
EVAP control system pressure
sensor
Intake air temperature sensor

A)

A high voltage from the sensor is sent to ECM

under light load driving condition.

Harness or connectors
(The sensor circuit is open or
shorted.)
Mass air flow sensor
EVAP control system pressure
sensor

B)

Harness or connectors
(The sensor circuit is open or
shorted.)
A low voltage from the sensor is sent to ECM un- Intake air leaks
Mass air flow sensor
der heavy load driving condition.
EVAP control system pressure
sensor
Intake air temperature sensor

Mass air flow sensor

(bank 1) circuit range/
performance

Mass air flow sensor

(bank 2) circuit range/
performance

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
If engine will not start or stops soon, wait at least 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.

Revision: 2007 June

EC-165

G37 Coupe

P0101, P010B MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

1. Start engine and warm it up to normal operating temperature.
2. Run engine for at least 10 seconds at idle speed.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-167, "Diagnosis Procedure".
NO-1 >> With CONSULT-III: GO TO 3.
NO-2 >> Without CONSULT-III: GO TO 5.

3.CHECK MASS AIR FLOW SENSOR FUNCTION

1.
2.

Turn ignition switch ON.

Start engine and warm it up to normal operating temperature.
If engine cannot be started, go to EC-167, "Diagnosis Procedure".
3. Select DATA MONITOR mode with CONSULT-III.
4. Check the voltage of MAS A/F SE-B1/B2 with DATA MONITOR.
5. Increases engine speed to about 4,000 rpm.
6. Monitor the linear voltage rise in response to engine speed
increases.
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Go to EC-167, "Diagnosis Procedure".

PBIB3457E

4.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B

1.

Maintain the following conditions for at least 10 consecutive seconds.

ENG SPEED

More than 2,000 rpm

TP SEN 1-B1

More than 3V

TP SEN 2-B1

More than 3V

TP SEN 1-B2

More than 3V

TP SEN 2-B2

More than 3V

Selector lever

Suitable position

Driving location

Driving vehicle uphill (Increased engine load) will help

maintain the driving conditions required for this test.

CAUTION:
Always drive vehicle at a safe speed.
2. Check 1st rip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-167, "Diagnosis Procedure".
NO
>> INSPECTION END
Revision: 2007 June

EC-166

G37 Coupe

P0101, P010B MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

5.PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B

A
Perform component function check. Refer to EC-167, "Component Function Check".
NOTE:
Use component function check to check the overall function of the mass air flow sensor circuit. During this
EC
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
C
NO
>> Go to EC-167, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734001

1.PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B

With GST
Start engine and warm it up to normal operating temperature.
Select Service $01 with GST.
Check the mass air flow sensor signal with Service $01.
Check for linear mass air flow sensor signal value rise in
response to increases to about 4,000 rpm in engine speed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-167, "Diagnosis Procedure".

1.
2.
3.
4.

H
SEF534P

Diagnosis Procedure

INFOID:0000000001734002

1.INSPECTION START

Confirm the detected malfunction (A or B). Refer to EC-165, "DTC Logic".

Which malfunction is detected?
A
>> GO TO 3.
B
>> GO TO 2.

2.CHECK INTAKE SYSTEM

L

Check the following for connection.

Air duct
Vacuum hoses
Intake air passage between air duct and intake manifold
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Reconnect the parts.

3.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair or replace ground connection.

4.CHECK MAF SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect mass air flow (MAF) sensor harness connector.

Turn ignition switch ON.
Check the voltage between MAF sensor harness connector and ground.

Revision: 2007 June

EC-167

G37 Coupe

P0101, P010B MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

MAF sensor
Bank

Connector

Terminal

P0101

F31

P010B

F42

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness connectors M116, F103
Harness for open or short between mass air flow sensor and ECM
Harness for open or short between mass air flow sensor and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between MAF sensor harness connector and ECM harness connector.

DTC

MAF sensor

ECM

Bank

Connector

Terminal

P0101

F31

P010B

F42

Connector

Terminal
68

F102

94

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between MAF sensor harness connector and ECM harness connector.

DTC

MAF sensor

ECM

Bank

Connector

Terminal

P0101

F31

P010B

F42

Connector

Terminal
77

F102

79

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

8.CHECK INTAKE AIR TEMPERATURE SENSOR

Check intake air temperature sensor (bank 1).
Refer to EC-182, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace mass air flow sensor (bank 1) (with intake air temperature sensor).

9.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Revision: 2007 June

EC-168

G37 Coupe

P0101, P010B MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace EVAP control system pressure sensor.

10.CHECK MASS AIR FLOW SENSOR

EC

Refer to EC-169, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 11.
NO
>> Replace malfunctioning mass air flow sensor.

11.CHECK INTERMITTENT INCIDENT

D

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734003

1.CHECK MASS AIR FLOW SENSOR-I

1.
2.
3.
4.
5.

With CONSULT-III
Turn ignition switch OFF.
Reconnect all harness connectors disconnected.
Start engine and warm it up to normal operating temperature.
Connect CONSULT-III and select DATA MONITOR mode.
Select MAS A/F SE-B1 and MAS A/F SE-B2, and check the indication.
Monitor item

Condition

Indication

Ignition switch ON (Engine stopped.)

MAS A/F SE-B1
MAS A/F SE-B2

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

1.
2.
3.
4.

Without CONSULT-III
Turn ignition switch OFF.
Reconnect all harness connectors disconnected.
Start engine and warm it up to normal operating temperature.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

Ground

Condition

Voltage

Ignition switch ON (Engine stopped.)

F102

77 [MAF sensor (bank 1) signal]

79 [MAF sensor (bank 2) signal]

Ground

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal

operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

O
0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 2.

2.CHECK FOR THE CAUSE OF UNEVEN AIR FLOW THROUGH MASS AIR FLOW SENSOR
1.
2.
-

Turn ignition switch OFF.

Check for the cause of uneven air flow through mass air flow sensor. Refer to following.
Crushed air ducts

Revision: 2007 June

EC-169

G37 Coupe

P0101, P010B MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system parts
Is the inspection result normal?
YES >> GO TO 4.
NO
>> GO TO 3.

3.CHECK MASS AIR FLOW SENSOR-II

1.
2.
3.
4.

With CONSULT-III
Repair or replace malfunctioning part.
Start engine and warm it up to normal operating temperature.
Connect CONSULT-III and select DATA MONITOR mode.
Select MAS A/F SE-B1 and MAS A/F SE-B2, and check the indication.
Monitor item

Condition

Indication

Ignition switch ON (Engine stopped.)

MAS A/F SE-B1
MAS A/F SE-B2

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

1.
2.
3.

Without CONSULT-III
Repair or replace malfunctioning part.
Start engine and warm it up to normal operating temperature.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

Ground

Condition

Voltage

Ignition switch ON (Engine stopped.)

F102

77 [MAF sensor (bank 1) signal]

79 [MAF sensor (bank 2) signal]

Ground

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal

operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 4.

4.CHECK MASS AIR FLOW SENSOR-III

1.
2.
3.
4.
5.

With CONSULT-III
Turn ignition switch OFF.
Disconnect mass air flow sensor harness connector and reconnect it again.
Start engine and warm it up to normal operating temperature.
Connect CONSULT-III and select DATA MONITOR mode.
Select MAS A/F SE-B1 and MAS A/F SE-B2, and check the indication.
Monitor item

Condition

Indication

Ignition switch ON (Engine stopped.)

MAS A/F SE-B1
MAS A/F SE-B2

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Without CONSULT-III
Revision: 2007 June

EC-170

G37 Coupe

P0101, P010B MAF SENSOR

< COMPONENT DIAGNOSIS >
1. Turn ignition switch OFF.
2. Disconnect mass air flow sensor harness connector and reconnect it again.
3. Start engine and warm it up to normal operating temperature.
4. Check the voltage between ECM harness connector and ground.

[VQ37VHR]
A

EC
ECM
Connector

Terminal

Ground

Condition
Ignition switch ON (Engine stopped.)

F102

77 [MAF sensor (bank 1) signal]

79 [MAF sensor (bank 2) signal]

Ground

Voltage
Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal

operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

D
0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Clean or replace malfunctioning mass air flow sensor.

Revision: 2007 June

EC-171

G37 Coupe

P0102, P0103, P010C, P010D MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0102, P0103, P010C, P010D MAF SENSOR

Description

INFOID:0000000001910824

The mass air flow sensor (1) is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sensor controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
PBIA9559J

DTC Logic

INFOID:0000000001734005

DTC DETECTION LOGIC

Trouble diagnosis
name

DTC detecting condition

P0102

Mass air flow sensor

(bank 1) circuit low
input

An excessively low voltage from the sensor is sent

to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)
Intake air leaks
Mass air flow sensor

P0103

Mass air flow sensor

(bank 1) circuit high
input

An excessively high voltage from the sensor is

sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)
Mass air flow sensor

P010C

Mass air flow sensor

(bank 2) circuit low
input

An excessively low voltage from the sensor is sent

to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)
Intake air leaks
Mass air flow sensor

P010D

Mass air flow sensor

(bank 2) circuit high
input

An excessively high voltage from the sensor is

sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)
Mass air flow sensor

DTC No.

Possible cause

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Which DTC is detected?
P0102, P010C>>GO TO 2.
P0103, P010D>>GO TO 3.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0102 AND P010C

1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-173, "Diagnosis Procedure".
NO
>> INSPECTION END

3.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103 AND P010D-I

1.
2.

Turn ignition switch ON and wait at least 5 seconds.

Check DTC.

Revision: 2007 June

EC-172

G37 Coupe

P0102, P0103, P010C, P010D MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is DTC detected?
YES >> Go to EC-173, "Diagnosis Procedure".
NO
>> GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103 AND P010D-II

EC

1. Start engine and wait at least 5 seconds.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-173, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734006

1.INSPECTION START
E

Confirm the detected DTC.

Which DTC is detected?
P0102, P010C>>GO TO 2.
P0103, P010D>>GO TO 3.

2.CHECK INTAKE SYSTEM

Check the following for connection.
Air duct
Vacuum hoses
Intake air passage between air duct to intake manifold
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Reconnect the parts.

3.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair or replace ground connection.

4.CHECK MAF SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect mass air flow (MAF) sensor harness connector.

Turn ignition switch ON.
Check the voltage between MAF sensor harness connector and ground.

DTC

MAF sensor
Bank

Connector

Terminal

P0102, P0103

F31

P010C, P010D

F42

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E106, M6
Harness connectors M116, F103
Harness for open or short between mass air flow sensor and ECM
Harness for open or short between mass air flow sensor and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
Revision: 2007 June

EC-173

G37 Coupe

P0102, P0103, P010C, P010D MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

6.CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between MAF sensor harness connector and ECM harness connector.

DTC

MAF sensor

ECM

Bank

Connector

Terminal

P0102, P0103

F31

P010C, P010D

F42

Connector

Terminal
68

F102

94

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between MAF sensor harness connector and ECM harness connector.

DTC

MAF sensor

ECM

Bank

Connector

Terminal

P0102, P0103

F31

P010C, P010D

F42

Connector
F102

Terminal
77
79

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

8.CHECK MASS AIR FLOW SENSOR

Refer to EC-169, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace malfunctioning mass air flow sensor.

9.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910825

1.CHECK MASS AIR FLOW SENSOR-I

1.
2.
3.
4.
5.

With CONSULT-III
Turn ignition switch OFF.
Reconnect all harness connectors disconnected.
Start engine and warm it up to normal operating temperature.
Connect CONSULT-III and select DATA MONITOR mode.
Select MAS A/F SE-B1 and MAS A/F SE-B2, and check the indication.
Monitor item

Condition

Indication

Ignition switch ON (Engine stopped.)

MAS A/F SE-B1
MAS A/F SE-B2

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

Revision: 2007 June

0.7 - 1.2V to Approx. 2.4V*

EC-174

G37 Coupe

P0102, P0103, P010C, P010D MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

1.
2.
3.
4.

Without CONSULT-III
Turn ignition switch OFF.
Reconnect all harness connectors disconnected.
Start engine and warm it up to normal operating temperature.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

Ground

EC

Condition

Voltage

Ignition switch ON (Engine stopped.)

F102

77 [MAF sensor (bank 1) signal]

79 [MAF sensor (bank 2) signal]

Ground

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal

operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 2.

2.CHECK FOR THE CAUSE OF UNEVEN AIR FLOW THROUGH MASS AIR FLOW SENSOR
1. Turn ignition switch OFF.
2. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system parts
Is the inspection result normal?
YES >> GO TO 4.
NO
>> GO TO 3.

3.CHECK MASS AIR FLOW SENSOR-II

1.
2.
3.
4.

With CONSULT-III
Repair or replace malfunctioning part.
Start engine and warm it up to normal operating temperature.
Connect CONSULT-III and select DATA MONITOR mode.
Select MAS A/F SE-B1 and MAS A/F SE-B2, and check the indication.
Monitor item

Condition

Indication

Ignition switch ON (Engine stopped.)

MAS A/F SE-B1
MAS A/F SE-B2

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Without CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal operating temperature.
3. Check the voltage between ECM harness connector and ground.

Revision: 2007 June

EC-175

G37 Coupe

P0102, P0103, P010C, P010D MAF SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

Terminal

Ground

Condition

Voltage

Ignition switch ON (Engine stopped.)

F102

77 [MAF sensor (bank 1) signal]

79 [MAF sensor (bank 2) signal]

Ground

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal

operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 4.

4.CHECK MASS AIR FLOW SENSOR-III

1.
2.
3.
4.
5.

With CONSULT-III
Turn ignition switch OFF.
Disconnect mass air flow sensor harness connector and reconnect it again.
Start engine and warm it up to normal operating temperature.
Connect CONSULT-III and select DATA MONITOR mode.
Select MAS A/F SE-B1 and MAS A/F SE-B2, and check the indication.
Monitor item

Condition

Indication

Ignition switch ON (Engine stopped.)

MAS A/F SE-B1
MAS A/F SE-B2

Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Without CONSULT-III
1. Turn ignition switch OFF.
2. Disconnect mass air flow sensor harness connector and reconnect it again.
3. Start engine and warm it up to normal operating temperature.
4. Check the voltage between ECM harness connector and ground.
ECM
Connector

Terminal

Ground

Condition
Ignition switch ON (Engine stopped.)

F102

77 [MAF sensor (bank 1) signal]

79 [MAF sensor (bank 2) signal]

Ground

Voltage
Approx. 0.4V

Idle (Engine is warmed-up to normal operating temperature.)

0.7 - 1.2V

2,500 rpm (Engine is warmed-up to normal

operating temperature.)

1.3 - 1.7V

Idle to about 4,000 rpm

0.7 - 1.2V to Approx. 2.4V*

*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Clean or replace malfunctioning mass air flow sensor.

Revision: 2007 June

EC-176

G37 Coupe

P010A MANIFOLD ABSOLUTE PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P010A MANIFOLD ABSOLUTE PRESSURE SENSOR

Description

INFOID:0000000001736745

The manifold absolute pressure (MAP) sensor is placed at intake

manifold collector. It detects intake manifold pressure and sends the
voltage signal to the ECM.
The sensor uses a silicon diaphragm which is sensitive to the
change in pressure. As the pressure increases, the voltage rises.

EC

JMBIA0877ZZ

DTC Logic

INFOID:0000000001736746

DTC DETECTION LOGIC

NOTE:
If DTC P010A is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-358, "DTC Logic".

DTC No.

P010A

Trouble diagnosis name

Manifold absolute pressure sensor

circuit

DTC detecting condition

An excessively low voltage from
the sensor is sent to ECM.
An excessively high voltage from
the sensor is sent to ECM.

Possible cause
Harness or connectors
(The sensor circuit is open or
shorted.)
Manifold absolute pressure (MAP)
sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 10 seconds.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-177, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736747

1.CHECK GROUND CONNECTION

P

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK MAP SENSOR POWER SUPPLY CIRCUIT

1.

Disconnect MAP sensor harness connector.

Revision: 2007 June

EC-177

G37 Coupe

P010A MANIFOLD ABSOLUTE PRESSURE SENSOR

< COMPONENT DIAGNOSIS >
2. Turn ignition switch ON.
3. Check the voltage between MAP sensor harness connector and ground.
MAP sensor
Connector

Terminal

F50

Ground

Voltage

Ground

Approx. 5V

[VQ37VHR]

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK MAP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between MAP sensor harness connector and ECM harness connector.
MAP sensor

ECM

Connector

Terminal

Connector

Terminal

F50

F102

96

Continuity
Existed

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK MAP SENSOR INTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between MAP sensor harness connector and ECM harness connector.
MAP sensor

ECM

Connector

Terminal

Connector

Terminal

F50

F101

38

Continuity
Existed

2. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK MAP SENSOR

Refer to EC-178, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace MAP sensor.

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001736748

1.CHECK MAP SENSOR-I

1.
2.
3.
4.

Turn ignition switch OFF.

Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
Check the voltage between ECM harness connector terminals as follows.

Revision: 2007 June

EC-178

G37 Coupe

P010A MANIFOLD ABSOLUTE PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
+

5.

6.

Connector

Terminal

Connector

Terminal

F101

38

F102

96

EC

NOTE:
To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engine
is stopped.
Because the sensor is absolute pressure sensor, output value may differ depending on atmospheric
pressure and altitude.
Measure the atmospheric pressure.
NOTE:
As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the
pressure with the following chart.
Altitude

Compensated pressure

0m

0hPa

200m

-24hPa

400m

-47hPa

600m

-70hPa

800m

-92hPa

1000m

-114hPa

1500m

-168hPa

2000m

-218hPa

Voltage

800hPa

3.1 3.7V

850hPa

3.3 3.9V

900hPa

3.5 4.1V

950hPa

3.8 4.3V

1000hPa

4.0 4.6V

1050hPa

4.2 4.8V

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Replace MAP sensor.

JMBIA0870GB

2.CHECK MAP SENSOR-II

1.
2.
3.

Check the manifold absolute pressure sensor value corresponding to the atmospheric pressure.
Atmospheric pressure

Start engine and let it idle.

Check intake manifold vacuum.
Check the voltage between ECM harness connector terminals as follows.

ECM
+

4.

Connector

Terminal

Connector

Terminal

F101

38

F102

96

Confirm the difference of the voltage when engine is stopped and at idling is within the values shown in
the following chart.

Revision: 2007 June

EC-179

G37 Coupe

P010A MANIFOLD ABSOLUTE PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Intake manifold vacuum

Voltage difference

-40kPa(-300mmHg)

1.5 2.0V

-53.3kPa(-400mmHg)

2.0 2.6V

-66.7kPa(-500mmHg)

2.6 3.2V

-80kPa(-600mmHg)

3.2 3.8V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace MAP sensor.

Revision: 2007 June

EC-180

G37 Coupe

P0112, P0113 IAT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0112, P0113 IAT SENSOR

Description

INFOID:0000000001734008

The intake air temperature sensor is built-into mass air flow sensor
(1). The sensor detects intake air temperature and transmits a signal
to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.
NOTE:
ECM uses only the intake air temperature sensor (bank 1) for engine
control and self-diagnosis. It does not use the intake air temperature
sensor (bank 2).

EC

PBIA9559J

<Reference data>
F
Intake air temperature
C (F)

Voltage*

Resistance k

25 (77)

3.3

1.800 - 2.200

80 (176)

1.2

0.283 - 0.359

*: These data are reference values and are measured between ECM terminal 67
(Intake air temperature sensor) and ground.

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing
so may result in damage to the ECMs transistor. Use a ground other than ECM
terminals, such as the ground.

DTC Logic

SEF012P

I
INFOID:0000000001734009

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

DTC detecting condition

P0112

Intake air temperature sensor

(bank 1) circuit low input

An excessively low voltage from the sensor is

sent to ECM.

P0113

Intake air temperature sensor

(bank 1) circuit high input

An excessively high voltage from the sensor is

sent to ECM.

Possible cause

Harness or connectors
(The sensor circuit is open or shorted.)
Intake air temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 5 seconds.

2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-182, "Diagnosis Procedure".
NO
>> INSPECTION END
Revision: 2007 June

EC-181

G37 Coupe

P0112, P0113 IAT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001734010

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK INTAKE AIR TEMPERATURE SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect mass air flow sensor (intake air temperature sensor is built-into) (bank 1) harness connector.
Turn ignition switch ON.
Check the voltage between mass air flow sensor (bank 1) harness connector and ground.
MAF sensor (bank 1)

Connector

Terminal

F31

Ground

Voltage

Ground

Approx. 5

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK INTAKE AIR TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between mass air flow sensor (bank 1) harness connector and ECM harness connector.
MAF sensor (bank 1)

ECM

Connector

Terminal

Connector

Terminal

F31

F102

68

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK INTAKE AIR TEMPERATURE SENSOR

Refer to EC-182, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace mass air flow sensor (with intake air temperature sensor) (bank 1).

5.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734011

1.CHECK INTAKE AIR TEMPERATURE SENSOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect mass air flow sensor (bank 1) harness connector.
Check resistance between mass air flow sensor (bank 1) terminals as follows.

Revision: 2007 June

EC-182

G37 Coupe

P0112, P0113 IAT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Terminals
1 and 2

Condition
Temperature C (F)

Resistance
25 (77)

1.800 - 2.200 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace mass air flow sensor (with intake air temperature sensor) (bank 1).

EC

Revision: 2007 June

EC-183

G37 Coupe

P0117, P0118 ECT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0117, P0118 ECT SENSOR

Description

INFOID:0000000001734012

The engine coolant temperature sensor is used to detect the engine

coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

SEF594K

<Reference data>
Engine coolant temperature
C (F)

Voltage*

Resistance

10 (14)

4.4

7.0 - 11.4

20 (68)

3.5

2.37 - 2.63

50 (122)

2.2

0.68 - 1.00

90 (194)

0.9

0.236 - 0.260

*: These data are reference values and are measured between ECM terminal 71
(Engine coolant temperature sensor) and ground.

SEF012P

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000001734013

DTC DETECTION LOGIC

DTC No.

Trouble Diagnosis
Name

DTC Detecting Condition

P0117

Engine coolant temperature sensor circuit low input

An excessively low voltage from the sensor is

sent to ECM.

P0118

Engine coolant temperature sensor circuit high input

An excessively high voltage from the sensor is

sent to ECM.

Possible Cause

Harness or connectors
(The sensor circuit is open or shorted.)
Engine coolant temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.

Turn ignition switch ON and wait at least 5 seconds.

Check DTC.

Revision: 2007 June

EC-184

G37 Coupe

P0117, P0118 ECT SENSOR

< COMPONENT DIAGNOSIS >
Is DTC detected?
YES >> Go to EC-185, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

[VQ37VHR]
A

INFOID:0000000001734014

EC

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK ECT SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect engine coolant temperature (ECT) sensor harness connector.

Turn ignition switch ON.
Check the voltage between ECT sensor harness connector and ground.

F
ECT sensor
Connector

Terminal

F17

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

I

Check the following.

Harness connectors F106, F107
Harness for open or short between engine coolant temperature sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK ECT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ECT sensor harness connector and ECM harness connector.
ECT sensor

ECM

Connector

Terminal

Connector

Terminal

F17

F102

84

Continuity

M
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to EC-186, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace engine coolant temperature sensor.

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END
Revision: 2007 June

EC-185

G37 Coupe

P0117, P0118 ECT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Component Inspection

INFOID:0000000001734015

1.CHECK ENGINE COOLANT TEMPERATURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect engine coolant temperature sensor harness connector.
Remove engine coolant temperature sensor.
Check resistance between engine coolant temperature sensor
terminals by heating with hot water as shown in the figure.

Terminals

1 and 2

Condition

Temperature C (F)

Resistance
20 (68)

2.37 - 2.63 k

50 (122)

0.68 - 1.00 k

90 (194)

0.236 - 0.260 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace engine coolant temperature sensor.

Revision: 2007 June

EC-186

JMBIA0080ZZ

G37 Coupe

P0122, P0123, P0227, P0228 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0122, P0123, P0227, P0228 TP SENSOR

Description

A
INFOID:0000000001734016

Electric throttle control actuator consists of throttle control motor,

throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

EC

PBIB0145E

INFOID:0000000001734017

DTC DETECTION LOGIC

NOTE:
If DTC P0122, P0123, P0227 or P0228 is displayed with DTC P0643, first perform the trouble diagnosis
for DTC P0643. Refer to EC-358, "DTC Logic".

DTC No.

Trouble diagnosis name

DTC detecting condition

P0122

Throttle position sensor

2 (bank 1) circuit low input

An excessively low voltage from the TP sensor

2 is sent to ECM.

P0123

Throttle position sensor

2 (bank 1) circuit high input

An excessively high voltage from the TP sensor

2 is sent to ECM.

P0227

Throttle position sensor

2 (bank 2) circuit low input

An excessively low voltage from the TP sensor

2 is sent to ECM.

P0228

Throttle position sensor

2 (bank 2) circuit high input

An excessively high voltage from the TP sensor

2 is sent to ECM.

Possible cause

I
Harness or connectors
(TP sensor 2 circuit is open or shorted.)
Electric throttle control actuator
(TP sensor 2)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

P

1. Start engine and let it idle for 1 second.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-188, "Diagnosis Procedure".
NO
>> INSPECTION END

Revision: 2007 June

EC-187

G37 Coupe

P0122, P0123, P0227, P0228 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001734018

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect electric throttle control actuator harness connector.

Turn ignition switch ON.
Check the voltage between electric throttle control actuator harness connector and ground.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

P0122, P0123

F6

P0227, P0228

F27

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK THROTTLE POSITION SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

P0122, P0123

F6

P0227, P0228

F27

ECM
Connector

Terminal
40

F101

48

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK THROTTLE POSITION SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

P0122, P0123

F6

P0227, P0228

F27

ECM
Connector
F101

Terminal
34
35

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK THROTTLE POSITION SENSOR

Refer to EC-189, "Component Inspection".
Revision: 2007 June

EC-188

G37 Coupe

P0122, P0123, P0227, P0228 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

EC

Replace malfunctioning electric throttle control actuator.

Go to EC-189, "Special Repair Requirement".

>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

D

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734019

1.CHECK THROTTLE POSITION SENSOR

1.
2.
3.
4.
5.
6.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Perform EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
Turn ignition switch ON.
Set selector lever to D (A/T) or 1st (M/T) position.
Check the voltage between ECM harness connector and ground.

ECM
Connector

Terminal

Ground

Condition

30 [TP sensor 1 (bank 1)]

31 [TP sensor 1 (bank 2)]
F101

Ground

Accelerator pedal

34 [TP sensor 2 (bank 1)]

35 [TP sensor 2 (bank 2)]

Voltage

Fully released

More than 0.36V

Fully depressed

Less than 4.75V

Fully released

Less than 4.75V

Fully depressed

More than 0.36V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-189, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001734020

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"
>> END

Revision: 2007 June

EC-189

G37 Coupe

P0125 ECT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0125 ECT SENSOR

Description

INFOID:0000000001910832

The engine coolant temperature sensor is used to detect the engine

coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

SEF594K

<Reference data>
Engine coolant temperature
C (F)

Voltage*

Resistance

10 (14)

4.4

7.0 - 11.4

20 (68)

3.5

2.37 - 2.63

50 (122)

2.2

0.68 - 1.00

90 (194)

0.9

0.236 - 0.260

*: These data are reference values and are measured between ECM terminal 71
(Engine coolant temperature sensor) and ground.

SEF012P

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000001734022

DTC DETECTION LOGIC

NOTE:
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117 or
P0118. Refer to EC-184, "DTC Logic".
DTC No.

P0125

Trouble diagnosis name

DTC detecting condition

Insufficient engine coolant temperature for

closed loop fuel control

Voltage sent to ECM from the sensor is not

practical, even when some time has passed
after starting the engine.
Engine coolant temperature is insufficient for
closed loop fuel control.

Possible cause
Harness or connectors
(High resistance in the circuit)
Engine coolant temperature sensor
Thermostat

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.CHECK ENGINE COOLANT TEMPERATURE SENSOR FUNCTION

With CONSULT-III
Revision: 2007 June

EC-190

G37 Coupe

P0125 ECT SENSOR

< COMPONENT DIAGNOSIS >
1. Turn ignition switch ON.
2. Select DATA MONITOR mode with CONSULT-III.
3. Check that COOLAN TEMP/S is above 10C (50F).
With GST
Follow the procedure With CONSULT-III above.
Is it above 10C (50F)?
YES >> INSPECTION END
NO
>> GO TO 3.

[VQ37VHR]
A

EC

3.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Start engine and run it for 65 minutes at idle speed.
If COOLAN TEMP/S increases to more than 10C (50F) within 65 minutes, stop engine because
the test result will be OK.
CAUTION:
Be careful not to overheat engine.
2. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> EC-191, "Diagnosis Procedure"
NO
>> INSPECTION END

1.

Diagnosis Procedure

INFOID:0000000001734023

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to EC-191, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Replace engine coolant temperature sensor.

3.CHECK THERMOSTAT OPERATION

When the engine is cold [lower than 70C (158F)] condition, grasp lower radiator hose and confirm the engine
coolant does not flow.
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair or replace thermostat. Refer to CO-22, "Removal and Installation".

4.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

P

Component Inspection

INFOID:0000000001910833

1.CHECK ENGINE COOLANT TEMPERATURE SENSOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect engine coolant temperature sensor harness connector.
Remove engine coolant temperature sensor.

Revision: 2007 June

EC-191

G37 Coupe

P0125 ECT SENSOR

< COMPONENT DIAGNOSIS >
4. Check resistance between engine coolant temperature sensor
terminals by heating with hot water as shown in the figure.
Terminals

1 and 2

Condition

Temperature C (F)

Resistance
20 (68)

2.37 - 2.63 k

50 (122)

0.68 - 1.00 k

90 (194)

0.236 - 0.260 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace engine coolant temperature sensor.

Revision: 2007 June

[VQ37VHR]

EC-192

JMBIA0080ZZ

G37 Coupe

P0127 IAT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0127 IAT SENSOR

Description

INFOID:0000000001910830

The intake air temperature sensor is built-into mass air flow sensor
(1). The sensor detects intake air temperature and transmits a signal
to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.
NOTE:
ECM uses only the intake air temperature sensor (bank 1) for engine
control and self-diagnosis. It does not use the intake air temperature
sensor (bank 2).

EC

PBIA9559J

<Reference data>
F
Intake air temperature
C (F)

Voltage*

Resistance k

25 (77)

3.3

1.800 - 2.200

80 (176)

1.2

0.283 - 0.359

*: These data are reference values and are measured between ECM terminal 67
(Intake air temperature sensor) and ground.

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing
so may result in damage to the ECMs transistor. Use a ground other than ECM
terminals, such as the ground.

DTC Logic

SEF012P

I
INFOID:0000000001734026

DTC DETECTION LOGIC

DTC No.
P0127

Trouble diagnosis name

Intake air temperature
too high

DTC detecting condition

Rationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage signal
from engine coolant temperature sensor.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted)
Intake air temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road
test is expected to be easier, it is unnecessary to lift the vehicle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
-

With CONSULT-III
Wait until engine coolant temperature is less than 90C (194F)
Turn ignition switch ON.
Select DATA MONITOR mode with CONSULT-III.

Revision: 2007 June

EC-193

G37 Coupe

P0127 IAT SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
Check the engine coolant temperature.
If the engine coolant temperature is not less than 90C (194F), turn ignition switch OFF and cool down
engine.
NOTE:
Perform the following steps before engine coolant temperature is above 90C (194F).
2. Turn ignition switch ON.
3. Select DATA MONITOR mode with CONSULT-III.
4. Start engine.
5. Hold vehicle speed at more than 70 km/h (43 MPH) for 100 consecutive seconds.
CAUTION:
Always drive vehicle at a safe speed.
6. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-194, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734027

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK INTAKE AIR TEMPERATURE SENSOR

Refer to EC-194, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Replace mass air flow sensor (bank 1) (with intake air temperature sensor).

3.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910831

1.CHECK INTAKE AIR TEMPERATURE SENSOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect mass air flow sensor (bank 1) harness connector.
Check resistance between mass air flow sensor (bank 1) terminals as follows.
Terminals
1 and 2

Condition
Temperature C (F)

Resistance
25 (77)

1.800 - 2.200 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace mass air flow sensor (with intake air temperature sensor) (bank 1).

Revision: 2007 June

EC-194

G37 Coupe

P0128 THERMOSTAT FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0128 THERMOSTAT FUNCTION

DTC Logic

INFOID:0000000001734029

DTC DETECTION LOGIC

EC

Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long
enough.
This is due to a leak in the seal or the thermostat stuck open.
DTC No.

P0128

Trouble diagnosis name

Thermostat function

DTC detecting condition

Possible cause

The engine coolant temperature does not reach

to specified temperature even though the engine has run long enough.

Thermostat
Leakage from sealing portion of thermostat
Engine coolant temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
For best results, perform at ambient temperature of 10C (14F) or higher.
For best results, perform at engine coolant temperature of 10C (14F) to 60C (140F).
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Replace thermostat with new one. Refer to CO-22, "Removal and Installation". Use only a genuine NISSAN thermostat as a replacement. If an incorrect thermostat is used, the MIL may come on.
2. Turn ignition switch ON.
3. Select COOLAN TEMP/S in DATA MONITOR mode with CONSULT-III.
4. Check the indication of COOLAN TEMP/S.
If it is below 60C (140F), go to the following steps.
If it is above 60C (140F), cool engine down to less than 60C (140F). Then go to next step.
5. Drive vehicle for 10 consecutive minutes under the following conditions.
1.

VHCL SPEED SE

80 - 120 km/h (50 - 75 mph)

INFOID:0000000001734030

Refer to EC-196, "Component Inspection".

Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace engine coolant temperature sensor.

EC-195

1.CHECK ENGINE COOLANT TEMPERATURE SENSOR

Revision: 2007 June

CAUTION:
Always drive vehicle at a safe speed.
6. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-195, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

G37 Coupe

P0128 THERMOSTAT FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Component Inspection

INFOID:0000000001910834

1.CHECK ENGINE COOLANT TEMPERATURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect engine coolant temperature sensor harness connector.
Remove engine coolant temperature sensor.
Check resistance between engine coolant temperature sensor
terminals by heating with hot water as shown in the figure.

Terminals

1 and 2

Condition

Temperature C (F)

Resistance
20 (68)

2.37 - 2.63 k

50 (122)

0.68 - 1.00 k

90 (194)

0.236 - 0.260 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace engine coolant temperature sensor.

Revision: 2007 June

EC-196

JMBIA0080ZZ

G37 Coupe

P0130, P0150 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0130, P0150 A/F SENSOR 1

Description

INFOID:0000000001734032

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sensor. The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocarbon density in rich.

EC

JMBIA0112GB

Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800C
(1,472F).

H
PBIB3354E

DTC Logic

INFOID:0000000001734033

DTC DETECTION LOGIC

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal fluctuates according to fuel feedback control.
DTC No.

P0130

P0150

Trouble diagnosis name

Air fuel ratio (A/F) sensor 1

(bank 1) circuit

Air fuel ratio (A/F) sensor 1

(bank 2) circuit

DTC detecting condition

A)

The A/F signal computed by ECM from the A/F

sensor 1 signal is constantly in the range other
than approx. 2.2V.

B)

The A/F signal computed by ECM from the A/F

sensor 1 signal is constantly approx. 2.2V.

A)

The A/F signal computed by ECM from the A/F

sensor 1 signal is constantly in the range other
than approx. 2.2V.

B)

The A/F signal computed by ECM from the A/F

sensor 1 signal is constantly approx. 2.2V.

Possible Cause

L
Harness or connectors
(The A/F sensor 1 circuit is open
or shorted.)
A/F sensor 1

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
>> GO TO 2.
Revision: 2007 June

EC-197

G37 Coupe

P0130, P0150 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

1. Start engine and warm it up to normal operating temperature.
2. Let it idle for 2 minutes.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-199, "Diagnosis Procedure".
NO-1 >> With CONSULT-III: GO TO 3.
NO-2 >> Without CONSULT-III: GO TO 7.

3.CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION

1. Start engine and warm it up to normal operating temperature.
2. Select A/F SEN1 (B1) or A/F SEN1 (B2) in DATA MONITOR mode with CONSULT-III.
3. Check A/F SEN1 (B1) or A/F SEN1 (B2) indication.
Does the indication fluctuates around 2.2V?
YES >> GO TO 4.
NO
>> Go to EC-199, "Diagnosis Procedure".

4.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B-I

1.
2.
3.

Select A/F SEN1 (B1) P1276 (for DTC P0130) or A/F SEN1 (B2) P1286 (for DTC P0150) of A/F
SEN1 in DTC WORK SUPPORT mode with CONSULT-III.
Touch START.
When the following conditions are met, TESTING will be displayed on the CONSULT-III screen.

ENG SPEED

1,100 - 3,200 rpm

VHCL SPEED SE

More than 64 km/h (40 mph)

B/FUEL SCHDL

1.0 - 8.0 msec

Selector lever

D position (A/T)
5th position (M/T)

If TESTING is not displayed after 20 seconds, retry from step 2.

CAUTION:
Always drive vehicle at a safe speed.
Is TESTING displayed on CONSULT-III screen?
YES >> GO TO 5.
NO
>> Check A/F sensor 1 function again. GO TO 3.

5.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B-II

Release accelerator pedal fully.
NOTE:
Never apply brake during releasing the accelerator pedal.
Which does TESTING change to?
COMPLETED>>GO TO 6.
OUT OF CONDITION>>Retry DTC CONFIRMATION PROCEDURE. GO TO 4.

6.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B-III

Touch SELF-DIAG RESULT.
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-199, "Diagnosis Procedure".

7.PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B

Perform component function check. Refer to EC-199, "Component Function Check".
NOTE:
Use component function check to check the overall function of the A/F sensor 1 circuit. During this check, a
1st trip DTC might not be confirmed.
Is the inspection result normal?
Revision: 2007 June

EC-198

G37 Coupe

P0130, P0150 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> INSPECTION END
NO
>> Go to EC-199, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734034

1.PERFORM COMPONENT FUNCTION CHECK

EC

With GST
Start engine and warm it up to normal operating temperature.
Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in the suitable gear position.
Shift the selector lever to D position (A/T) or 5th position (M/T), then release the accelerator pedal fully
until the vehicle speed decreases to 50 km/h (30 MPH).
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
Never apply brake during releasing the accelerator pedal.
4. Repeat steps 2 to 3 for five times.
5. Stop the vehicle and turn ignition switch OFF.
6. Turn ignition switch ON.
7. Turn ignition switch OFF and wait at least 10 seconds.
8. Restart engine.
9. Repeat steps 2 to 3 for five times.
10. Stop the vehicle and connect GST to the vehicle.
11. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-199, "Diagnosis Procedure".
NO
>> INSPECTION END
1.
2.
3.

Diagnosis Procedure

INFOID:0000000001734035

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect A/F sensor 1 harness connector.

Turn ignition switch ON.
Check the voltage between A/F sensor 1 harness connector and ground.

M
DTC

A/F sensor 1
Bank

Connector

Terminal

P0130

F3

P0150

F20

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between A/F sensor 1 and fuse
>> Repair or replace harness or connectors.
Revision: 2007 June

EC-199

G37 Coupe

P0130, P0150 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

4.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

DTC

P0130

P0150

4.

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

Connector

Terminal

57

61

F102

F20

Continuity

65

Existed

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

DTC

P0130

P0150

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

F20

Connector

1
2
1

Terminal

Ground

Continuity

Ground

Not existed

57
F102

61
65
66

5. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK INTERMITTENT INCIDENT

Perform GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair or replace.

6.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

Revision: 2007 June

EC-200

G37 Coupe

P0131, P0151 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0131, P0151 A/F SENSOR 1

Description

INFOID:0000000001910853

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sensor. The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocarbon density in rich.

EC

JMBIA0112GB

Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800C
(1,472F).

H
PBIB3354E

DTC Logic

INFOID:0000000001734037

DTC DETECTION LOGIC

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal is not inordinately low.
DTC No.

Trouble diagnosis name

P0131

Air fuel ratio (A/F) sensor 1

(bank 1) circuit low voltage

P0151

Air fuel ratio (A/F) sensor 1

(bank 2) circuit low voltage

DTC detecting condition

Possible Cause

The A/F signal computed by ECM from the A/

F sensor 1 signal is constantly approx. 0V.

Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
A/F sensor 1

DTC CONFIRMATION PROCEDURE

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.

>> GO TO 2.

2.CHECK A/F SENSOR FUNCTION

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Select A/F SEN1 (B1) or A/F SEN1 (B2) in DATA MONITOR mode with CONSULT-III.
Check A/F SEN1 (B1) or A/F SEN1 (B2) indication.

Revision: 2007 June

1.PRECONDITIONING

1.
2.
3.

EC-201

G37 Coupe

P0131, P0151 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

With GST
Follow the procedure With CONSULT-III above.
Is the indication constantly approx. 0V?
YES >> Go to EC-202, "Diagnosis Procedure".
NO
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Restart engine.
Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine.
CAUTION:
Always drive vehicle at a safe speed.
6. Maintain the following conditions for about 20 consecutive seconds.
1.
2.
3.
4.
5.

ENG SPEED

1,000 - 3,200 rpm

VHCL SPEED SE

More than 40 km/h (25 mph)

B/FUEL SCHDL

1.5 - 9.0 msec

Selector lever

Suitable position

NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
If this procedure is not completed within 1 minute after restarting engine at step 1, return to step
1.
7. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-202, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734038

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect A/F sensor 1 harness connector.

Turn ignition switch ON.
Check the voltage between A/F sensor 1 harness connector and ground.

DTC

A/F sensor 1
Bank

Connector

Terminal

P0131

F3

P0151

F20

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Revision: 2007 June

EC-202

G37 Coupe

P0131, P0151 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Check the following.
Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between A/F sensor 1 and fuse

EC

>> Repair or replace harness or connectors.

4.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

DTC

P0131

P0151

4.

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

Connector

Terminal

Existed

57

61

F102

F20

Continuity

65

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

DTC

P0131

P0151

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

F20

Connector

1
2
1

Terminal

Ground

Continuity

Ground

Not existed

57
F102

61
65

66

5. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK INTERMITTENT INCIDENT

L

Perform GI-38, "Intermittent Incident".

Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair or replace.

6.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

Revision: 2007 June

EC-203

G37 Coupe

P0132, P0152 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0132, P0152 A/F SENSOR 1

Description

INFOID:0000000001910854

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sensor. The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocarbon density in rich.
JMBIA0112GB

Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800C
(1,472F).

PBIB3354E

DTC Logic

INFOID:0000000001734040

DTC DETECTION LOGIC

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal is not inordinately high.
DTC No.

Trouble diagnosis name

P0132

Air fuel ratio (A/F) sensor 1

(bank 1) circuit high voltage

P0152

Air fuel ratio (A/F) sensor 1

(bank 2) circuit high voltage

DTC detecting condition

Possible Cause

The A/F signal computed by ECM from the A/F

sensor 1 signal is constantly approx. 5V.

Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
A/F sensor 1

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
>> GO TO 2.

2.CHECK A/F SENSOR FUNCTION

1.
2.
3.

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Select A/F SEN1 (B1) or A/F SEN1 (B2) in DATA MONITOR mode with CONSULT-III.
Check A/F SEN1 (B1) or A/F SEN1 (B2) indication.

Revision: 2007 June

EC-204

G37 Coupe

P0132, P0152 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

With GST
Follow the procedure With CONSULT-III above.
Is the indication constantly approx. 5V?
YES >> Go to EC-205, "Diagnosis Procedure".
NO
>> GO TO 3.

EC

3.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Restart engine.
Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine.
CAUTION:
Always drive vehicle at a safe speed.
6. Maintain the following conditions for about 20 consecutive seconds.
1.
2.
3.
4.
5.

ENG SPEED

1,000 - 3,200 rpm

VHCL SPEED SE

More than 40 km/h (25 mph)

B/FUEL SCHDL

1.5 - 9.0 msec

Selector lever

Suitable position

NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
If this procedure is not completed within 1 minute after restarting engine at step 1, return to step
1.
7. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC is detected?
YES >> Go to EC-205, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734041

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect A/F sensor 1 harness connector.

Turn ignition switch ON.
Check the voltage between A/F sensor 1 harness connector and ground.

O
DTC

A/F sensor 1
Bank

Connector

Terminal

P0132

F3

P0152

F20

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Revision: 2007 June

EC-205

G37 Coupe

P0132, P0152 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Check the following.
Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between A/F sensor 1 and fuse
>> Repair or replace harness or connectors.

4.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

DTC

P0132

P0152

4.

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

Connector

Terminal

57

61

F102

F20

Continuity

65

Existed

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

DTC

P0132

P0152

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

F20

Connector

1
2
1

Terminal

Ground

Continuity

Ground

Not existed

57
F102

61
65
66

5. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK INTERMITTENT INCIDENT

Perform GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair or replace.

6.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

Revision: 2007 June

EC-206

G37 Coupe

P0133, P0153 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0133, P0153 A/F SENSOR 1

Description

INFOID:0000000001910855

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sensor. The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocarbon density in rich.

EC

JMBIA0112GB

Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800C
(1,472F).

H
PBIB3354E

DTC Logic

INFOID:0000000001734043

DTC DETECTION LOGIC

To judge the malfunction of A/F sensor 1, this diagnosis measures response time of the A/F signal computed
by ECM from the A/F sensor 1 signal. The time is compensated by engine operating (speed and load), fuel
feedback control constant, and the A/F sensor 1 temperature index. Judgment is based on whether the compensated time (the A/F signal cycling time index) is inordinately long or not.
DTC No.
P0133

P0153

Trouble diagnosis name

DTC detecting condition

Possible Cause

The response of the A/F signal computed by

ECM from A/F sensor 1 signal takes more than
the specified time.

Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
A/F sensor 1
A/F sensor 1 heater
Fuel pressure
Fuel injector
Intake air leaks
Exhaust gas leaks
PCV
Mass air flow sensor

Air fuel ratio (A/F) sensor 1

(bank 1) circuit slow response

Air fuel ratio (A/F) sensor 1

(bank 2) circuit slow response

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Do you have CONSULT-III?
Revision: 2007 June

EC-207

G37 Coupe

P0133, P0153 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 2.
NO
>> GO TO 5.

2.PERFORM DTC CONFIRMATION PROCEDURE-I

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1minute under no load.
Let engine idle for 1 minute.
Select A/F SEN1(B1) P1278/P1279 (for DTC P0133) or A/F SEN1(B2) P1288/P1289 (for DTC P0153)
of A/F SEN1 in DTC WORK SUPPORT mode with CONSULT-III.
8. Touch START.
Is COMPLETED displayed on CONSULT-III screen?
YES >> GO TO 3
NO
>> GO TO 4.
1.
2.
3.
4.
5.
6.
7.

3.PERFORM DTC CONFIRMATION PROCEDURE-II

Touch SELF-DIAG RESULT.
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-209, "Diagnosis Procedure".

4.PERFORM DTC CONFIRMATION PROCEDURE-II

1. After perform the following procedure, TESTING will be displayed on the CONSULT-III screen.
Increase the engine speed up to about 3,600 rpm and keep it for 10 seconds.
Fully release accelerator pedal and then let engine idle for about 10 seconds.
If TESTING is not displayed after 10 seconds, refer to EC-132, "Component Function Check".
2. Wait for about 20 seconds at idle at under the condition that TESTING is displayed on the CONSULT-III
screen.
3. Make sure that TESTING changes to COMPLETED.
If TESTING changed to OUT OF CONDITION, refer to EC-132, "Component Function Check".
4. Touch SELF-DIAG RESULT.
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-209, "Diagnosis Procedure".

5.CHECK AIR-FUEL RATIO SELF-LEARNING VALUE

With GST
1. Start engine and warm it up to normal operating temperature.
2. Select Service $01 with GST.
3. Calculate the total value of Short term fuel trim and Long term fuel trim indications.
Is the total percentage within 15%?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Intake air leaks
Exhaust gas leaks
Incorrect fuel pressure
Lack of fuel
Fuel injector
Incorrect PCV hose connection
PCV valve
Mass air flow sensor

Revision: 2007 June

EC-208

G37 Coupe

P0133, P0153 A/F SENSOR 1

< COMPONENT DIAGNOSIS >
>> Repair or replace malfunctioning part.

[VQ37VHR]

7.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.
EC
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1minute under no load.
5. Let engine idle for 1 minute.
6. Increase the engine speed up to about 3,600 rpm and keep it for 10 seconds.
C
7. Fully release accelerator pedal and then let engine idle for about 1 minute.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
D
YES >> Go to EC-209, "Diagnosis Procedure".
NO
>> INSPECTION END
E
Diagnosis Procedure
INFOID:0000000001734044

1.CHECK GROUND CONNECTION

F

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.RETIGHTEN A/F SENSOR 1

Loosen and retighten the A/F sensor 1. Refer to EM-33, "Removal and Installation".
I

>> GO TO 3.

3.CHECK EXHAUST GAS LEAK

1.
2.

Start engine and run it at idle.

Listen for an exhaust gas leak before three way catalyst 1.

M
PBIB1922E

Is exhaust gas leak detected?

YES >> Repair or replace.
NO
>> GO TO 4.

4.CHECK FOR INTAKE AIR LEAK

O

Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES >> Repair or replace.
NO
>> GO TO 5.

5.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P172, P0174 or P0175 detected? Is it difficult to start engine?

Revision: 2007 June

EC-209

G37 Coupe

P0133, P0153 A/F SENSOR 1

[VQ37VHR]
< COMPONENT DIAGNOSIS >
YES >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-232, "DTC Logic"
or EC-236, "DTC Logic".
NO
>> GO TO 6.

6.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect A/F sensor 1 harness connector.

Turn ignition switch ON.
Check the voltage between A/F sensor 1 harness connector and ground.

DTC

A/F sensor 1
Bank

Connector

Terminal

P0133

F3

P0153

F20

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 7.

7.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between A/F sensor 1 and fuse
>> Repair or replace harness or connectors.

8.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

DTC

P0133

P0153

4.

A/F sensor 1
Bank

Connector

F3

F20

ECM
Terminal

Connector

Terminal

1
2
1

Continuity

57
61

F102

65

Existed

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

DTC

P0133

P0153

A/F sensor 1
Bank

Connector

F3

F20

ECM
Terminal

Connector

1
2
1

Terminal

Ground

Continuity

Ground

Not existed

57
F102

61
65
66

5. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER

Refer to EC-157, "Component Inspection".
Revision: 2007 June

EC-210

G37 Coupe

P0133, P0153 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 13.

10.CHECK MASS AIR FLOW SENSOR

EC

Check both mass air flow sensor (bank 1 and bank 2).
Refer to EC-169, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 11.
NO
>> Replace malfunctioning mass air flow sensor.

11.CHECK PCV VALVE

Refer to EC-509, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 12.
NO
>> Repair or replace PCV valve.

12.CHECK INTERMITTENT INCIDENT

Perform GI-38, "Intermittent Incident".

Is the inspection result normal?
YES >> GO TO 13.
NO
>> Repair or replace.

13.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

K

Revision: 2007 June

EC-211

G37 Coupe

P0137, P0157 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0137, P0157 HO2S2

Description

INFOID:0000000001734045

The heated oxygen sensor 2, after three way catalyst 1, monitors the
oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the signal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
SEF327R

DTC Logic

INFOID:0000000001734046

DTC DETECTION LOGIC

The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer
switching time. To judge the malfunctions of heated oxygen sensor
2, ECM monitors whether the maximum voltage of the sensor is sufficiently high during the various driving condition such as fuel-cut.

SEF259VA

DTC No.
P0137

P0157

Trouble diagnosis name

Heated oxygen sensor 2
(bank 1) circuit low voltage
Heated oxygen sensor 2
(bank 2) circuit low voltage

DTC detecting condition

The maximum voltage from the sensor is not

reached to the specified voltage.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
Intake air leaks

DTC CONFIRMATION PROCEDURE

1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 5.

2.PRECONDITIONING
If DTC confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
For better results, perform DTC WORK SUPPORT at a temperature of 0 to 30 C (32 to 86 F).
>> GO TO 3.
Revision: 2007 June

EC-212

G37 Coupe

P0137, P0157 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

3.PERFORM DTC CONFIRMATION PROCEDURE

A
With CONSULT-III
1. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
EC
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load. C
7. Let engine idle for 1 minute.
8. Make sure that COOLAN TEMP/S indicates more than 70C (158F).
If not, warm up engine and go to next step when COOLAN TEMP/S indication reaches to 70C (158F). D
9. Open engine hood.
10. Select HO2S2 (B1) P1147 (for DTC P0137) or HO2S2 (B2) P1167 (for DTC P0157) of HO2S2 in
DTC WORK SUPPORT mode with CONSULT-III.
E
11. Start engine and following the instruction of CONSULT-III.
NOTE:
It will take at most 10 minutes until COMPLETED is displayed.
12. Touch SELF-DIAG RESULTS.
F
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-214, "Diagnosis Procedure".
G
CAN NOT BE DIAGNOSED>>GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE AGAIN

1.
2.

Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
Perform DTC confirmation procedure again.

>> GO TO 3.

5.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-213, "Component Function Check".
NOTE:
Use component function check to check the overall function of the heated oxygen sensor 2 circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-214, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734047

1.PERFORM COMPONENT FUNCTION CHECK-I

1.
2.
3.
4.
5.
6.
7.

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Check the voltage between ECM harness connector and ground under the following condition.

P
DTC
P0137
P0157

ECM
Connector
F102

Terminal
76
80

Ground

Condition

Ground

Revving up to 4,000 rpm under no load at

least 10 times

Voltage
The voltage should be above 0.68V at
least once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
Revision: 2007 June

EC-213

G37 Coupe

P0137, P0157 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> GO TO 2.

2.PERFORM COMPONENT FUNCTION CHECK-II

Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0137
P0157

ECM
Connector

Terminal
76

F102

80

Ground

Ground

Condition

Voltage

Keeping engine at idle for 10 minutes

The voltage should be above 0.68V at

least once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 3.

3.PERFORM COMPONENT FUNCTION CHECK-III

Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0137
P0157

ECM
Connector

Terminal
76

F102

80

Ground

Condition

Voltage

Ground

Coasting from 80 km/h (50 MPH) in D position (A/T), 4th gear position (M/T)

The voltage should be above 0.68V at

least once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-214, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734048

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0174 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0171 or P0174. Refer to EC-232, "DTC Logic".
NO
>> GO TO 3.

3.CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect heated oxygen sensor 2 harness connector.
Disconnect ECM harness connector.
Check the continuity between HO2S2 harness connector and ECM harness connector.

DTC

HO2S2

ECM

Bank

Connector

Terminal

P0137

F54

P0157

F53

Connector

Terminal

F102

84

Continuity

Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
Revision: 2007 June

EC-214

G37 Coupe

P0137, P0157 HO2S2

< COMPONENT DIAGNOSIS >
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]
A

4.CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between HO2S2 harness connector and ECM harness connector.

DTC

2.

HO2S2

ECM

Bank

Connector

Terminal

P0137

F54

P0157

F53

Connector

Terminal
76

F102

80

EC

Continuity

C
Existed

Check the continuity between HO2S2 harness connector or ECM harness connector and ground.

DTC

HO2S2
Bank

Connector

ECM
Terminal

P0137

F54

P0157

F53

Connector
F102

Terminal
76
80

Ground

Continuity

Ground

Not existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK HEATED OXYGEN SENSOR 2

Refer to EC-215, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734049

1.INSPECTION START

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.CHECK HEATED OXYGEN SENSOR 2

1.
2.

With CONSULT-III
Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
Start engine and warm it up to the normal operating temperature.

Revision: 2007 June

EC-215

G37 Coupe

P0137, P0157 HO2S2

[VQ37VHR]
< COMPONENT DIAGNOSIS >
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Select FUEL INJECTION in ACTIVE TEST mode, and select HO2S2 (B1)/(B2) as the monitor item
with CONSULT-III.
7. Check HO2S2 (B1)/(B2) at idle speed when adjusting FUEL INJECTION to 25%.

PBIB3458E

HO2S2 (B1)/(B2) should be above 0.68V at least once when the FUEL INJECTION is +25%.
HO2S2 (B1)/(B2) should be below 0.18V at least once when the FUEL INJECTION is 25%.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> GO TO 6.

3.CHECK HEATED OXYGEN SENSOR 2-I

1.
2.
3.
4.
5.

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Check the voltage between ECM harness connector and ground under the following condition.
ECM

Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Condition

Voltage

Ground

Revving up to 4,000 rpm under no load at

least 10 times

The voltage should be above 0.68V at

least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 4.

4.CHECK HEATED OXYGEN SENSOR 2-II

Check the voltage between ECM harness connector and ground under the following condition.
ECM
Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Ground

Condition

Keeping engine at idle for 10 minutes

Voltage
The voltage should be above 0.68V at
least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 5.

5.CHECK HEATED OXYGEN SENSOR 2-III

Check the voltage between ECM harness connector and ground under the following condition.

Revision: 2007 June

EC-216

G37 Coupe

P0137, P0157 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

A
Ground

Condition

Voltage

Ground

Coasting from 80 km/h (50 MPH) in D position (A/T), 4th gear position (M/T)

The voltage should be above 0.68V at

least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 6.

6.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

Revision: 2007 June

EC-217

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0138, P0158 HO2S2

Description

INFOID:0000000001910856

The heated oxygen sensor 2, after three way catalyst 1, monitors the
oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the signal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
SEF327R

DTC Logic

INFOID:0000000001734051

DTC DETECTION LOGIC

The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/
F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer switching time.
MALFUNCTION A
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the voltage is unusually high during the various driving condition such as fuel-cut.

PBIB1848E

MALFUNCTION B
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the minimum voltage of sensor is sufficiently low during the
various driving condition such as fuel-cut.

PBIB2376E

DTC No.

Trouble diagnosis name

DTC detecting condition

A)

P0138

Heated oxygen sensor 2

(bank 1) circuit high voltage

Revision: 2007 June

B)

Possible cause

An excessively high voltage from the sensor is sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2

The minimum voltage from the sensor is

not reached to the specified voltage.

Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector

EC-218

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC No.

Trouble diagnosis name

DTC detecting condition

A)

P0158

Heated oxygen sensor 2

(bank 2) circuit high voltage

B)

Possible cause

An excessively high voltage from the sensor is sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2

The minimum voltage from the sensor is

not reached to the specified voltage.

Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector

EC

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

1. Start engine and warm it up to the normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-221, "Diagnosis Procedure".
NO-1 >> With CONSULT-III: GO TO 3.
NO-2 >> Without CONSULT-III: GO TO 5.

3.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B

NOTE:
For better results, perform DTC WORK SUPPORT at a temperature of 0 to 30 C (32 to 86 F).
1. Select DATA MONITOR mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
7. Let engine idle for 1 minute.
8. Make sure that COOLAN TEMP/S indicates more than 70C (158F).
If not, warm up engine and go to next step when COOLAN TEMP/S indication reaches to 70C (158F).
9. Open engine hood.
10. Select HO2S2 (B1) P1146 (for DTC P0138) or HO2S2 (B2) P1166 (for DTC P0158) of HO2S2 in
DTC WORK SUPPORT mode with CONSULT-III.
11. Start engine and following the instruction of CONSULT-III.
NOTE:
It will take at most 10 minutes until COMPLETED is displayed.
12. Touch SELF-DIAG RESULTS.
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-221, "Diagnosis Procedure".
CON NOT BE DIAGNOSED>>GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B AGAIN

1.
2.

Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
Perform DTC confirmation procedure again.

Revision: 2007 June

EC-219

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> GO TO 3.

5.PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B

Perform component function check. Refer to EC-220, "Component Function Check".
NOTE:
Use component function check to check the overall function of the heated oxygen sensor 2 circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-221, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734052

1.PERFORM COMPONENT FUNCTION CHECK-I

1.
2.
3.
4.
5.
6.
7.

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0138
P0158

ECM
Connector

Terminal
76

F102

80

Ground

Condition

Voltage

Ground

Revving up to 4,000 rpm under no load at

least 10 times

The voltage should be below 0.18V at least

once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.PERFORM COMPONENT FUNCTION CHECK-II

Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0138
P0158

ECM
Connector

Terminal
76

F102

80

Ground

Ground

Condition

Keeping engine at idle for 10 minutes

Voltage
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 3.

3.PERFORM COMPONENT FUNCTION CHECK-III

Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0138
P0158

ECM
Connector
F102

Terminal
76
80

Ground

Condition

Voltage

Ground

Coasting from 80 km/h (50 MPH) in D position (A/T), 4th gear position (M/T)

The voltage should be below 0.18V at least

once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-221, "Diagnosis Procedure".
Revision: 2007 June

EC-220

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001734053

1.INSPECTION START
Confirm the detected malfunction (A or B). Refer to EC-218, "DTC Logic".
Which malfunction is detected?
A
>> GO TO 2
B
>> GO TO 9.

EC

2.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace ground connection.

3.CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Disconnect heated oxygen sensor 2 harness connector.

Disconnect ECM harness connector.
Check the continuity between HO2S2 harness connector and ECM harness connector.

DTC

HO2S2

ECM

Bank

Connector

Terminal

P0138

F54

P0158

F53

Connector

Terminal

F102

84

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between HO2S2 harness connector and ECM harness connector.
K
DTC

2.

HO2S2

ECM

Bank

Connector

Terminal

P0138

F54

P0158

F53

Connector

Terminal
76

F102

80

Continuity

L
Existed

Check the continuity between HO2S2 harness connector or ECM harness connector and ground.

DTC

HO2S2

ECM

Bank

Connector

Terminal

P0138

F54

P0158

F53

Connector
F102

Terminal
76
80

Ground

Continuity

Ground

Not existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK HO2S2 CONNECTOR FOR WATER

Check connectors for water.
Water should not exist.
Is the inspection result normal?
Revision: 2007 June

EC-221

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 6.
NO
>> Repair or replace harness or connectors.

6.CHECK HEATED OXYGEN SENSOR 2

Refer to EC-223, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> GO TO 7.

7.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

9.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Repair or replace ground connection.

10.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 or P0175 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0172, P0175. Refer to EC-236, "DTC Logic".
NO
>> GO TO 11.

11.CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect heated oxygen sensor 2 harness connector.
Disconnect ECM harness connector.
Check the continuity between HO2S2 harness connector and ECM harness connector.

DTC

HO2S2

ECM

Bank

Connector

Terminal

P0138

F54

P0158

F53

Connector

Terminal

F102

84

Continuity

Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 12.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

12.CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between HO2S2 harness connector and ECM harness connector.

Revision: 2007 June

EC-222

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

2.

HO2S2

ECM

Bank

Connector

Terminal

P0138

F54

P0158

F53

Connector

Terminal
76

F102

80

Continuity

EC

Existed

Check the continuity between HO2S2 harness connector or ECM harness connector and ground.
C
DTC

HO2S2

ECM

Bank

Connector

Terminal

P0138

F54

P0158

F53

Connector
F102

Terminal
76
80

Ground

Continuity

D
Ground

Not existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 13.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

13.CHECK HEATED OXYGEN SENSOR 2

Refer to EC-223, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> GO TO 14.

14.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

15.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001910858

1.INSPECTION START
N

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.CHECK HEATED OXYGEN SENSOR 2

1.
2.
3.
4.
5.
6.

With CONSULT-III
Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Select FUEL INJECTION in ACTIVE TEST mode, and select HO2S2 (B1)/(B2) as the monitor item
with CONSULT-III.

Revision: 2007 June

EC-223

G37 Coupe

P0138, P0158 HO2S2

< COMPONENT DIAGNOSIS >
7. Check HO2S2 (B1)/(B2) at idle speed when adjusting FUEL INJECTION to 25%.

[VQ37VHR]

PBIB3458E

HO2S2 (B1)/(B2) should be above 0.68V at least once when the FUEL INJECTION is +25%.
HO2S2 (B1)/(B2) should be below 0.18V at least once when the FUEL INJECTION is 25%.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> GO TO 6.

3.CHECK HEATED OXYGEN SENSOR 2-I

1.
2.
3.
4.
5.

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Check the voltage between ECM harness connector and ground under the following condition.
ECM

Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Condition

Voltage

Ground

Revving up to 4,000 rpm under no load at

least 10 times

The voltage should be above 0.68V at

least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 4.

4.CHECK HEATED OXYGEN SENSOR 2-II

Check the voltage between ECM harness connector and ground under the following condition.
ECM
Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Ground

Condition

Keeping engine at idle for 10 minutes

Voltage
The voltage should be above 0.68V at
least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 5.

5.CHECK HEATED OXYGEN SENSOR 2-III

Check the voltage between ECM harness connector and ground under the following condition.

Revision: 2007 June

EC-224

G37 Coupe

P0138, P0158 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

A
Ground

Condition

Voltage

Ground

Coasting from 80 km/h (50 MPH) in D position (A/T), 4th gear position (M/T)

The voltage should be above 0.68V at

least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 6.

6.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

Revision: 2007 June

EC-225

G37 Coupe

P0139, P0159 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0139, P0159 HO2S2

Description

INFOID:0000000001910857

The heated oxygen sensor 2, after three way catalyst 1, monitors the
oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the signal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
SEF327R

DTC Logic

INFOID:0000000001734056

DTC DETECTION LOGIC

The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer
switching time. To judge the malfunctions of heated oxygen sensor
2, ECM monitors whether the switching response of the sensor's
voltage is faster than specified during the various driving condition
such as fuel-cut.

SEF302U

DTC No.
P0139

P0159

Trouble diagnosis name

Heated oxygen sensor 2
(bank 1) circuit slow response
Heated oxygen sensor 2
(bank 2) circuit slow response

DTC detecting condition

It takes more time for the sensor to respond between rich and lean than the specified time.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
Intake air leaks

DTC CONFIRMATION PROCEDURE

1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 5.

2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
For better results, perform DTC WORK SUPPORT at a temperature of 0 to 30 C (32 to 86 F).
>> GO TO 3.
Revision: 2007 June

EC-226

G37 Coupe

P0139, P0159 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

3.PERFORM DTC CONFIRMATION PROCEDURE

A
With CONSULT-III
1. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
EC
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load. C
7. Let engine idle for 1 minute.
8. Make sure that COOLAN TEMP/S indicates more than 70C (158F).
If not, warm up engine and go to next step when COOLAN TEMP/S indication reaches to 70C (158F). D
9. Open engine hood.
10. Select HO2S2 (B1) P0139 or HO2S2 (B2) P0159 of HO2S2 in DTC WORK SUPPORT mode with
CONSULT-III.
E
11. Start engine and following the instruction of CONSULT-III.
NOTE:
It will take at most 10 minutes until COMPLETED is displayed.
12. Touch SELF-DIAG RESULTS.
F
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-228, "Diagnosis Procedure".
G
CAN NOT BE DIAGNOSED>>GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE AGAIN

1.
2.

Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
Perform DTC confirmation procedure again.

>> GO TO 3.

5.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-227, "Component Function Check".
NOTE:
Use component function check to check the overall function of the heated oxygen sensor 2 circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-228, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734057

1.PERFORM COMPONENT FUNCTION CHECK-I

1.
2.
3.
4.
5.
6.
7.

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Check the voltage between ECM harness connector and ground under the following condition.

P
DTC
P0139
P0159

ECM
Connector
F102

Terminal
76
80

Ground

Condition

Voltage

Ground

Revving up to 4,000 rpm under no load at

least 10 times

A change of voltage should be more than

0.24V for 1 second during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
Revision: 2007 June

EC-227

G37 Coupe

P0139, P0159 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> GO TO 2.

2.PERFORM COMPONENT FUNCTION CHECK-II

Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0139
P0159

ECM
Connector

Terminal
76

F102

80

Ground

Ground

Condition

Voltage

Keeping engine at idle for 10 minutes

A change of voltage should be more than

0.24V for 1 second during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 3.

3.PERFORM COMPONENT FUNCTION CHECK-III

Check the voltage between ECM harness connector and ground under the following condition.

DTC
P0139
P0159

ECM
Connector

Terminal
76

F102

80

Ground

Condition

Voltage

Ground

Coasting from 80 km/h (50 MPH) in D position (A/T), 4th gear position (M/T)

A change of voltage should be more than

0.24V for 1 second during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-228, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734058

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-232, "DTC Logic"
or EC-236, "DTC Logic".
NO
>> GO TO 3.

3.CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect heated oxygen sensor 2 harness connector.
Disconnect ECM harness connector.
Check the continuity between HO2S2 harness connector and ECM harness connector.

DTC

5.

HO2S2

ECM

Bank

Connector

Terminal

P0139

F54

P0159

F53

Connector

Terminal

F102

84

Continuity

Existed

Also check harness for short to ground and short to power.

Revision: 2007 June

EC-228

G37 Coupe

P0139, P0159 HO2S2

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]
A

4.CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

DTC

2.

EC

Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2

ECM

Bank

Connector

Terminal

P0139

F54

P0159

F53

Connector

Terminal
76

F102

80

Continuity

Existed

Check the continuity between HO2S2 harness connector or ECM harness connector and ground.
E
DTC

HO2S2

ECM

Bank

Connector

Terminal

P0139

F54

P0159

F53

Connector
F102

Terminal
76
80

Ground

Continuity

Ground

Not existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK HEATED OXYGEN SENSOR 2

Refer to EC-229, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.

CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

M

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001910859

1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.CHECK HEATED OXYGEN SENSOR 2

1.

With CONSULT-III
Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.

Revision: 2007 June

EC-229

G37 Coupe

P0139, P0159 HO2S2

[VQ37VHR]
< COMPONENT DIAGNOSIS >
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Select FUEL INJECTION in ACTIVE TEST mode, and select HO2S2 (B1)/(B2) as the monitor item
with CONSULT-III.
7. Check HO2S2 (B1)/(B2) at idle speed when adjusting FUEL INJECTION to 25%.

PBIB3458E

HO2S2 (B1)/(B2) should be above 0.68V at least once when the FUEL INJECTION is +25%.
HO2S2 (B1)/(B2) should be below 0.18V at least once when the FUEL INJECTION is 25%.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> GO TO 6.

3.CHECK HEATED OXYGEN SENSOR 2-I

1.
2.
3.
4.
5.

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Check the voltage between ECM harness connector and ground under the following condition.
ECM

Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Condition

Voltage

Ground

Revving up to 4,000 rpm under no load at

least 10 times

The voltage should be above 0.68V at

least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 4.

4.CHECK HEATED OXYGEN SENSOR 2-II

Check the voltage between ECM harness connector and ground under the following condition.
ECM
Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Ground

Condition

Keeping engine at idle for 10 minutes

Voltage
The voltage should be above 0.68V at
least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 5.

5.CHECK HEATED OXYGEN SENSOR 2-III

Check the voltage between ECM harness connector and ground under the following condition.
Revision: 2007 June

EC-230

G37 Coupe

P0139, P0159 HO2S2

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

F102

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

A
Ground

Condition

Voltage

Ground

Coasting from 80 km/h (50 MPH) in D position (A/T), 4th gear position (M/T)

The voltage should be above 0.68V at

least once during this procedure.
The voltage should be below 0.18V at least
once during this procedure.

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 6.

6.REPLACE HEATED OXYGEN SENSOR 2

Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> INSPECTION END

Revision: 2007 June

EC-231

G37 Coupe

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

DTC Logic

INFOID:0000000001734060

DTC DETECTION LOGIC

With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the A/F sensors 1. The ECM calculates the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
Sensor

Density of oxygen in exhaust gas

(Mixture ratio feedback signal)

A/F sensor 1

DTC No.
P0171

P0174

Input signal to ECM

Trouble diagnosis name

ECM function
Fuel injection control

DTC detecting condition

Fuel injection system too

lean (bank 1)

Fuel injection system too

lean (bank 2)

Fuel injection system does not operate properly.

The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.)

Actuator
Fuel injector

Possible cause

Intake air leaks

A/F sensor 1
Fuel injector
Exhaust gas leaks
Incorrect fuel pressure
Lack of fuel
Mass air flow sensor
Incorrect PCV hose connection

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Start engine.
Is it difficult to start engine?
YES >> GO TO 3.
NO
>> GO TO 4.

3.RESTART ENGINE
If it is difficult to start engine, the fuel injection system has a malfunction, too.
Crank engine while depressing accelerator pedal.
Does engine start?
YES >> Go to EC-233, "Diagnosis Procedure".
NO
>> Check exhaust and intake air leak visually.

4.PERFORM DTC CONFIRMATION PROCEDURE-II

1. Keep engine idle for at least 10 minutes.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-233, "Diagnosis Procedure".
NO
>> GO TO 5.
Revision: 2007 June

EC-232

G37 Coupe

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

5.PERFORM DTC CONFIRMATION PROCEDURE-III

1.
2.
3.
4.

A
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
EC
Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 minutes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con- C
ditions should be satisfied at the same time.
Engine speed

Engine speed in the freeze frame data 400 rpm

Vehicle speed

Vehicle speed in the freeze frame data 10 km/h (6 MPH)

Engine coolant temperature (T) condition

When the freeze frame data shows lower than 70 C (158 F),
T should be lower than 70 C (158 F).

When the freeze frame data shows higher than or equal to 70 C (158 F),
T should be higher than or equal to 70 C (158 F).

5. Check 1st trip DTC.

Is 1st trip DTC detected?
YES >> Go to EC-233, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

G
INFOID:0000000001734061

1.CHECK EXHAUST GAS LEAK

1.
2.

Start engine and run it at idle.

Listen for an exhaust gas leak before three way catalyst 1.

PBIB1922E

Is exhaust gas leak detected?

YES >> Repair or replace.
NO
>> GO TO 2.

2.CHECK FOR INTAKE AIR LEAK

1. Listen for an intake air leak after the mass air flow sensor.
2. Check PCV hose connection.
Is intake air leak detected?
YES >> Repair or replace.
NO
>> GO TO 3.

3.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect corresponding A/F sensor 1 harness connector.
Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

Revision: 2007 June

EC-233

G37 Coupe

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

P0171

P0174

5.

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

Connector

Terminal

57

61

F102

F20

Continuity

65

Existed

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

DTC

P0171

P0174

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

F20

Connector

1
2
1

Terminal

Ground

Continuity

Ground

Not existed

57
F102

61
65
66

6. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK FUEL PRESSURE

1.
2.

Release fuel pressure to zero. Refer to EC-601, "Inspection".

Install fuel pressure gauge and check fuel pressure. Refer to EC-601, "Inspection".
At idling: Approximately 350 kPa (3.57 kg/cm2, 51 psi)

Is the inspection result normal?

YES >> GO TO 6.
NO
>> GO TO 5.

5. DETECT MALFUNCTIONING PART

Check fuel hoses and fuel tubes for clogging.
Is the inspection result normal?
YES >> Replace fuel filter and fuel pump assembly.
NO
>> Repair or replace.

6.CHECK MASS AIR FLOW SENSOR

With CONSULT-III
Install all removed parts.
Check MASS AIR FLOW in DATA MONITOR mode with CONSULT-III.
For specification, refer to EC-606, "Mass Air Flow Sensor".
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in Service $01 with GST.
For specification, refer to EC-606, "Mass Air Flow Sensor".
Is the measurement value within the specification?
YES >> GO TO 7.
NO
>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
grounds. Refer to EC-173, "Diagnosis Procedure".
1.
2.

7.CHECK FUNCTION OF FUEL INJECTOR

1.
2.

With CONSULT-III
Start engine.
Perform POWER BALANCE in ACTIVE TEST mode with CONSULT-III.

Revision: 2007 June

EC-234

G37 Coupe

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

< COMPONENT DIAGNOSIS >
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Start engine and let it idle.
2. Listen to each fuel injector operating sound.

[VQ37VHR]
A

EC

Clicking sound should be heard.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-487, "Diagnosis Procedure".

D
PBIB3332E

8.CHECK FUEL INJECTOR

1.
2.
3.
4.

5.
6.
7.
8.

Turn ignition switch OFF.

Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
Disconnect all fuel injector harness connectors.
Remove fuel tube assembly. Refer to EM-36, "Removal and Installation".
Keep fuel hose and all fuel injectors connected to fuel tube.
For DTC P0171, reconnect fuel injector harness connectors on bank 1.
For DTC P0174, reconnect fuel injector harness connectors on bank 2.
Disconnect all ignition coil harness connectors.
Prepare pans or saucers under each fuel injector.
Crank engine for about 3 seconds.
For DTC P0171, make sure that fuel sprays out from fuel injectors on bank 1.
For DTC P0174, make sure that fuel sprays out from fuel injectors on bank 2.

Fuel should be sprayed evenly for each fuel injector.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace fuel injectors from which fuel does not spray
out. Always replace O-ring with new ones.

PBIB1726E

9.CHECK INTERMITTENT INCIDENT

L

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Revision: 2007 June

EC-235

G37 Coupe

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

DTC Logic

INFOID:0000000001734062

DTC DETECTION LOGIC

With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the A/F sensors 1. The ECM calculates the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too rich.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
Sensor

Density of oxygen in exhaust gas

(Mixture ratio feedback signal)

A/F sensor 1

DTC No.

Input signal to ECM

Trouble diagnosis name

P0172

Fuel injection system too

rich (bank 1)

P0175

Fuel injection system too

rich (bank 2)

ECM function

Actuator

Fuel injection control

DTC detecting condition

Fuel injection system does not operate properly.
The amount of mixture ratio compensation is too
large. (The mixture ratio is too rich.)

Fuel injector

Possible cause

A/F sensor 1
Fuel injector
Exhaust gas leaks
Incorrect fuel pressure
Mass air flow sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Start engine.
Is it difficult to start engine?
YES >> GO TO 3.
NO
>> GO TO 4.

3.RESTART ENGINE
If it is difficult to start engine, the fuel injection system has a malfunction, too.
Crank engine while depressing accelerator pedal.
Does engine start?
YES >> Go to EC-237, "Diagnosis Procedure".
NO
>> Remove spark plugs and check for fouling, etc.

4.PERFORM DTC CONFIRMATION PROCEDURE-II

1. Keep engine idle for at least 10 minutes.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-237, "Diagnosis Procedure".
NO
>> GO TO 5.

5.PERFORM DTC CONFIRMATION PROCEDURE-III

1.
2.

Turn ignition switch OFF and wait at least 10 seconds.

Turn ignition switch ON.

Revision: 2007 June

EC-236

G37 Coupe

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]
< COMPONENT DIAGNOSIS >
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 min- A
utes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following conEC
ditions should be satisfied at the same time.
Engine speed

Engine speed in the freeze frame data 400 rpm

Vehicle speed

Vehicle speed in the freeze frame data 10 km/h (6 MPH)

Engine coolant temperature (T) condition

When the freeze frame data shows lower than 70 C (158 F),
T should be lower than 70 C (158 F).
When the freeze frame data shows higher than or equal to 70 C (158 F),
T should be higher than or equal to 70 C (158 F).

5. Check 1st trip DTC.

Is 1st trip DTC detected?
YES >> Go to EC-237, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734063

1.CHECK EXHAUST GAS LEAK

1.
2.

Start engine and run it at idle.

Listen for an exhaust gas leak before three way catalyst 1.
H

J
PBIB1922E

Is exhaust gas leak detected?

YES >> Repair or replace.
NO
>> GO TO 2.

2.CHECK FOR INTAKE AIR LEAK

Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES >> Repair or replace.
NO
>> GO TO 3.

3.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect corresponding A/F sensor 1 harness connector.
Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

DTC

P0172

P0175

A/F sensor 1
Bank

Connector

F3

Revision: 2007 June

F20

ECM
Terminal

Connector

1
2
1
2

Terminal

Continuity

57
F102

61
65

Existed

66

EC-237

G37 Coupe

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]
< COMPONENT DIAGNOSIS >
5. Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

DTC

P0172

P0175

A/F sensor 1
Bank

Connector

F3

ECM
Terminal

F20

Connector

1
2
1

Terminal

Ground

Continuity

Ground

Not existed

57
F102

61
65
66

6. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK FUEL PRESSURE

1.
2.

Release fuel pressure to zero. Refer to EC-601, "Inspection".

Install fuel pressure gauge and check fuel pressure. Refer to EC-601, "Inspection".
At idling: Approximately 350 kPa (3.57 kg/cm2, 51 psi)

Is the inspection result normal?

YES >> GO TO 5.
NO
>> Replace fuel filter and fuel pump assembly.

5.CHECK MASS AIR FLOW SENSOR

With CONSULT-III
Install all removed parts.
Check MASS AIR FLOW in DATA MONITOR mode with CONSULT-III.
For specification, refer to EC-606, "Mass Air Flow Sensor".
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in Service $01 with GST.
For specification, refer to EC-606, "Mass Air Flow Sensor".
Is the measurement value within the specification?
YES >> GO TO 6.
NO
>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
grounds. Refer to EC-173, "Diagnosis Procedure".
1.
2.

6.CHECK FUNCTION OF FUEL INJECTOR

With CONSULT-III
Start engine.
Perform POWER BALANCE in ACTIVE TEST mode with CONSULT-III.
Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Start engine and let it idle.
2. Listen to each fuel injector operating sound.

1.
2.
3.

Clicking sound should be heard.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-487, "Diagnosis Procedure".

PBIB3332E

7.CHECK FUELINJECTOR
Revision: 2007 June

EC-238

G37 Coupe

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Remove fuel injector assembly. Refer to EM-36, "Removal and Installation".
Keep fuel hose and all fuel injectors connected to fuel tube.
A
2. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3. Disconnect all fuel injector harness connectors.
4. Disconnect all ignition coil harness connectors.
EC
5. Prepare pans or saucers under each fuel injectors.
6. Crank engine for about 3 seconds.
Make sure fuel does not drip from fuel injector.
C
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace the fuel injectors from which fuel is dripping. Always replace O-ring with new one.
D

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

F

Revision: 2007 June

EC-239

G37 Coupe

P0181 FTT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0181 FTT SENSOR

Description

INFOID:0000000001734064

The fuel tank temperature sensor is used to detect the fuel temperature inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temperature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.
<Reference data>
Fluid temperature C (F)

Voltage* V

Resistance k

20 (68)

3.5

2.3 - 2.7

50 (122)

2.2

0.79 - 0.90

SEF012P

*: These data are reference values and are measured between ECM terminal 106 (Fuel tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000001734065

DTC DETECTION LOGIC

DTC No.

P0181

Trouble diagnosis name

DTC detecting condition

Fuel tank temperature

sensor circuit range/performance

Rationally incorrect voltage from the sensor is

sent to ECM, compared with the voltage signals
from engine coolant temperature sensor and intake air temperature sensor.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted)
Fuel tank temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1. Turn ignition switch ON and wait at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-241, "Diagnosis Procedure".
NO
>> GO TO 3.

3.CHECK ENGINE COOLANT TEMPERATURE

With CONSULT-III
Select COOLAN TEMP/S in DATA MONITOR with CONSULT-III.
Check COOLAN TEMP/S value.
With GST
Follow the procedure With CONSULT-III above.
COOLAN TEMP/S less than 60C (140F)?
YES >> INSPECTION END
NO
>> GO TO 4.
1.
2.

Revision: 2007 June

EC-240

G37 Coupe

P0181 FTT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

4.PERFORM DTC CONFIRMATION PROCEDURE-II

With CONSULT-III
1. Cool engine down until COOLAN TEMP/S is less than 60C (140F).
2. Wait at least 10 seconds.
3. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-241, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

EC

D
INFOID:0000000001734066

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Go to MWI-54, "Component Function Check".

3.CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect fuel level sensor unit and fuel pump harness connector.
Turn ignition switch ON.
Check the voltage between fuel level sensor unit and fuel pump harness connector and ground.

Fuel level sensor unit and

fuel pump
Connector

Terminal

B22

K
Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M7, B1
Harness for open or short between ECM and fuel level sensor unit and fuel pump

>> Repair open circuit or short to ground or short to power in harness or connector.

5.CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect unified meter and A/C amp. harness connector.
Check the continuity between fuel level sensor unit and fuel pump harness connector and unified meter
and A/C amp. harness connector.

Revision: 2007 June

EC-241

G37 Coupe

P0181 FTT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Fuel level sensor unit
and fuel pump

Unified meter and A/C

amp.

Connector

Terminal

Connector

Terminal

B22

M67

58

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M7, B1
Harness for open or short between fuel level sensor unit and fuel pump and unified meter and A/C amp.
>> Repair open circuit or short to ground or short to power in harness or connector.

7.CHECK FUEL TANK TEMPERATURE SENSOR

Refer to EC-242, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace fuel level sensor unit and fuel pump.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734067

1.CHECK FUEL TANK TEMPERATURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect fuel level sensor unit and fuel pump harness connector.
Remove fuel level sensor unit.
Check resistance between fuel level sensor unit and fuel pump
terminals by heating with hot water as shown in the figure.

Terminals
4 and 5

Condition
Temperature C (F)

Resistance
20 (68)
50 (122)

2.3 - 2.7 k
0.79 - 0.90

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace fuel level sensor unit and fuel pump.
JMBIA0167ZZ

Revision: 2007 June

EC-242

G37 Coupe

P0182, P0183 FTT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0182, P0183 FTT SENSOR

Description

INFOID:0000000001910860

The fuel tank temperature sensor is used to detect the fuel temperature inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temperature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.
<Reference data>

EC

D
Fluid temperature C (F)

Voltage* V

Resistance k

20 (68)

3.5

2.3 - 2.7

50 (122)

2.2

0.79 - 0.90

SEF012P

*: These data are reference values and are measured between ECM terminal 106 (Fuel tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000001734069

DTC DETECTION LOGIC

H
DTC No.

Trouble diagnosis name

DTC detecting condition

P0182

Fuel tank temperature

sensor circuit low input

An excessively low voltage from the sensor is

sent to ECM.

P0183

Fuel tank temperature

sensor circuit high input

An excessively high voltage from the sensor is

sent to ECM.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted.)
Fuel tank temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-243, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

O
INFOID:0000000001910861

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.
Revision: 2007 June

EC-243

G37 Coupe

P0182, P0183 FTT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Go to MWI-54, "Component Function Check".

3.CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect fuel level sensor unit and fuel pump harness connector.
Turn ignition switch ON.
Check the voltage between fuel level sensor unit and fuel pump harness connector and ground.

Fuel level sensor unit and

fuel pump
Connector

Terminal

B22

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M7, B1
Harness for open or short between ECM and fuel level sensor unit and fuel pump
>> Repair open circuit or short to ground or short to power in harness or connector.

5.CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect unified meter and A/C amp. harness connector.
Check the continuity between fuel level sensor unit and fuel pump harness connector and unified meter
and A/C amp. harness connector.

Fuel level sensor unit

and fuel pump

Unified meter and A/C

amp.

Connector

Terminal

Connector

Terminal

B22

M67

58

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M7, B1
Harness for open or short between fuel level sensor unit and fuel pump and unified meter and A/C amp.
>> Repair open circuit or short to ground or short to power in harness or connector.

7.CHECK FUEL TANK TEMPERATURE SENSOR

Refer to EC-245, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace fuel level sensor unit and fuel pump.
Revision: 2007 June

EC-244

G37 Coupe

P0182, P0183 FTT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

EC

Component Inspection

INFOID:0000000001910862

1.CHECK FUEL TANK TEMPERATURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect fuel level sensor unit and fuel pump harness connector.
Remove fuel level sensor unit.
Check resistance between fuel level sensor unit and fuel pump
terminals by heating with hot water as shown in the figure.

E
Terminals
4 and 5

Condition
Temperature

C (F)

Resistance
20 (68)
50 (122)

2.3 - 2.7

0.79 - 0.90 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace fuel level sensor unit and fuel pump.

G
JMBIA0167ZZ

Revision: 2007 June

EC-245

G37 Coupe

P0196 EOT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0196 EOT SENSOR

Description

INFOID:0000000001734072

The engine oil temperature sensor is used to detect the engine oil
temperature. The sensor modifies a voltage signal from the ECM.
The modified signal returns to the ECM as the engine oil temperature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

SEF594K

<Reference data>
Engine oil temperature
C (F)

Voltage*

Resistance

10 (14)

4.4

7.0 - 11.4

20 (68)

3.5

2.1 - 2.9

50 (122)

2.2

0.68 - 1.00

90 (194)

0.9

0.236 - 0.260

110 (230)

0.6

0.143 - 0.153

SEF012P

*: These data are reference values and are measured between ECM terminal 78
(Engine oil temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000001734073

DTC DETECTION LOGIC

NOTE:
If DTC P0196 is displayed with P0197 or P0198, first perform the trouble diagnosis for DTC P0197 or
P0198. Refer to EC-249, "DTC Logic".
DTC No.

P0196

Trouble diagnosis name

Engine oil temperature
sensor range/performance

DTC detecting condition

Rationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage signals
from engine coolant temperature sensor and intake air temperature sensor.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted)
Engine oil temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
>> GO TO 2.
Revision: 2007 June

EC-246

G37 Coupe

P0196 EOT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1. Start engine and warm it up to normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and let it idle for 5 minutes and 10 seconds.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> EC-247, "Diagnosis Procedure".
NO
>> GO TO 3.

EC

3.PERFORM DTC CONFIRMATION PROCEDURE-II

With CONSULT-III
Select DATA MONITOR mode with CONSULT-III.
Check that COOLAN TEMP/S indicates above 80C (176F).
If it is above 80C (176F), go to the following steps.
If it is below 80C (176F), warm engine up until COOLAN TEMP/S indicates more than 80C (176F).
Then go to the following steps.
3. Turn ignition switch OFF and soak the vehicle at cool place.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Turn ignition switch ON.
NOTE:
Do not turn ignition switch OFF until step 10.
7. Select DATA MONITOR mode with CONSULT-III.
8. Check the following.
1.
2.

COOLAN TEMP/S

Below 40C (104F)

INT/A TEMP SE

Below 40C (104F)

Difference between COOLAN TEMP/S and INT/A TEMP SE

Within 6C (11F)

INFOID:0000000001734074

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK ENGINE OIL TEMPERATURE SENSOR

Refer to EC-248, "Component Inspection".
Is the inspection result normal?
Revision: 2007 June

If they are within the specified range, go to following steps.

If they are out of the specified range, soak the vehicle to meet the above conditions. Then go to following
steps.
NOTE:
Do not turn ignition switch OFF.
If it is supposed to need a long period of time, do not deplete the battery.
9. Start engine and let it idle for 5 minutes.
10. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> EC-247, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

EC-247

G37 Coupe

P0196 EOT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 3.
NO
>> Replace engine oil temperature sensor.

3.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734075

1.CHECK ENGINE OIL TEMPERATURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect engine oil temperature sensor harness connector.
Remove engine oil temperature sensor.
Check resistance between engine oil temperature sensor terminals by heating with hot water as shown in the figure.
Terminals

Condition

Resistance
20 (68)

1 and 2

Temperature

C (F)

50 (122)
90 (194)

2.1 - 2.9

0.68 - 1.00 k
0.236 - 0.260

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace engine oil temperature sensor.

Revision: 2007 June

EC-248

JMBIA0080ZZ

G37 Coupe

P0197, P0198 EOT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0197, P0198 EOT SENSOR

Description

INFOID:0000000001910867

The engine oil temperature sensor is used to detect the engine oil
temperature. The sensor modifies a voltage signal from the ECM.
The modified signal returns to the ECM as the engine oil temperature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

EC

SEF594K

<Reference data>
F
Engine oil temperature
C (F)

Voltage*

Resistance k

10 (14)

4.4

7.0 - 11.4

20 (68)

3.5

2.1 - 2.9

50 (122)

2.2

0.68 - 1.00

90 (194)

0.9

0.236 - 0.260

110 (230)

0.6

0.143 - 0.153

H
SEF012P

*: These data are reference values and are measured between ECM terminal 78
(Engine oil temperature sensor) and ground.

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000001734077

DTC DETECTION LOGIC

Trouble Diagnosis
Name

DTC Detecting Condition

P0197

Engine oil temperature sensor circuit low

input

An excessively low voltage from the sensor is

sent to ECM.

P0198

Engine oil temperature sensor circuit

high input

An excessively high voltage from the sensor is

sent to ECM.

DTC No.

Possible Cause

Harness or connectors
(The sensor circuit is open or shorted.)
Engine oil temperature sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and wait at least 5 seconds.

Revision: 2007 June

EC-249

G37 Coupe

P0197, P0198 EOT SENSOR

< COMPONENT DIAGNOSIS >
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-250, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

[VQ37VHR]

INFOID:0000000001734078

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK EOT SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect engine oil temperature (EOT) sensor harness connector.

Turn ignition switch ON.
Check the voltage between EOT sensor harness connector and ground.
EOT sensor

Connector

Terminal

F38

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK EOT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between EOT sensor harness connector and ECM harness connector.
EOT sensor

ECM

Connector

Terminal

Connector

Terminal

F38

F102

84

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK ENGINE OIL TEMPERATURE SENSOR

Refer to EC-250, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace engine oil temperature sensor.

5.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910868

1.CHECK ENGINE OIL TEMPERATURE SENSOR

1.

Turn ignition switch OFF.

Revision: 2007 June

EC-250

G37 Coupe

P0197, P0198 EOT SENSOR

< COMPONENT DIAGNOSIS >
2. Disconnect engine oil temperature sensor harness connector.
3. Remove engine oil temperature sensor.
4. Check resistance between engine oil temperature sensor terminals by heating with hot water as shown in the figure.

[VQ37VHR]
A

EC
Terminals

Condition

Resistance
20 (68)

1 and 2

Temperature C (F)

50 (122)
90 (194)

2.1 - 2.9 k
0.68 - 1.00

0.236 - 0.260 k

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace engine oil temperature sensor.

D
JMBIA0080ZZ

Revision: 2007 June

EC-251

G37 Coupe

P0222, P0223, P2132, P2133 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0222, P0223, P2132, P2133 TP SENSOR

Description

INFOID:0000000001910837

Electric throttle control actuator consists of throttle control motor,

throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

PBIB0145E

INFOID:0000000001734081

DTC DETECTION LOGIC

NOTE:
If DTC P0222, P0223, P2132 or P2133 is displayed with DTC P0643, first perform the trouble diagnosis
for DTC P0643. Refer to EC-358, "DTC Logic".
DTC No.

Trouble diagnosis name

DTC detecting condition

P0222

Throttle position sensor

1 (bank 1) circuit low input

An excessively low voltage from the TP sensor

1 is sent to ECM.

P0223

Throttle position sensor

1 (bank 1) circuit high input

An excessively high voltage from the TP sensor

1 is sent to ECM.

P2132

Throttle position sensor

1 (bank 2) circuit low input

An excessively low voltage from the TP sensor

1 is sent to ECM.

P2133

Throttle position sensor

1 (bank 2) circuit high input

An excessively high voltage from the TP sensor

1 is sent to ECM.

Possible cause

Harness or connectors
(TP sensor 1 circuit is open or shorted.)
Electric throttle control actuator
(TP sensor 1)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-253, "Diagnosis Procedure".
NO
>> INSPECTION END

Revision: 2007 June

EC-252

G37 Coupe

P0222, P0223, P2132, P2133 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001734082

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

EC

2.CHECK THROTTLE POSITION SENSOR 1 POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect electric throttle control actuator harness connector.

Turn ignition switch ON.
Check the voltage between electric throttle control actuator harness connector and ground.

E
DTC

Electric throttle control actuator

Bank

Connector

Terminal

P0222, P0223

F6

P2132, P2133

F27

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK THROTTLE POSITION SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

P0222, P0223

F6

P2132, P2133

F27

ECM
Connector

Terminal
40

F101

48

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK THROTTLE POSITION SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between electric throttle control actuator harness connector and ECM harness connector.
N
DTC

Electric throttle control actuator

Bank

Connector

Terminal

P0222, P0223

F6

P2132, P2133

F27

ECM
Connector
F101

Terminal
30
31

Continuity

O
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK THROTTLE POSITION SENSOR

Refer to EC-254, "Component Inspection".
Revision: 2007 June

EC-253

G37 Coupe

P0222, P0223, P2132, P2133 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-254, "Special Repair Requirement".
>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910838

1.CHECK THROTTLE POSITION SENSOR

1.
2.
3.
4.
5.
6.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Perform EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
Turn ignition switch ON.
Set selector lever to D (A/T) or 1st (M/T) position.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

Ground

Condition

30 [TP sensor 1 (bank 1)]

31 [TP sensor 1 (bank 2)]
F101

Ground

Accelerator pedal

34 [TP sensor 2 (bank 1)]

35 [TP sensor 2 (bank 2)]

Voltage

Fully released

More than 0.36V

Fully depressed

Less than 4.75V

Fully released

Less than 4.75V

Fully depressed

More than 0.36V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-254, "Special Repair Requirement".
>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910839

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"
>> END

Revision: 2007 June

EC-254

G37 Coupe

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

DTC Logic

A
INFOID:0000000001734085

DTC DETECTION LOGIC

EC

When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the crankshaft position (CKP) sensor (POS) signal to vary, ECM can determine that a misfire is occurring.
C
Sensor
Crankshaft position sensor (POS)

Input signal to ECM

Engine speed

ECM function
On board diagnosis of misfire

The misfire detection logic consists of the following two conditions.

1. One Trip Detection Logic (Three Way Catalyst Damage)
On the 1st trip that a misfire condition occurs that can damage the three way catalyst (TWC) due to overheating, the MIL will blink.
When a misfire condition occurs, the ECM monitors the CKP sensor signal every 200 engine revolutions
for a change.
When the misfire condition decreases to a level that will not damage the TWC, the MIL will turn off.
If another misfire condition occurs that can damage the TWC on a second trip, the MIL will blink.
When the misfire condition decreases to a level that will not damage the TWC, the MIL will remain on.
If another misfire condition occurs that can damage the TWC, the MIL will begin to blink again.
2. Two Trip Detection Logic (Exhaust quality deterioration)
For misfire conditions that will not damage the TWC (but will affect vehicle emissions), the MIL will only
light when the misfire is detected on a second trip. During this condition, the ECM monitors the CKP sensor signal every 1,000 engine revolutions.
A misfire malfunction can be detected on any one cylinder or on multiple cylinders.
DTC No.

Trouble diagnosis name

DTC detecting condition

P0300

Multiple cylinder misfire detected

Multiple cylinder misfire.

P0301

No.1 cylinder misfire detected

No. 1 cylinder misfires.

P0302

No. 2 cylinder misfire detected

No. 2 cylinder misfires.

P0303

No. 3 cylinder misfire detected

No. 3 cylinder misfires.

P0304

No. 4 cylinder misfire detected

No. 4 cylinder misfires.

P0305

No. 5 cylinder misfire detected

No. 5 cylinder misfires.

P0306

No. 6 cylinder misfire detected

No. 6 cylinder misfires.

Possible cause

Improper spark plug

Insufficient compression
Incorrect fuel pressure
The fuel injector circuit is open or shorted
Fuel injector
Intake air leak
The ignition signal circuit is open or shorted
Lack of fuel
Signal plate
A/F sensor 1
Incorrect PCV hose connection

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1.
2.
3.
4.
5.
6.

Start engine and warm it up to normal operating temperature.

Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Restart engine and let it idle for about 15 minutes.
Check 1st trip DTC.

Revision: 2007 June

EC-255

G37 Coupe

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

< COMPONENT DIAGNOSIS >
Is 1st trip DTC detected?
YES >> Go to EC-256, "Diagnosis Procedure".
NO
>> GO TO 3.

[VQ37VHR]

3.PERFORM DTC CONFIRMATION PROCEDURE-II

1.
2.
3.
4.

Turn ignition switch OFF and wait at least 10 seconds.

Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for a certain
time. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following conditions should be satisfied at the same time.
CAUTION:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws when
driving.

Engine speed

Engine speed in the freeze frame data 400 rpm

Vehicle speed

Vehicle speed in the freeze frame data 10 km/h (6 MPH)

Engine coolant temperature (T)

condition

When the freeze frame data shows lower than 70 C (158 F),
T should be lower than 70 C (158 F).
When the freeze frame data shows higher than or equal to 70 C (158 F),
T should be higher than or equal to 70 C (158 F).

The time to driving varies according to the engine speed in the freeze frame data.
Engine speed

Time

Around 1,000 rpm

Approximately 10 minutes

Around 2,000 rpm

Approximately 5 minutes

More than 3,000 rpm

Approximately 3.5 minutes

5. Check 1st trip DTC.

Is 1st trip DTC detected?
YES >> Go to EC-256, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734086

1.CHECK FOR INTAKE AIR LEAK AND PCV HOSE

1. Start engine and run it at idle speed.
2. Listen for the sound of the intake air leak.
3. Check PCV hose connection.
Is intake air leak detected?
YES >> Discover air leak location and repair.
NO
>> GO TO 2.

2.CHECK FOR EXHAUST SYSTEM CLOGGING

Stop engine and visually check exhaust tube, three way catalyst and muffler for dents.
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 3.
YES-2 >> Without CONSULT-III: GO TO 4.
NO
>> Repair or replace it.

3.PERFORM POWER BALANCE TEST

1.
2.

With CONSULT-III
Start engine.
Perform POWER BALANCE in ACTIVE TEST mode with CONSULT-III.

Revision: 2007 June

EC-256

G37 Coupe

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

< COMPONENT DIAGNOSIS >
3. Make sure that each circuit produces a momentary engine speed drop.
Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 4.

[VQ37VHR]
A

4.CHECK FUNCTION OF FUEL INJECTOR-I

1.
2.

EC

Start engine and let it idle.

Listen to each fuel injector operating sound.

Clicking sound should be heard.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-487, "Diagnosis Procedure".

PBIB3332E

5.CHECK FUNCTION OF IGNITION COIL-I

CAUTION:
Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse (1) in IPDM E/R (2) to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following procedure.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel
pressure.
5. Turn ignition switch OFF.
6. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be
checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
11. Crank engine for about 3 seconds, and check whether spark is
generated between the spark plug and the grounded metal portion.

J
JMBIA0021ZZ

Spark should be generated.

CAUTION:
Do not approach to the spark plug and the ignition coil
JMBIA0066GB
within 50 cm (19.7 in). Be careful not to get an electrical
shock while checking, because the electrical discharge
voltage becomes 20kV or more.
It might cause to damage the ignition coil if the gap of more than 17 mm (0.66 in) is taken.
NOTE:
When the gap is less than 13 mm (0.52 in), the spark might be generated even if the coil is malfunctioning.
Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 6.

Revision: 2007 June

EC-257

G37 Coupe

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

6.CHECK FUNCTION OF IGNITION COIL-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect spark plug and connect a known-good spark plug.
Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and
the grounded metal portion.
Spark should be generated.

Is the inspection result normal?

YES >> GO TO 7.
NO
>> Check ignition coil, power transistor and their circuits. Refer to EC-498, "Diagnosis Procedure".

7.CHECK SPARK PLUG

Check the initial spark plug for fouling, etc.
Is the inspection result normal?
YES >> Replace spark plug(s) with standard type one(s). For
spark plug type, refer to EM-16, "Inspection".
NO
>> Repair or clean spark plug. Then GO TO 8.

SEF156I

8.CHECK FUNCTION OF IGNITION COIL-III

1.
2.

Reconnect the initial spark plugs.

Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and
the grounded portion.
Spark should be generated.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace spark plug(s) with standard type one(s). For spark plug type, refer to EM-15, "Removal
and Installation".

9.CHECK COMPRESSION PRESSURE

Check compression pressure. Refer to EM-16, "Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Check pistons, piston rings, valves, valve seats and cylinder head gaskets.

10.CHECK FUEL PRESSURE

1.
2.
3.

Install all removed parts.

Release fuel pressure to zero. Refer to EC-601, "Inspection".
Install fuel pressure gauge and check fuel pressure. Refer to EC-601, "Inspection".
At idle: Approximately 350 kPa (3.57 kg/cm2, 51 psi)

Is the inspection result normal?

YES >> GO TO 12.
NO
>> GO TO 11.

11.DETECT MALFUNCTIONING PART

Check fuel hoses and fuel tubes for clogging.
Is the inspection result normal?
YES >> Replace fuel filter and fuel pump assembly.
NO
>> Repair or replace.
Revision: 2007 June

EC-258

G37 Coupe

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

12.CHECK IDLE SPEED AND IGNITION TIMING

For procedure, refer to EC-13, "BASIC INSPECTION : Special Repair Requirement".

For specification, refer to EC-606, "Idle Speed" and EC-606, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 13.
NO
>> Follow the EC-13, "BASIC INSPECTION : Special Repair Requirement".

EC

13.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect corresponding A/F sensor 1 harness connector.
Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
A/F sensor 1

Bank

Connector

F3

5.

F20

ECM
Terminal

Connector

Terminal

57

61

F102

65

Continuity

F
Existed

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.
A/F sensor 1

Bank

Connector

F3

F20

ECM
Terminal

Connector

Terminal

57

61

F102

65

Ground

Continuity

I
Ground

Not existed

66

6. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

14.CHECK A/F SENSOR 1 HEATER

Refer to EC-157, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace (malfunctioning) A/F sensor 1.

15.CHECK MASS AIR FLOW SENSOR

With CONSULT-III
Check mass air flow sensor signal in DATA MONITOR mode with CONSULT-III.
For specification, refer to EC-606, "Mass Air Flow Sensor".
With GST
Check mass air flow sensor signal in Service $01 with GST.
For specification, refer to EC-606, "Mass Air Flow Sensor".
Is the measurement value within the specification?
YES >> GO TO 16.
NO
>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-173, "Diagnosis Procedure".

16.CHECK SYMPTOM MATRIX CHART

Check items on the rough idle symptom in EC-589, "Symptom Table".
Revision: 2007 June

EC-259

G37 Coupe

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 17.
NO
>> Repair or replace.

17.ERASE THE 1ST TRIP DTC

Some tests may cause a 1st trip DTC to be set.
Erase the 1st trip DTC from the ECM memory after performing the tests. Refer to EC-107, "Diagnosis Description".
>> GO TO 18.

18.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Revision: 2007 June

EC-260

G37 Coupe

P0327, P0328, P0332, P0333 KS

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0327, P0328, P0332, P0333 KS

Description

INFOID:0000000001734087

The knock sensor is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A EC
knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a
voltage signal and sent to the ECM.

DTC Logic

INFOID:0000000001734088

DTC DETECTION LOGIC

D
Trouble diagnosis
name

DTC detected condition

P0327

Knock sensor (bank 1)

circuit low input

An excessively low voltage from the sensor is

sent to ECM.

P0328

Knock sensor (bank 1)

circuit high input

An excessively high voltage from the sensor

is sent to ECM.

P0332

Knock sensor (bank 2)

circuit low input

An excessively low voltage from the sensor is

sent to ECM.

P0333

Knock sensor (bank 2)

circuit high input

An excessively high voltage from the sensor

is sent to ECM.

DTC No.

Possible cause

E
Harness or connectors
(The sensor circuit is open or shorted.)
Knock sensor

DTC CONFIRMATION PROCEDURE

H

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and run it for at least 5 seconds at idle speed.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-261, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

M
INFOID:0000000001734089

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK KNOCK SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.

Disconnect knock sensor harness connector and ECM harness connector.

Check the continuity between knock sensor harness connector and ECM harness connector.

Revision: 2007 June

EC-261

G37 Coupe

P0327, P0328, P0332, P0333 KS

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

Knock sensor

ECM

Bank

Connector

Terminal

P0327, P0328

F203

P0332, P0333

F202

Connector

Terminal

F102

72

Continuity

Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F9, F201
Harness for open or short between knock sensor and ECM
>> Repair open circuit or short to power in harness or connectors.

4.CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between knock sensor harness connector and ECM harness connector.

DTC

Knock sensor

ECM

Bank

Connector

Terminal

P0327, P0328

F203

P0332, P0333

F202

Connector

Terminal
73

F102

69

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F9, F201
Harness for open or short between ECM and knock sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK KNOCK SENSOR

Refer to EC-262, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Replace malfunctioning knock sensor.

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734090

1.CHECK KNOCK SENSOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect knock sensor harness connector.
Check resistance between knock sensor terminals as follows.
NOTE:

Revision: 2007 June

EC-262

G37 Coupe

P0327, P0328, P0332, P0333 KS

< COMPONENT DIAGNOSIS >
It is necessary to use an ohmmeter which can measure more than 10 M.

[VQ37VHR]
A

Terminals

Resistance

1 and 2

Approx. 532 - 588 k [at 20C (68F)]

CAUTION:
Do not use any knock sensors that have been dropped or physically damaged. Use only new ones.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace malfunctioning knock sensor.

EC

Revision: 2007 June

EC-263

G37 Coupe

P0335 CKP SENSOR (POS)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0335 CKP SENSOR (POS)

Description

INFOID:0000000001734091

The crankshaft position sensor (POS) is located on the cylinder

block facing the gear teeth (cogs) of the signal plate. It detects the
fluctuation of the engine revolution.
The sensor consists of a permanent magnet and Hall IC.
When the engine is running, the high and low parts of the teeth
cause the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor
changes.
The ECM receives the voltage signal and detects the fluctuation of
the engine revolution.
ECM receives the signals as shown in the figure.

JMBIA0062ZZ

JMBIA0001GB

DTC Logic

INFOID:0000000001734092

DTC DETECTION LOGIC

DTC No.

P0335

Trouble diagnosis name

Crankshaft position sensor (POS) circuit

DTC detecting condition

Possible cause

The crankshaft position sensor (POS) signal

is not detected by the ECM during the first
few seconds of engine cranking.
The proper pulse signal from the crankshaft
position sensor (POS) is not sent to ECM
while the engine is running.
The crankshaft position sensor (POS) signal
is not in the normal pattern during engine running.

Harness or connectors
[CKP sensor (POS) circuit is open or
shorted.]
(APP sensor 2 circuit is shorted.)
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
(Brake booster pressure sensor circuit is
shorted)
Crankshaft position sensor (POS)
Accelerator pedal position sensor
EVAP control system pressure sensor
Refrigerant pressure sensor
Brake booster pressure snsor.
Signal plate

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V with ignition switch ON.
Revision: 2007 June

EC-264

G37 Coupe

P0335 CKP SENSOR (POS)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and let it idle for at least 5 seconds.

If engine does not start, crank engine for at least 2 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-265, "Diagnosis Procedure".
NO
>> INSPECTION END

EC

Diagnosis Procedure

INFOID:0000000001734093

1.CHECK GROUND CONNECTION

E

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK CRANKSHAFT POSITION (CKP) SENSOR (POS) POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect crankshaft position (CKP) sensor (POS) harness connector.

Turn ignition switch ON.
Check the voltage between CKP sensor (POS) harness connector and ground.
CKP sensor (POS)

Connector

Terminal

F2

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 3.

3.CHECK CRANKSHAFT POSITION (CKP) SENSOR (POS) POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch ON.

Disconnect ECM harness connector.
Check the continuity between CKP sensor (POS) harness connector and ECM harness connector.
CKP sensor (POS)

ECM

Connector

Terminal

Connector

Terminal

F2

F101

46

Continuity

M
Existed

Is the inspection result normal?

YES >> GO TO 4.
NO
>> Repair open circuit.

4.CHECK CRANKSHAFT POSITION (CKP) SENSOR (POS) POWER SUPPLY CIRCUIT-III

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector
F101

Sensor

Terminal

Name

45

Brake booster pressure sensor

46

CKP sensor (POS)

Revision: 2007 June

P
Connector
E48
F2

EC-265

Terminal
1

G37 Coupe

P0335 CKP SENSOR (POS)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

M107

Sensor

Terminal

Name

Connector

Terminal

103

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

Is the inspection result normal?

YES >> GO TO 5.
NO
>> Repair short to ground or short to power in harness or connectors.

5.CHECK COMPONENTS
Check the following.
Brake booster pressure sensor (Refer to EC-352, "Component Inspection".)
EVAP control system pressure sensor (Refer to EC-306, "Component Inspection".)
Refrigerant pressure sensor (Refer to HAC-85, "Diagnosis Procedure".)
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace malfunctioning component.

6.CHECK APP SENSOR

Refer to EC-460, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 12.
NO
>> GO TO 7.

7.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-460, "Special Repair Requirement".
>> INSPECTION END

8.CHECK CKP SENSOR (POS) GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between CKP sensor (POS) harness connector and ECM harness connector.
CKP sensor (POS)

ECM

Connector

Terminal

Connector

Terminal

F2

F101

47

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK CKP SENSOR (POS) INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between CKP sensor (POS) harness connector and ECM harness connector.
CKP sensor (POS)

ECM

Connector

Terminal

Connector

Terminal

F2

F101

37

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 10.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.
Revision: 2007 June

EC-266

G37 Coupe

P0335 CKP SENSOR (POS)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

10.CHECK CRANKSHAFT POSITION SENSOR (POS)

Refer to EC-267, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 11.
NO
>> Replace crankshaft position sensor (POS).

EC

11.CHECK GEAR TOOTH

C

Visually check for chipping signal plate gear tooth.

Is the inspection result normal?
YES >> GO TO 12.
NO
>> Replace the signal plate.

12.CHECK INTERMITTENT INCIDENT

E

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734094

1.CHECK CRANKSHAFT POSITION SENSOR (POS)-I

1. Turn ignition switch OFF.

2. Loosen the fixing bolt of the sensor.
3. Disconnect crankshaft position sensor (POS) harness connector.
4. Remove the sensor.
5. Visually check the sensor for chipping.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Replace crankshaft position sensor (POS).

K
JMBIA0063ZZ

2.CHECK CRANKSHAFT POSITION SENSOR (POS)-II

Check resistance between crankshaft position sensor (POS) terminals as follows.

Terminals (Polarity)

Resistance

1 (+) - 2 (-)
1 (+) - 3 (-)

Except 0 or [at 25C (77F)]

2 (+) - 3 (-)

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace crankshaft position sensor (POS).

Revision: 2007 June

EC-267

G37 Coupe

P0340, P0345 CMP SENSOR (PHASE)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0340, P0345 CMP SENSOR (PHASE)

Description

INFOID:0000000001734095

The camshaft position sensor (PHASE) senses the retraction of

camshaft (INT) to identify a particular cylinder. The camshaft position
sensor (PHASE) senses the piston position.
When the crankshaft position sensor (POS) system becomes inoperative, the camshaft position sensor (PHASE) provides various controls of engine parts instead, utilizing timing of cylinder identification
signals.
The sensor consists of a permanent magnet and Hall IC.
When engine is running, the high and low parts of the teeth cause
the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor changes.
ECM receives the signals as shown in the figure.

JMBIA0064ZZ

JMBIA0001GB

DTC Logic

INFOID:0000000001734096

DTC DETECTION LOGIC

NOTE:
If DTC P0340 or P0345 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-358, "DTC Logic".
DTC No.

P0340

Trouble diagnosis name

DTC detecting condition

Camshaft position sensor (PHASE) (bank 1)

circuit
The cylinder No. signal is not sent to ECM for
the first few seconds during engine cranking.
The cylinder No. signal is not sent to ECM
during engine running.
The cylinder No. signal is not in the normal
pattern during engine running.

P0345

Camshaft position sensor (PHASE) (bank 2)

circuit

Possible cause
Harness or connectors
[CMP sensor (PHASE) (bank 1) circuit is
open or shorted.]
Camshaft position sensor (PHASE)
(bank 1)
Camshaft (INT)
Starter motor
Starting system circuit
Dead (Weak) battery
Harness or connectors
[CMP sensor (PHASE) (bank 2) circuit is
open or shorted.]
Camshaft position sensor (PHASE)
(bank 2)
Camshaft (INT)
Starter motor
Starting system circuit
Dead (Weak) battery

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
Revision: 2007 June

EC-268

G37 Coupe

P0340, P0345 CMP SENSOR (PHASE)

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
A
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V with igniEC
tion switch ON.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE-I

1.

Start engine and let it idle for at least 5 seconds.

If engine does not start, crank engine for at least 2 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-269, "Diagnosis Procedure".
NO
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE-I

1. Maintaining engine speed at more than 800 rpm for at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-269, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734097

1.CHECK STARTING SYSTEM

I

Turn ignition switch to START position.

Does the engine turn over? Does the starter motor operate?
YES >> GO TO 2.
NO
>> Check starting system. (Refer to EC-9, "Work Flow".)

2.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace ground connection.

3.CHECK CAMSHAFT POSITION (CMP) SENSOR (PHASE) POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect camshaft position (CMP) sensor (PHASE) harness connector.

Turn ignition switch ON.
Check the voltage between CMP sensor (PHASE) harness connector and ground.

N
DTC

CMP sensor (PHASE)

Bank

Connector

Terminal

P0340

F5

P0345

F18

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK CMP SENSOR (PHASE) GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between CMP sensor (PHASE) harness connector and ECM harness connector.

Revision: 2007 June

EC-269

G37 Coupe

P0340, P0345 CMP SENSOR (PHASE)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

CMP sensor (PHASE)

Bank

Connector

Terminal

P0340

F5

P0345

F18

ECM
Connector

Terminal

Continuity

92

F102

Existed

96

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F107, F106
Harness for open or short between CMP sensor (PHASE) and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK CMP SENSOR (PHASE) INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between CMP sensor (PHASE) harness connector and ECM harness connector.

DTC

CMP sensor (PHASE)

Bank

Connector

Terminal

P0340

F5

P0345

F18

ECM
Connector
F102

Terminal

Continuity

59
63

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> GO TO 7.

7.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F107, F106
Harness for open or short between CMP sensor (PHASE) and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

8.CHECK CAMSHAFT POSITION SENSOR (PHASE)

Refer to EC-271, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace malfunctioning camshaft position sensor (PHASE).

9.CHECK CAMSHAFT (INTAKE)

Check the following.
Accumulation of debris to the signal plate of camshaft front end
Chipping signal plate of camshaft front end
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Remove debris and clean the signal plate of camshaft
front end or replace camshaft.

JMBIA0962ZZ

Revision: 2007 June

EC-270

G37 Coupe

P0340, P0345 CMP SENSOR (PHASE)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

10.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

EC

Component Inspection

INFOID:0000000001734098

1.CHECK CAMSHAFT POSITION SENSOR (PHASE)-I

1. Turn ignition switch OFF.

2. Loosen the fixing bolt of the sensor.
3. Disconnect camshaft position sensor (PHASE) harness connector.
4. Remove the sensor.
5. Visually check the sensor for chipping.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Replace malfunctioning camshaft position sensor
(PHASE).

G
JMBIA0065ZZ

2.CHECK CAMSHAFT POSITION SENSOR (PHASE)-II

Check resistance camshaft position sensor (PHASE) terminals as follows.

I
Terminals (Polarity)

Resistance

1 (+) - 2 (-)
1 (+) - 3 (-)

Except 0 or [at 25C (77F)]

2 (+) - 3 (-)

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace malfunctioning camshaft position sensor (PHASE).

Revision: 2007 June

EC-271

G37 Coupe

P0420, P0430 THREE WAY CATALYST FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0420, P0430 THREE WAY CATALYST FUNCTION

DTC Logic

INFOID:0000000001734099

DTC DETECTION LOGIC

The ECM monitors the switching frequency ratio of air fuel ratio (A/F) sensor 1 and heated oxygen sensor 2.
A three way catalyst 1 with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will
increase.
When the frequency ratio of A/F sensor 1 and heated oxygen sensor 2 approaches a specified limit value, the
three way catalyst 1 malfunction is diagnosed.

PBIB1923E

DTC No.
P0420

P0430

Trouble diagnosis name

Catalyst system efficiency
below threshold (bank 1)
Catalyst system efficiency
below threshold (bank 2)

DTC detecting condition

Three way catalyst (manifold) does not operate properly.

Three way catalyst (manifold) does not
have enough oxygen storage capacity.

Possible cause

Three way catalyst (manifold)

Exhaust tube
Intake air leaks
Fuel injector
Fuel injector leaks
Spark plug
Improper ignition timing

DTC CONFIRMATION PROCEDURE

1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 7.

2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE-I

1.
2.
3.
4.
5.
6.
7.

With CONSULT-III
Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.

Revision: 2007 June

EC-272

G37 Coupe

P0420, P0430 THREE WAY CATALYST FUNCTION

[VQ37VHR]
< COMPONENT DIAGNOSIS >
8. Make sure that COOLAN TEMP/S indicates more than 70C (158F).
If not, warm up engine and go to next step when COOLAN TEMP/S indication reaches to 70C (158F). A
9. Open engine hood.
10. Select DTC & SRT CONFIRMATION then SRT WORK SUPPORT mode with CONSULT-III.
11. Rev engine up to about 2,000 rpm and hold it for 3 consecutive minutes then release the accelerator
EC
pedal completely.
12. Check the indication of CATALYST.
Which is displayed on CONSULT-III screen?
C
CMPLT >> GO TO 6.
INCMP >> GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE-II

1.
2.

Wait 5 seconds at idle.

Rev engine up to about 2,000 rpm and maintain it until INCMP of CATALYST changes to CMPLT (It
will take approximately 5 minutes).
Does the indication change to CMPLT?
YES >> GO TO 6.
NO
>> GO TO 5.

5.PERFORM DTC CONFIRMATION PROCEDURE AGAIN

1.
2.

Stop engine and cool it down to less than 70C (158F).

Perform DTC CONFIRMATION PROCEDURE again.

>> GO TO 3.

6.PERFORM DTC CONFIRMATION PROCEDURE-III

Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-274, "Diagnosis Procedure".
NO
>> INSPECTION END

7.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-273, "Component Function Check".

NOTE:
Use component function check to check the overall function of the three way catalyst (manifold). During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-274, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734100

Without CONSULT-III
Start engine and warm it up to the normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
Let engine idle for 1 minute.
Open engine hood.
Check the voltage between ECM harness connector and ground under the following condition.

1.PERFORM COMPONENT FUNCTION CHECK

1.
2.
3.
4.
5.
6.
7.
8.

Revision: 2007 June

EC-273

G37 Coupe

P0420, P0430 THREE WAY CATALYST FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

ECM
Connector

P0420
F102
P0430

Terminal
76
[HO2S2 (bank 1)]
80
[HO2S2 (bank 2)]

Ground

Condition

Voltage

Ground

Keeping engine speed at 2500 rpm

constant under no load

The voltage fluctuation cycle takes more

than 5 seconds.
1 cycle: 0.6 - 1.0 0 - 0.3 0.6 - 1.0

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-274, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734101

1.CHECK EXHAUST SYSTEM

Visually check exhaust tubes and muffler for dent.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace.

2.CHECK EXHAUST GAS LEAK

1.
2.

Start engine and run it at idle.

Listen for an exhaust gas leak before the three way catalyst 1.

PBIB1922E

Is exhaust gas leak detected?

YES >> Repair or replace.
NO
>> GO TO 3.

3.CHECK INTAKE AIR LEAK

Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES >> Repair or replace.
NO
>> GO TO 4.

4.CHECK IDLE SPEED AND IGNITION TIMING

For procedure, refer to EC-13, "BASIC INSPECTION : Special Repair Requirement".
For specification, refer to EC-606, "Idle Speed" and EC-606, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Follow the EC-13, "BASIC INSPECTION : Special Repair Requirement".

5.CHECK FUEL INJECTORS

1.
2.

Stop engine and then turn ignition switch ON.

Check the voltage between ECM harness connector and ground.

Revision: 2007 June

EC-274

G37 Coupe

P0420, P0430 THREE WAY CATALYST FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM
Connector

Terminal

Ground

Voltage

81

EC

82
F102

85
86

Ground

Battery voltage

89
90

Is the inspection result normal?

YES >> GO TO 6.
NO
>> Perform EC-487, "Diagnosis Procedure".

6.CHECK FUNCTION OF IGNITION COIL-I

CAUTION:
Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse (1) in IPDM E/R (2) to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following procedure.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel
pressure.
5. Turn ignition switch OFF.
6. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be
checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
11. Crank engine for about 3 seconds, and check whether spark is
generated between the spark plug and the grounded metal portion.

I
JMBIA0021ZZ

Spark should be generated.

CAUTION:
Do not approach to the spark plug and the ignition coil
JMBIA0066GB
within 50 cm (19.7 in). Be careful not to get an electrical
shock while checking, because the electrical discharge
voltage becomes 20kV or more.
It might cause to damage the ignition coil if the gap of more than 17 mm (0.66 in) is taken.
NOTE:
When the gap is less than 13 mm (0.52 in), the spark might be generated even if the coil is malfunctioning.
Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 7.

7.CHECK FUNCTION OF IGNITION COIL-II

1.
2.

Turn ignition switch OFF.

Disconnect spark plug and connect a known-good spark plug.

Revision: 2007 June

EC-275

G37 Coupe

P0420, P0430 THREE WAY CATALYST FUNCTION

[VQ37VHR]
< COMPONENT DIAGNOSIS >
3. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and
the grounded metal portion.
Spark should be generated.
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Check ignition coil, power transistor and their circuits. Refer to EC-498, "Diagnosis Procedure".

8.CHECK SPARK PLUG

Check the initial spark plug for fouling, etc.
Is the inspection result normal?
YES >> Replace spark plug(s) with standard type one(s). For
spark plug type, refer to EM-16, "Inspection".
NO
>> Repair or clean spark plug. Then GO TO 9.

SEF156I

9.CHECK FUNCTION OF IGNITION COIL-III

1.
2.

Reconnect the initial spark plugs.

Crank engine for about three seconds, and recheck whether spark is generated between the spark plug
and the grounded portion.
Spark should be generated.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace spark plug(s) with standard type one(s). For spark plug type, refer to EM-15, "Removal
and Installation".

10.CHECK FUEL INJECTOR

1.
2.

Turn ignition switch OFF.

Remove fuel injector assembly.
Refer to EM-36, "Removal and Installation".
Keep fuel hose and all fuel injectors connected to fuel tube.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.
Does fuel drip from fuel injector?
YES >> Replace the fuel injector(s) from which fuel is dripping.
NO
>> GO TO 11.

11.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the trouble fixed?
YES >> INSPECTION END
NO
>> Replace three way catalyst assembly.

Revision: 2007 June

EC-276

G37 Coupe

P0441 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0441 EVAP CONTROL SYSTEM

DTC Logic

INFOID:0000000001734102

DTC DETECTION LOGIC

EC

NOTE:
If DTC P0441 is displayed with other DTC such as P2122, P2123, P2127, P2128 or P2138, first perform
trouble diagnosis for other DTC.
In this evaporative emission (EVAP) control system, purge flow occurs during non-closed throttle conditions.
Purge volume is related to air intake volume. Under normal purge conditions (non-closed throttle), the EVAP
canister purge volume control solenoid valve is open to admit purge flow. Purge flow exposes the EVAP control system pressure sensor to intake manifold vacuum.
Under normal conditions (non-closed throttle), sensor output voltage indicates if pressure drop and purge flow
are adequate. If not, a malfunction is determined.

PBIB1026E

DTC No.

P0441

Trouble diagnosis name

EVAP control system incorrect purge flow

DTC detecting condition

Possible cause

EVAP control system does not operate properly, EVAP control system has a leak between intake manifold and EVAP control system
pressure sensor.

EVAP canister purge volume control solenoid valve stuck closed

EVAP control system pressure sensor
and the circuit
Loose, disconnected or improper connection of rubber tube
Blocked rubber tube
Cracked EVAP canister
EVAP canister purge volume control solenoid valve circuit
Accelerator pedal position sensor
Blocked purge port
EVAP canister vent control valve

DTC CONFIRMATION PROCEDURE

1.INSPECTION START

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 6.

2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
Revision: 2007 June

EC-277

G37 Coupe

P0441 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Always perform test at a temperature of 5C (41F) or more.

[VQ37VHR]

>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE-I

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Start engine and let it idle for at least 70 seconds.
Select PURG FLOW P0441 of EVAPORATIVE SYSTEM in DTC WORK SUPPORT mode with CONSULT-III.
7. Touch START.
Is COMPLETED displayed on CONSULT-III screen?
YES >> GO TO 5.
NO
>> GO TO 4.

1.
2.
3.
4.
5.
6.

4.PERFORM DTC CONFIRMATION PROCEDURE-II

When the following conditions are met, TESTING will be displayed on the CONSULT-III screen. Maintain the
conditions continuously until TESTING changes to COMPLETED. (It will take at least 35 seconds.)
Selector lever

Suitable position

VHCL SPEED SE

32 - 120 km/h (20 - 75 mph)

ENG SPEED

500 - 3,000 rpm

B/FUEL SCHDL

1.3 - 9.0 msec

COOLAN TEMP/S

More than 0C (32F)

CAUTION:
Always drive vehicle at a safe speed.
Is COMPLETED displayed on CONSULT-III screen?
YES >> GO TO 5.
NO
>> Perform DTC CONFIRMATION PROCEDURE again. GO TO 3.

5.PERFORM DTC CONFIRMATION PROCEDURE-III

Touch SELF-DIAG RESULTS.
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-279, "Diagnosis Procedure".

6.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-278, "Component Function Check".
NOTE:
Use component function check to check the overall monitoring function of the EVAP control system purge flow
monitoring. During this check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-279, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734103

1.PERFORM COMPONENT FUNCTION CHECK

1.

Without CONSULT-III
Lift up drive wheels.

Revision: 2007 June

EC-278

G37 Coupe

P0441 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
2. Start engine (VDC switch OFF) and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and wait at least 70 seconds.
7. Set voltmeter probes to ECM harness connector and ground as follows.
ECM

EC

Ground

Connector

Terminal

M107

102
(EVAP control system pressure sensor signal)

8.
9.

[VQ37VHR]

Ground

Check EVAP control system pressure sensor value at idle speed and note it.
Establish and maintain the following conditions for at least 1 minute.
E

Air conditioner switch

ON

Headlamp switch

ON

Rear window defogger switch

ON

Engine speed

Approx. 3,000 rpm

Gear position

Any position other than P, N or R

10. Verify that EVAP control system pressure sensor value stays 0.1V less than the value at idle speed (measured at step 8) for at least 1 second.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-279, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734104

1.CHECK EVAP CANISTER

J

1. Turn ignition switch OFF.

2. Check EVAP canister for cracks.
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 2.
YES-2 >> Without CONSULT-III: GO TO 3.
NO
>> Replace EVAP canister.

2.CHECK PURGE FLOW

With CONSULT-III
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
2. Start engine and let it idle.
3. Select PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III.
4. Touch Qd and Qu on CONSULT-III screen to adjust PURG VOL CONT/V opening and check vacuum
existence.
1.

PURG VOL CONT/V

Existed

0%

Not existed

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 4.

3.CHECK PURGE FLOW

1.

Without CONSULT-III
Start engine and warm it up to normal operating temperature.

Revision: 2007 June

Vacuum

100%

EC-279

G37 Coupe

P0441 EVAP CONTROL SYSTEM

[VQ37VHR]
< COMPONENT DIAGNOSIS >
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port and install vacuum gauge. For the location of EVAP service port, refer to EC-80, "System Diagram".
4. Start engine and let it idle.
Do not depress accelerator pedal even slightly.
5. Check vacuum gauge indication before 60 seconds passed after starting engine.
Vacuum should not exist.
6.

Revving engine up to 2,000rpm after 100 seconds passed after starting engine.
Vacuum should exist.

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 4.

4.CHECK EVAP PURGE LINE

1.
2.

Turn ignition switch OFF.

Check EVAP purge line for improper connection or disconnection.
Refer to EC-80, "System Diagram".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair it.

5.CHECK EVAP PURGE HOSE AND PURGE PORT

1.
2.

Disconnect purge hoses connected to EVAP service port A and

EVAP canister purge volume control solenoid valve B.
Blow air into each hose and EVAP purge port C.

SEF367U

3. Check that air flows freely.

Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 6.
YES-2 >> Without CONSULT-III: GO TO 7.
NO
>> Repair or clean hoses and/or purge port.

SEF368U

6.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

With CONSULT-III
Start engine.
Perform PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III. Check that engine speed varies according to the valve opening.
Does engine speed vary according to the valve opening?
YES >> GO TO 8.
NO
>> GO TO 7.
1.
2.

Revision: 2007 June

EC-280

G37 Coupe

P0441 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

7.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

Refer to EC-291, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace EVAP canister purge volume control solenoid valve.

EC

8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR

1.
2.

Disconnect EVAP control system pressure sensor harness connector.

Check connectors for water.

Water should not exist.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace EVAP control system pressure sensor.

9.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR FUNCTION

Refer to EC-307, "DTC Logic" for DTC P0452, EC-312, "DTC Logic" for DTC P0453.
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace EVAP control system pressure sensor.

10.CHECK RUBBER TUBE FOR CLOGGING

1. Disconnect rubber tube connected to EVAP canister vent control valve.
2. Check the rubber tube for clogging.
Is the inspection result normal?
YES >> GO TO 11.
NO
>> Clean the rubber tube using an air blower.

11.CHECK EVAP CANISTER VENT CONTROL VALVE

J

Refer to EC-298, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 12.
NO
>> Replace EVAP canister vent control valve.

12.CHECK EVAP PURGE LINE

Inspect EVAP purge line (pipe and rubber tube). Check for evidence of leaks.
Refer to EC-80, "System Diagram".
Is the inspection result normal?
YES >> GO TO 13.
NO
>> Replace it.

13.CLEAN EVAP PURGE LINE

N

Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 14.

14.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Revision: 2007 June

EC-281

G37 Coupe

P0442 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0442 EVAP CONTROL SYSTEM

DTC Logic

INFOID:0000000001734105

DTC DETECTION LOGIC

NOTE:
If DTC P0442 is displayed with DTC P0456, first perform the trouble diagnosis for DTC P0456. Refer to
EC-324, "DTC Logic".
This diagnosis detects leaks in the EVAP purge line using engine intake manifold vacuum.
If pressure does not increase, the ECM will check for leaks in the line between the fuel tank and EVAP canister
purge volume control solenoid valve, under the following Vacuum test conditions.
The EVAP canister vent control valve is closed to shut the EVAP purge line off. The EVAP canister purge volume control solenoid valve will then be opened to depressurize the EVAP purge line using intake manifold
vacuum. After this occurs, the EVAP canister purge volume control solenoid valve will be closed.

PBIB1026E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0442

EVAP control system

small leak detected
(negative pressure)

EVAP control system has a leak, EVAP

control system does not operate properly.

Incorrect fuel tank vacuum relief valve

Incorrect fuel filler cap used
Fuel filler cap remains open or fails to close.
Foreign matter caught in fuel filler cap.
Leak is in line between intake manifold and EVAP
canister purge volume control solenoid valve.
Foreign matter caught in EVAP canister vent control valve.
EVAP canister or fuel tank leaks
EVAP purge line (pipe and rubber tube) leaks
EVAP purge line rubber tube bent
Loose or disconnected rubber tube
EVAP canister vent control valve and the circuit
EVAP canister purge volume control solenoid
valve and the circuit
Fuel tank temperature sensor
O-ring of EVAP canister vent control valve is
missing or damaged
EVAP canister is saturated with water
EVAP control system pressure sensor
Fuel level sensor and the circuit
Refueling EVAP vapor cut valve
ORVR system leaks

CAUTION:
Use only a genuine NISSAN fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the
MIL may come on.
If the fuel filler cap is not tightened properly, the MIL may come on.
Revision: 2007 June

EC-282

G37 Coupe

P0442 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
Use only a genuine NISSAN rubber tube as a replacement.

[VQ37VHR]
A

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct- EC
ing the next test.
TESTING CONDITION:
Perform DTC WORK SUPPORT when the fuel level is between 1/4 and 3/4 full, and vehicle is placed C
on flat level surface.
Always perform test at a temperature of 0 to 30C (32 to 86F).
NOTE:
Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve D
properly.
Do you have CONSULT-III?
E
YES >> GO TO 2.
NO
>> GO TO 3.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
4. Make sure that the following conditions are met.
COOLAN TEMP/S: 0 - 70C (32 - 158F)
INT/A TEMP SE: 0 - 30C (32 - 86F)
5. Select EVAP SML LEAK P0442/P1442 of EVAPORATIVE SYSTEM in DTC WORK SUPPORT mode
with CONSULT-III.
Follow the instruction displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on the CONSULT-III screen, go to
EC-13, "BASIC INSPECTION : Special Repair Requirement".
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-283, "Diagnosis Procedure".

3.PERFORM DTC CONFIRMATION PROCEDURE

With GST
NOTE:
Be sure to read the explanation of Driving Pattern in EC-557, "How to Set SRT Code" before driving vehicle.
1. Start engine.
2. Drive vehicle according to Driving Pattern,
3. Stop vehicle.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON.
6. Turn ignition switch OFF and wait at least 10 seconds.
7. Check 1st trip DTC.
Is 1st trip DTC displayed?
YES-1 >> P0441: Go to EC-279, "Diagnosis Procedure".
YES-2 >> P0442: Go to EC-283, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734106

1.CHECK FUEL FILLER CAP DESIGN

1.

Turn ignition switch OFF.

Revision: 2007 June

EC-283

G37 Coupe

P0442 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
2. Check for genuine NISSAN fuel filler cap design.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Replace with genuine NISSAN fuel filler cap.

[VQ37VHR]

SEF915U

2.CHECK FUEL FILLER CAP INSTALLATION

Check that the cap is tightened properly by rotating the cap clockwise.
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Open fuel filler cap, then clean cap and fuel filler neck threads using air blower. Retighten until
ratcheting sound is heard.

3.CHECK FUEL FILLER CAP FUNCTION

Check for air releasing sound while opening the fuel filler cap.
Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.CHECK FUEL TANK VACUUM RELIEF VALVE

Refer to EC-287, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace fuel filler cap with a genuine one.

5.CHECK FOR EVAP LEAK

Refer to EC-602, "Inspection".
Is there any leak in EVAP line?
YES >> Repair or replace.
NO
>> GO TO 6.

6.CHECK EVAP CANISTER VENT CONTROL VALVE

Check the following.
EVAP canister vent control valve is installed properly.
Refer to EC-604, "Removal and Installation".
EVAP canister vent control valve.
Refer to EC-298, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair or replace EVAP canister vent control valve and O-ring.

7.CHECK IF EVAP CANISTER SATURATED WITH WATER

1.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.

Revision: 2007 June

EC-284

G37 Coupe

P0442 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
2. Check if water will drain from EVAP canister (1).

[VQ37VHR]
A

: EVAP canister vent control valve

Does water drain from the EVAP canister?

YES >> GO TO 8.
NO-1 >> With CONSULT-III: GO TO 10.
NO-2 >> Without CONSULT-III: GO TO 11.

EC

C
PBIB2731E

8.CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 10.
YES-2 >> Without CONSULT-III: GO TO 11.
NO
>> GO TO 9.

9.DETECT MALFUNCTIONING PART

Check the following.

EVAP canister for damage
EVAP hose between EVAP canister and vehicle frame for clogging or poor connection

>> Repair hose or replace EVAP canister.

10.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

With CONSULT-III
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
2. Start engine and let it idle.
3. Select PURG VOL CONT/V in ACTIVE TEST mode.
4. Touch Qu on CONSULT-III screen to increase PURG VOL CONT/V opening to 100%.
5. Check vacuum hose for vacuum.
1.

Vacuum should exist.

Is the inspection result normal?

YES >> GO TO 13.
NO
>> GO TO 12.

11.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

Without CONSULT-III
Start engine and warm it up to normal operating temperature.
Stop engine.
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
1.
2.
3.

Vacuum should exist.

Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.

12.CHECK VACUUM HOSE

Check vacuum hoses for clogging or disconnection. Refer to EC-80, "System Diagram".
Revision: 2007 June

EC-285

G37 Coupe

P0442 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 13.
NO
>> Repair or reconnect the hose.

13.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

Refer to EC-291, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 14.
NO
>> Replace EVAP canister purge volume control solenoid valve.

14.CHECK FUEL TANK TEMPERATURE SENSOR

Refer to EC-242, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace fuel level sensor unit.

15.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 16.
NO
>> Replace EVAP control system pressure sensor.

16.CHECK EVAP PURGE LINE

Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
Refer to EC-80, "System Diagram".
Is the inspection result normal?
YES >> GO TO 17.
NO
>> Repair or reconnect the hose.

17.CLEAN EVAP PURGE LINE

Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 18.

18.CHECK EVAP/ORVR LINE

Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper connection. For location, refer to EC-504, "Description".
Is the inspection result normal?
YES >> GO TO 19.
NO
>> Repair or replace hoses and tubes.

19.CHECK RECIRCULATION LINE

Check recirculation line between filler neck tube and fuel tank for clogging, kink, cracks, looseness and
improper connection.
Is the inspection result normal?
YES >> GO TO 20.
NO
>> Repair or replace hose, tube or filler neck tube.

20.CHECK REFUELING EVAP VAPOR CUT VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

21.CHECK FUEL LEVEL SENSOR

Refer to MWI-55, "Component Inspection".
Is the inspection result normal?
Revision: 2007 June

EC-286

G37 Coupe

P0442 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 22.
NO
>> Replace fuel level sensor unit.

22.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

EC

>> INSPECTION END

Component Inspection

INFOID:0000000001734107

1.CHECK FUEL TANL VACUUM RELIEF VALVE

1.
2.
3.

Turn ignition switch OFF.

Remove fuel filler cap.
Wipe clean valve housing.

G
SEF445Y

4.

Check valve opening pressure and vacuum.

Pressure:

15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 2.90 psi)

Vacuum:

6.0 to 3.3 kPa (0.061 to 0.034 kg/cm2,

0.87 to 0.48 psi)

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

K
SEF943S

2.REPLACE FUEL FILLER CAP

Replace fuel filler cap.

CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may
come on.
>> INSPECTION END

Revision: 2007 June

EC-287

G37 Coupe

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

Description

INFOID:0000000001734108

The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canister. The EVAP canister purge volume control solenoid valve is
moved by ON/OFF pulses from the ECM. The longer the ON pulse,
the greater the amount of fuel vapor that will flow through the valve.

JMBIA0069ZZ

DTC Logic

INFOID:0000000001734109

DTC DETECTION LOGIC

DTC No.

P0443

Trouble diagnosis name

EVAP canister purge

volume control solenoid
valve

DTC detecting condition

Possible cause

The canister purge flow is detected during the

specified driving conditions, even when EVAP
canister purge volume control solenoid valve is
completely closed.

EVAP control system pressure sensor

EVAP canister purge volume control solenoid valve
(The valve is stuck open.)
EVAP canister vent control valve
EVAP canister
Hoses
(Hoses are connected incorrectly or
clogged.)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Always perform test at a temperature of 5C (41F) or more.
Do you have CONSULT-III
YES >> GO TO 2.
NO
>> GO TO 3.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Select PURG VOL CN/V P1444 of EVAPORATIVE SYSTEM in DTC WORK SUPPORT mode with
CONSULT-III.
7. Touch START.
8. Start engine and let it idle until TESTING on CONSULT-III changes to COMPLETED. (It will take
approximately 10 seconds.)
If TESTING is not displayed after 5 minutes, retry from step 2.
9. Touch SELF-DIAG RESULTS.
Which is displayed on CONSULT-III screen?

1.
2.
3.
4.
5.
6.

Revision: 2007 June

EC-288

G37 Coupe

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

OK
>> INSPECTION END
NG
>> Go to EC-289, "Diagnosis Procedure".

3.PERFORM DTC CONFIRMATION PROCEDURE

With GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and let it idle for at least 20 seconds.
6. Check 1st trip DTC.
Is 1st trip DTC displayed?
YES >> Go to EC-289, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

EC

INFOID:0000000001734110

1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect EVAP canister purge volume control solenoid valve harness connector.
Turn ignition switch ON.
Check the voltage between EVAP canister purge volume control solenoid valve harness connector and
ground.

EVAP canister purge volume control solenoid valve

Connector

Terminal

F7

H
Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 3.
NO
>> GO TO 2.

2.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness connectors M116, F103
Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R
Harness for open or short between EVAP canister purge volume control solenoid valve and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT

FOR OPEN AND SHORT

1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP canister purge volume control solenoid valve harness connector and
ECM harness connector.

O
EVAP canister purge volume control solenoid valve

ECM

Connector

Terminal

Connector

Terminal

F7

F101

21

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Revision: 2007 June

EC-289

G37 Coupe

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

[VQ37VHR]
< COMPONENT DIAGNOSIS >
Check the following.
Harness connectors F104, F105
Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR

1.
2.

Disconnect EVAP control system pressure sensor harness connector.

Check connectors for water.
Water should not exist.

Is the inspection result normal?

YES >> GO TO 6.
NO
>> Replace EVAP control system pressure sensor.

6.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 7.
YES-2 >> Without CONSULT-III: GO TO 8.
NO
>> Replace EVAP control system pressure sensor.

7.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

With CONSULT-III
Turn ignition switch OFF.
Reconnect harness connectors disconnected.
Start engine.
Perform PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III. Check that engine speed varies according to the valve opening.
Does engine speed vary according to the valve opening?
YES >> GO TO 9.
NO
>> GO TO 8.
1.
2.
3.
4.

8.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

Refer to EC-291, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace EVAP canister purge volume control solenoid valve.

9.CHECK RUBBER TUBE FOR CLOGGING

1. Disconnect rubber tube connected to EVAP canister vent control valve.
2. Check the rubber tube for clogging.
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Clean the rubber tube using an air blower.

10.CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to EC-298, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 11.
NO
>> Replace EVAP canister vent control valve.

11.CHECK IF EVAP CANISTER SATURATED WITH WATER

1.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.

Revision: 2007 June

EC-290

G37 Coupe

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

< COMPONENT DIAGNOSIS >
2. Check if water will drain from EVAP canister (1).

[VQ37VHR]
A

: EVAP canister vent control valve

Does water drain from the EVAP canister?

YES >> GO TO 12.
NO
>> GO TO 14.

EC

C
PBIB2731E

12.CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 13.

13.DETECT MALFUNCTIONING PART

G

Check the following.

EVAP canister for damage
EVAP hose between EVAP canister and vehicle frame for clogging or poor connection

>> Repair hose or replace EVAP canister.

14.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734111

1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

1.
2.
3.
4.
5.
6.

With CONSULT-III
Turn ignition switch OFF.
Reconnect all harness connectors disconnected.
Disconnect EVAP purge hoses connected to EVAP canister purge volume control solenoid valve.
Turn ignition switch ON.
Select PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III.
Touch Qd and Qu on CONSULT-III screen to adjust PURG
VOL CONT/V opening and check air passage continuity of
EVAP canister purge volume control solenoid valve under the
following conditions.
Condition
(PURG VOL CONT/V value)

Air passage continuity

between (A) and (B)

100%

Existed

0%

Not existed

P
JMBIA0068ZZ

1.
2.
3.

Without CONSULT-III
Turn ignition switch OFF.
Disconnect EVAP canister purge volume control solenoid valve harness connector.
Disconnect EVAP purge hoses connected to EVAP canister purge volume control solenoid valve.

Revision: 2007 June

EC-291

G37 Coupe

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

[VQ37VHR]
< COMPONENT DIAGNOSIS >
4. Check air passage continuity of EVAP canister purge volume control solenoid valve under the following
conditions.
Condition
12V direct current supply between
terminals 1 and 2
No supply

Air passage continuity

between (A) and (B)
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace EVAP canister purge volume control solenoid valve

Revision: 2007 June

EC-292

G37 Coupe

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID

VALVE
[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID

VALVE
Description

INFOID:0000000001910869

The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canister. The EVAP canister purge volume control solenoid valve is
moved by ON/OFF pulses from the ECM. The longer the ON pulse,
the greater the amount of fuel vapor that will flow through the valve.

EC

E
JMBIA0069ZZ

DTC Logic

INFOID:0000000001734113

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0444

EVAP canister purge volume

control solenoid valve circuit
open

An excessively low voltage signal is sent

to ECM through the valve

Harness or connectors
(The solenoid valve circuit is open or
shorted.)
EVAP canister purge volume control solenoid valve

P0445

EVAP canister purge volume

control solenoid valve circuit
shorted

An excessively high voltage signal is sent

to ECM through the valve

Harness or connectors
(The solenoid valve circuit is shorted.)
EVAP canister purge volume control solenoid valve

DTC CONFIRMATION PROCEDURE

1.CONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm battery voltage is more than 11V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for at least 13 seconds.

2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-293, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

P
INFOID:0000000001734114

1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1.
2.
3.

Turn ignition switch OFF.

Disconnect EVAP canister purge volume control solenoid valve harness connector.
Turn ignition switch ON.

Revision: 2007 June

EC-293

G37 Coupe

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID

VALVE
[VQ37VHR]
< COMPONENT DIAGNOSIS >
4. Check the voltage between EVAP canister purge volume control solenoid valve harness connector and
ground.
EVAP canister purge volume control solenoid valve
Connector

Terminal

F7

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 3.
NO
>> GO TO 2.

2.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness connectors M116, F103
Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R
Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT
FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP canister purge volume control solenoid valve harness connector and
ECM harness connector.
EVAP canister purge volume control solenoid valve

ECM

Continuity

Connector

Terminal

Connector

Terminal

F7

F101

21

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 5.
YES-2 >> Without CONSULT-III: GO TO 6.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F104, F105
Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

With CONSULT-III
Reconnect all harness connectors disconnected.
Start engine.
Perform PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III. Check that engine speed varies according to the valve opening.
Does engine speed vary according to the valve opening?
YES >> GO TO 7.
NO
>> GO TO 6.
1.
2.
3.

6.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

Refer to EC-295, "Component Inspection".
Revision: 2007 June

EC-294

G37 Coupe

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID

VALVE
< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Replace EVAP canister purge volume control solenoid valve.

[VQ37VHR]
A

7.CHECK INTERMITTENT INCIDENT

EC

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001910870

1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

1.
2.
3.
4.
5.
6.

With CONSULT-III
Turn ignition switch OFF.
Reconnect all harness connectors disconnected.
Disconnect EVAP purge hoses connected to EVAP canister purge volume control solenoid valve.
Turn ignition switch ON.
Select PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III.
Touch Qd and Qu on CONSULT-III screen to adjust PURG
VOL CONT/V opening and check air passage continuity of
EVAP canister purge volume control solenoid valve under the
following conditions.
Condition
(PURG VOL CONT/V value)

Air passage continuity

between (A) and (B)

100%

Existed

0%

Not existed

I
JMBIA0068ZZ

1.
2.
3.
4.

Without CONSULT-III
Turn ignition switch OFF.
Disconnect EVAP canister purge volume control solenoid valve harness connector.
Disconnect EVAP purge hoses connected to EVAP canister purge volume control solenoid valve.
Check air passage continuity of EVAP canister purge volume control solenoid valve under the following
conditions.
Condition

12V direct current supply between

terminals 1 and 2
No supply

Air passage continuity

between (A) and (B)
Existed

Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace EVAP canister purge volume control solenoid valve

Revision: 2007 June

EC-295

G37 Coupe

P0447 EVAP CANISTER VENT CONTROL VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0447 EVAP CANISTER VENT CONTROL VALVE

Description

INFOID:0000000001734116

The EVAP canister vent control valve is located on the EVAP canister and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal
the vent is necessary for the on board diagnosis of other evaporative
emission control system components.
This solenoid valve is used only for diagnosis, and usually remains
opened.
When the vent is closed, under normal purge conditions, the evaporative emission control system is depressurized and allows EVAP
Control System diagnosis.

PBIB1263E

DTC Logic

INFOID:0000000001734117

DTC DETECTION LOGIC

DTC No.
P0447

Trouble diagnosis name

EVAP canister vent control valve circuit open

DTC detecting condition

An improper voltage signal is sent to ECM
through EVAP canister vent control valve.

Possible cause
Harness or connectors
(The valve circuit is open or shorted.)
EVAP canister vent control valve

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm battery voltage is more than 11V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and wait at least 8 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-296, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734118

1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.CHECK EVAP CANISTER VENT CONTROL VALVE CIRCUIT

1.
2.

With CONSULT-III
Turn ignition switch OFF and then turn ON.
Select VENT CONTROL/V in ACTIVE TEST mode with CONSULT-III.

Revision: 2007 June

EC-296

G37 Coupe

P0447 EVAP CANISTER VENT CONTROL VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

3. Touch ON/OFF on CONSULT-III screen.
4. Check for operating sound of the valve.

Clicking sound should be heard.

EC

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 3.

3.CHECK EVAP CANISTER VENT CONTROL VALVE POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect EVAP canister vent control valve harness connector.
Turn ignition switch ON.
Check the voltage between EVAP canister vent control valve harness connector and ground.

EVAP canister vent control valve

Connector

Terminal

B31

E
Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

H

Check the following.

Harness connectors E3, F1
Harness connectors F103, M116
Harness connectors M7, B1
Harness for open or short between EVAP canister vent control valve and IPDM E/R

>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK EVAP CANISTER VENT CONTROL VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between EVAP canister vent control valve harness connector and ECM harness connector.

L
EVAP canister vent
control valve

ECM

Continuity

Connector

Terminal

Connector

Terminal

B31

M107

121

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors B1, M7
Harness for open or short between EVAP canister vent control valve and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK RUBBER TUBE FOR CLOGGING

1.
2.

Disconnect rubber tube connected to EVAP canister vent control valve.

Check the rubber tube for clogging.

Revision: 2007 June

EC-297

G37 Coupe

P0447 EVAP CANISTER VENT CONTROL VALVE

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Clean the rubber tube using an air blower.

[VQ37VHR]

8.CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to EC-298, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace EVAP canister vent control valve.

9.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734119

1.CHECK EVAP CANISTER VENT CONTROL VALVE-I

1.
2.
3.

Turn ignition switch OFF.

Remove EVAP canister vent control valve from EVAP canister.
Check portion (A) of EVAP canister vent control valve for being
rusted.
Is it rusted?
YES >> Replace EVAP canister vent control valve
NO
>> GO TO 2.

JMBIA0168ZZ

2.CHECK EVAP CANISTER VENT CONTROL VALVE-II

1.
2.
3.
4.

With CONSULT-III
Reconnect harness connectors disconnected.
Turn ignition switch ON.
Perform VENT CONTROL/V in ACTIVE TEST mode.
Check air passage continuity and operation delay time.
Make sure new O-ring is installed properly.

Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

Not existed

OFF

Existed

Operation takes less than 1 second.

Without CONSULT-III
1. Disconnect EVAP canister vent control valve harness connector.
2. Check air passage continuity and operation delay time under the
following conditions.
Make sure new O-ring is installed properly.
Condition

JMBIA0169ZZ

Air passage continuity between (A) and (B)

12V direct current supply between

terminals 1 and 2
OFF

Not existed
Existed

Operation takes less than 1 second.

Is the inspection result normal?

Revision: 2007 June

EC-298

G37 Coupe

P0447 EVAP CANISTER VENT CONTROL VALVE

< COMPONENT DIAGNOSIS >
YES >> GO TO 3.
NO
>> Replace EVAP canister vent control valve

[VQ37VHR]
A

3.CHECK EVAP CANISTER VENT CONTROL VALVE-III

1.
2.
3.

With CONSULT-III
Clean the air passage [portion (A) to (B)] of EVAP canister vent control valve using an air blower.
Perform VENT CONTROL/V in ACTIVE TEST mode.
Check air passage continuity and operation delay time.
Make sure new O-ring is installed properly.

Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

Not existed

OFF

Existed

EC

Operation takes less than 1 second.

Without CONSULT-III
1. Clean the air passage [portion (A) to (B)] of EVAP canister vent
control valve using an air blower.
2. Check air passage continuity and operation delay time under the
following conditions.
Make sure new O-ring is installed properly.

JMBIA0169ZZ

G
Condition

Air passage continuity between (A) and (B)

12V direct current supply between

terminals 1 and 2
OFF

Not existed

Existed

Operation takes less than 1 second.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace EVAP canister vent control valve

Revision: 2007 June

EC-299

G37 Coupe

P0448 EVAP CANISTER VENT CONTROL VALVE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0448 EVAP CANISTER VENT CONTROL VALVE

Description

INFOID:0000000001910881

The EVAP canister vent control valve is located on the EVAP canister and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal
the vent is necessary for the on board diagnosis of other evaporative
emission control system components.
This solenoid valve is used only for diagnosis, and usually remains
opened.
When the vent is closed, under normal purge conditions, the evaporative emission control system is depressurized and allows EVAP
Control System diagnosis.

DTC Logic

PBIB1263E

INFOID:0000000001734121

DTC DETECTION LOGIC

DTC No.

P0448

Trouble diagnosis name

EVAP canister vent control valve close

DTC detecting condition

EVAP canister vent control valve remains

closed under specified driving conditions.

Possible cause
EVAP canister vent control valve
EVAP control system pressure sensor
and the circuit
Blocked rubber tube to EVAP canister
vent control valve
EVAP canister is saturated with water

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
1. Turn ignition switch ON and wait at least 5 seconds.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
4. Start engine and let it idle for at least 1 minute.
5. Repeat next procedures five times.
Increase the engine speed up to 3,000 to 3,500 rpm and keep it for 2 minutes.
Never exceed 2 minutes.
Fully released accelerator pedal and keep engine idle for about 5 seconds.
6. Repeat next procedure 27 times.
Quickly increase the engine speed up to 3,000 to 3,500 rpm or more and keep it for 25 to 30 seconds.

Revision: 2007 June

EC-300

G37 Coupe

P0448 EVAP CANISTER VENT CONTROL VALVE

< COMPONENT DIAGNOSIS >
Fully released accelerator pedal and keep engine idle for at least 35 seconds.

[VQ37VHR]
A

EC

C
PBIB0972E

7.

Check 1st trip DTC.

With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-301, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734122

1.CHECK RUBBER TUBE

1. Turn ignition switch OFF.
2. Disconnect rubber tube connected to EVAP canister vent control valve.
3. Check the rubber tube for clogging.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Clean rubber tube using an air blower.

2.CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to EC-302, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Replace EVAP canister vent control valve.

3.CHECK IF EVAP CANISTER SATURATED WITH WATER

1.
2.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
Check if water will drain from the EVAP canister (1).
2

: EVAP canister vent control valve

Does water drain from EVAP canister?

YES >> GO TO 4.
NO
>> GO TO 6.

PBIB2731E

4.CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Revision: 2007 June

EC-301

G37 Coupe

P0448 EVAP CANISTER VENT CONTROL VALVE

< COMPONENT DIAGNOSIS >
Check the following.
EVAP canister for damage
EVAP hose between EVAP canister and vehicle frame for clogging or poor connection

[VQ37VHR]

>> Repair hose or replace EVAP canister.

6.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR

1.
2.

Disconnect EVAP control system pressure sensor harness connector.

Check connectors for water.
Water should not exist.

Is the inspection result normal?

YES >> GO TO 7.
NO
>> Replace EVAP control system pressure sensor.

7.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace EVAP control system pressure sensor.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910882

1.CHECK EVAP CANISTER VENT CONTROL VALVE-I

1.
2.
3.

Turn ignition switch OFF.

Remove EVAP canister vent control valve from EVAP canister.
Check portion (A) of EVAP canister vent control valve for being
rusted.
Is it rusted?
YES >> Replace EVAP canister vent control valve
NO
>> GO TO 2.

JMBIA0168ZZ

2.CHECK EVAP CANISTER VENT CONTROL VALVE-II

1.
2.
3.

With CONSULT-III
Reconnect harness connectors disconnected.
Turn ignition switch ON.
Perform VENT CONTROL/V in ACTIVE TEST mode.

Revision: 2007 June

EC-302

G37 Coupe

P0448 EVAP CANISTER VENT CONTROL VALVE

< COMPONENT DIAGNOSIS >
4. Check air passage continuity and operation delay time.
Make sure new O-ring is installed properly.
Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

Not existed

OFF

Existed

[VQ37VHR]
A

EC

Operation takes less than 1 second.

Without CONSULT-III
1. Disconnect EVAP canister vent control valve harness connector.
2. Check air passage continuity and operation delay time under the
following conditions.
Make sure new O-ring is installed properly.
Condition

JMBIA0169ZZ

Air passage continuity between (A) and (B)

12V direct current supply between

terminals 1 and 2

Not existed

OFF

Existed

Operation takes less than 1 second.

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Replace EVAP canister vent control valve

3.CHECK EVAP CANISTER VENT CONTROL VALVE-III

1.
2.
3.

With CONSULT-III
Clean the air passage [portion (A) to (B)] of EVAP canister vent control valve using an air blower.
Perform VENT CONTROL/V in ACTIVE TEST mode.
Check air passage continuity and operation delay time.
Make sure new O-ring is installed properly.

J
Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

Not existed

OFF

Existed

Operation takes less than 1 second.

Without CONSULT-III
1. Clean the air passage [portion (A) to (B)] of EVAP canister vent
control valve using an air blower.
2. Check air passage continuity and operation delay time under the
following conditions.
Make sure new O-ring is installed properly.
Condition

L
JMBIA0169ZZ

Air passage continuity between (A) and (B)

12V direct current supply between

terminals 1 and 2
OFF

Not existed

Existed

Operation takes less than 1 second.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace EVAP canister vent control valve

Revision: 2007 June

EC-303

G37 Coupe

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

Description

INFOID:0000000001734124

The EVAP control system pressure sensor detects pressure in the

purge line. The sensor output voltage to the ECM increases as pressure increases.

PBIB3370E

DTC Logic

INFOID:0000000001734125

DTC DETECTION LOGIC

DTC No.

P0451

Trouble diagnosis name

EVAP control system

pressure sensor performance

DTC detecting condition

Possible cause

ECM detects a sloshing signal from the EVAP

control system pressure sensor

Harness or connectors
(EVAP control system pressure sensor
circuit is shorted.)
[CKP sensor (POS) circuit is shorted.]
(APP sensor 2 circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
(Brake booster pressure sensor circuit is
shorted)
EVAP control system pressure sensor
Crankshaft position sensor (POS)
Accelerator pedal position sensor
Refrigerant pressure sensor
Brake booster pressure sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.

Turn ignition switch OFF and wait at least 10 seconds.

Start engine and wait at least 40 seconds.
NOTE:
Do not depress accelerator pedal even slightly.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-304, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734126

1.CHECK GROUND CONNECTION

Revision: 2007 June

EC-304

G37 Coupe

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

< COMPONENT DIAGNOSIS >
1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

[VQ37VHR]
A

EC

2.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR FOR WATER

1.
2.

Disconnect EVAP control system pressure sensor harness connector.

Check sensor harness connector for water.

Water should not exist.

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair or replace harness connector.

3.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT

1.
2.

Turn ignition switch ON.

Check the voltage between EVAP control system pressure sensor harness connector and ground.
EVAP control system
pressure sensor

Connector

Terminal

B30

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 4.

4.CHECK SENSOR POWER SUPPLY CIRCUIT

Check harness for short to power and short to ground, between the following terminals.

J
ECM
Connector
F101

M107

Sensor

Terminal

Name

45

Brake booster pressure sensor

46

CKP sensor (POS)

Connector

Terminal

E48

F2

103

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

Is the inspection result normal?

YES >> GO TO 5.
NO
>> Repair short to ground or short to power in harness or connectors.

5.CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-267, "Component Inspection".)
Brake booster pressure sensor (Refer to EC-352, "Component Inspection".)
Refrigerant pressure sensor (Refer to HAC-85, "Diagnosis Procedure".)
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace malfunctioning component.

6.CHECK APP SENSOR

Refer to EC-460, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
Revision: 2007 June

EC-305

G37 Coupe

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> GO TO 7.

7.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly

Go to EC-460, "Special Repair Requirement".
>> INSPECTION END

8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Replace EVAP control system pressure sensor.

9.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734127

1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister.
Always replace O-ring with a new one.
Install a vacuum pump to EVAP control system pressure sensor.
Turn ignition switch ON and check output voltage between ECM harness connector and ground under the
following conditions.
ECM

Connector

Terminal

M107

102

Ground

Ground

Condition
[Applied vacuum kPa (kg/cm2, psi)]

Voltage

Not applied

1.8 - 4.8V

-26.7 (-0.272, -3.87)

2.1 to 2.5V lower than above value

CAUTION:
Always calibrate the vacuum pump gauge when using it.
Do not apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or pressure over 101.3 kPa (1.033 kg/
cm2, 14.69 psi).
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace EVAP control system pressure sensor

Revision: 2007 June

EC-306

G37 Coupe

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR

Description

A
INFOID:0000000001910884

The EVAP control system pressure sensor detects pressure in the

purge line. The sensor output voltage to the ECM increases as pressure increases.

EC

PBIB3370E

DTC Logic

INFOID:0000000001734129

DTC DETECTION LOGIC

DTC No.

P0452

Trouble diagnosis name

EVAP control system

pressure sensor low input

DTC detecting condition

An excessively low voltage from the sensor is

sent to ECM.

Possible cause
Harness or connectors
(EVAP control system pressure sensor
circuit is open or shorted.)
[CKP sensor (POS) circuit is shorted.]
(APP sensor 2 circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
(Brake booster pressure sensor circuit is
shorted)
EVAP control system pressure sensor
Crankshaft position sensor (POS)
Accelerator pedal position sensor
Refrigerant pressure sensor
Brake booster pressure sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Always perform test at a temperature of 5C (41F) or more.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.
5.
6.
7.
8.
9.

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Select DATA MONITOR mode with CONSULT-III.
Make sure that FUEL T/TMP SE is more than 0C (32F).
Start engine and wait at least 20 seconds.
Check 1st trip DTC.

Revision: 2007 June

EC-307

G37 Coupe

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

1.
2.

With GST
Start engine and warm it up to normal operating temperature.
Set voltmeter probes to ECM harness connector and ground as follows.
ECM

Ground

Connector

Terminal

M107

106
(Fuel tank temperature sensor signal)

Ground

3. Make sure that the voltage is less than 4.2V.

4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON.
6. Turn ignition switch OFF and wait at least 10 seconds.
7. Start engine and wait at least 20 seconds.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-308, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734130

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK CONNECTOR
1.
2.

Disconnect EVAP control system pressure sensor harness connector.

Check sensor harness connector for water.
Water should not exist.

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair or replace harness connector.

3.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-I

1.
2.

Turn ignition switch ON.

Check the voltage between EVAP control system pressure sensor harness connector and ground.
EVAP control system
pressure sensor

Connector

Terminal

B30

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 10.
NO
>> GO TO 4.

4.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between EVAP control system pressure sensor harness connector and ECM harness connector.

Revision: 2007 June

EC-308

G37 Coupe

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

EVAP control system
pressure sensor

ECM

Continuity

Connector

Terminal

Connector

Terminal

B30

M107

107

EC

Existed

Is the inspection result normal?

YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

D

Check the following.

Harness connectors M7, B1
Harness for open between ECM and EVAP control system pressure sensor

>> Repair open circuit.

6.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-III

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector

Sensor

Terminal

F101

M107

Name

G
Connector

Terminal

E48

F2

45

Brake booster pressure sensor

46

CKP sensor (POS)

103

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

Is the inspection result normal?

YES >> GO TO 7.
NO
>> Repair short to ground or short to power in harness or connectors.

7.CHECK COMPONENTS

Check the following.

Crankshaft position sensor (POS) (Refer to EC-267, "Component Inspection".)
Brake booster pressure sensor (Refer to EC-352, "Component Inspection".)
Refrigerant pressure sensor (Refer to HAC-85, "Diagnosis Procedure".)
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace malfunctioning component.

8.CHECK APP SENSOR

Refer to EC-460, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> GO TO 9.

9.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly

Go to EC-460, "Special Repair Requirement".

>> INSPECTION END

10.CHECK

EVAP CONTROL SYSTEM PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND

SHORT
1. Turn ignition switch OFF.
Revision: 2007 June

EC-309

G37 Coupe

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP control system pressure sensor harness connector and ECM harness connector.
EVAP control system
pressure sensor

ECM

Continuity

Connector

Terminal

Connector

Terminal

B30

M107

112

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 12.
NO
>> GO TO 11.

11.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors B1, M7
Harness for open or short between EVAP control system pressure sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

12.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND
SHORT
1. Check the continuity between EVAP control system pressure sensor harness connector and ECM harness connector.
EVAP control system
pressure sensor

ECM

Continuity

Connector

Terminal

Connector

Terminal

B30

M107

102

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 13.

13.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors B1, M7
Harness for open or short between EVAP control system pressure sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

14.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-310, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace EVAP control system pressure sensor.

15.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734131

1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Revision: 2007 June

EC-310

G37 Coupe

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Turn ignition switch OFF.
2. Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister. A
Always replace O-ring with a new one.
3. Install a vacuum pump to EVAP control system pressure sensor.
4. Turn ignition switch ON and check output voltage between ECM harness connector and ground under the
EC
following conditions.
ECM
Connector

Terminal

M107

102

Ground

Ground

Condition
[Applied vacuum kPa (kg/cm2, psi)]

Voltage

Not applied

1.8 - 4.8V

-26.7 (-0.272, -3.87)

2.1 to 2.5V lower than above value

CAUTION:
Always calibrate the vacuum pump gauge when using it.
Do not apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or pressure over 101.3 kPa (1.033 kg/
cm2, 14.69 psi).
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace EVAP control system pressure sensor

Revision: 2007 June

EC-311

G37 Coupe

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

Description

INFOID:0000000001910888

The EVAP control system pressure sensor detects pressure in the

purge line. The sensor output voltage to the ECM increases as pressure increases.

PBIB3370E

DTC Logic

INFOID:0000000001734133

DTC DETECTION LOGIC

DTC No.

P0453

Trouble diagnosis name

EVAP control system

pressure sensor high input

DTC detecting condition

Possible cause

An excessively high voltage from the sensor is

sent to ECM.

Harness or connectors
(EVAP control system pressure sensor
circuit is open or shorted.)
[CKP sensor (POS) circuit is shorted.]
(APP sensor 2 circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
(Brake booster pressure sensor circuit is
shorted)
EVAP control system pressure sensor
Crankshaft position sensor (POS)
Accelerator pedal position sensor
Refrigerant pressure sensor
Brake booster pressure sensor
EVAP canister vent control valve
EVAP canister
Rubber hose from EVAP canister vent
control valve to vehicle frame

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Always perform test at a temperature of 5C (41F) or more.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.
5.
6.

With CONSULT-III
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Select DATA MONITOR mode with CONSULT-III.

Revision: 2007 June

EC-312

G37 Coupe

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

< COMPONENT DIAGNOSIS >
7. Make sure that FUEL T/TMP SE is more than 0C (32F).
8. Start engine and wait at least 20 seconds.
9. Check 1st trip DTC.
With GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes to ECM harness connector and ground as follows.
ECM

[VQ37VHR]
A

EC

Ground

Connector

Terminal

M107

106
(Fuel tank temperature sensor signal)

Ground

3. Make sure that the voltage is less than 4.2V.

4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON.
6. Turn ignition switch OFF and wait at least 10 seconds.
7. Start engine and wait at least 20 seconds.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-313, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

G
INFOID:0000000001734134

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK CONNECTOR

1.
2.

Disconnect EVAP control system pressure sensor harness connector.

Check sensor harness connector for water.

Water should not exist.

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace harness connector.

3.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT

1.
2.

Turn ignition switch ON.

Check the voltage between EVAP control system pressure sensor harness connector and ground.
N

EVAP control system pressure sensor

Connector

Terminal

B30

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 10.
NO
>> GO TO 4.

4.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between EVAP control system pressure sensor harness connector and ECM harness connector.

Revision: 2007 June

EC-313

G37 Coupe

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

EVAP control system pressure sensor

ECM

Connector

Terminal

Connector

Terminal

B30

M107

107

Continuity
Existed

Is the inspection result normal?

YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M7, B1
Harness for open between ECM and EVAP control system pressure sensor
>> Repair open circuit.

6.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-III

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector

Sensor

Terminal

F101

M107

Name

Connector

Terminal

E48

45

Brake booster pressure sensor

46

CKP sensor (POS)

103

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

F2

Is the inspection result normal?

YES >> GO TO 7.
NO
>> Repair short to ground or short to power in harness or connectors.

7.CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-267, "Component Inspection".)
Brake booster pressure sensor (Refer to EC-352, "Component Inspection".)
Refrigerant pressure sensor (Refer to HAC-85, "Diagnosis Procedure".)
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace malfunctioning component.

8.CHECK APP SENSOR

Refer to EC-460, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 20.
NO
>> GO TO 9.

9.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly

Go to EC-460, "Special Repair Requirement".
>> INSPECTION END

10.CHECK

EVAP CONTROL SYSTEM PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
Revision: 2007 June

EC-314

G37 Coupe

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
3. Check the continuity between EVAP control system pressure sensor harness connector and ECM harness connector.
EVAP control system pressure sensor

ECM

Connector

Terminal

Connector

Terminal

B30

M107

112

Continuity

EC

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 12.
NO
>> GO TO 11.

11.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors B1, M7
Harness for open or short between EVAP control system pressure sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

12.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND
SHORT
1. Check the continuity between EVAP control system pressure sensor harness connector and ECM harness connector.

H
EVAP control system pressure sensor

ECM

Connector

Terminal

Connector

Terminal

B30

M107

102

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 13.

13.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors B1, M7
Harness for open or short between EVAP control system pressure sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

14.CHECK RUBBER TUBE

1. Disconnect rubber tube connected to EVAP canister vent control valve.

2. Check the rubber tube for clogging.
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Clean the rubber tube using an air blower, repair or replace rubber tube.

15.CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to EC-298, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 16.
NO
>> Replace EVAP canister vent control valve.

16.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-316, "Component Inspection".
Is the inspection result normal?
Revision: 2007 June

EC-315

G37 Coupe

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 17.
NO
>> Replace EVAP control system pressure sensor.

17.CHECK IF EVAP CANISTER SATURATED WITH WATER

1.
2.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
Check if water will drain from the EVAP canister (1).
2

: EVAP canister vent control valve

Does water drain from EVAP canister?

YES >> GO TO 18.
NO
>> GO TO 20.

PBIB2731E

18.CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES >> GO TO 20.
NO
>> GO TO 19.

19.DETECT MALFUNCTIONING PART

Check the following.
EVAP canister for damage
EVAP hose between EVAP canister and vehicle frame for clogging or poor connection
>> Repair hose or replace EVAP canister.

20.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734135

1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister.
Always replace O-ring with a new one.
Install a vacuum pump to EVAP control system pressure sensor.
Turn ignition switch ON and check output voltage between ECM harness connector and ground under the
following conditions.
ECM

Connector

Terminal

M107

102

Ground

Ground

Condition
[Applied vacuum kPa (kg/cm2, psi)]

Voltage

Not applied

1.8 - 4.8V

-26.7 (-0.272, -3.87)

2.1 to 2.5V lower than above value

CAUTION:
Always calibrate the vacuum pump gauge when using it.
Do not apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or pressure over 101.3 kPa (1.033 kg/
cm2, 14.69 psi).
Revision: 2007 June

EC-316

G37 Coupe

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace EVAP control system pressure sensor

[VQ37VHR]
A

EC

Revision: 2007 June

EC-317

G37 Coupe

P0455 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0455 EVAP CONTROL SYSTEM

DTC Logic

INFOID:0000000001734136

DTC DETECTION LOGIC

This diagnosis detects a very large leak (fuel filler cap fell off etc.) in EVAP system between the fuel tank and
EVAP canister purge volume control solenoid valve.

PBIB1026E

DTC No.

P0455

Trouble diagnosis name

EVAP control system

gross leak detected

DTC detecting condition

Possible cause

EVAP control system has a very large leak such

as fuel filler cap fell off, EVAP control system
does not operate properly.

Fuel filler cap remains open or fails to

close.
Incorrect fuel tank vacuum relief valve
Incorrect fuel filler cap used
Foreign matter caught in fuel filler cap.
Leak is in line between intake manifold
and EVAP canister purge volume control
solenoid valve.
Foreign matter caught in EVAP canister
vent control valve.
EVAP canister or fuel tank leaks
EVAP purge line (pipe and rubber tube)
leaks
EVAP purge line rubber tube bent.
Loose or disconnected rubber tube
EVAP canister vent control valve and the
circuit
EVAP canister purge volume control solenoid valve and the circuit
Fuel tank temperature sensor
O-ring of EVAP canister vent control
valve is missing or damaged.
EVAP control system pressure sensor
Refueling EVAP vapor cut valve
ORVR system leaks

CAUTION:
Use only a genuine NISSAN fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the
MIL may come on.
If the fuel filler cap is not tightened properly, the MIL may come on.
Use only a genuine NISSAN rubber tube as a replacement.

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
CAUTION:
Revision: 2007 June

EC-318

G37 Coupe

P0455 EVAP CONTROL SYSTEM

[VQ37VHR]
< COMPONENT DIAGNOSIS >
Never remove fuel filler cap during the DTC Confirmation Procedure.
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct- A
ing the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
EC
3. Turn ignition switch OFF and wait at least 10 seconds.
NOTE:
Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve
properly.
C
TESTING CONDITION:
Perform DTC WORK SUPPORT when the fuel level is between 1/4 and 3/4 full, and vehicle is placed
on flat level surface.
D
Open engine hood before conducting the following procedures.
Do you have CONSULT-III?
YES >> GO TO 2.
E
NO
>> GO TO 4.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
1. Tighten fuel filler cap securely until ratcheting sound is heard.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
5. Make sure that the following conditions are met.
COOLAN TEMP/S: 0 - 70C (32 - 158F)
INT/A TEMP SE: 0 - 60C (32 - 140F)
6. Select EVAP SML LEAK P0442/P1442 of EVAPORATIVE SYSTEM in DTC WORK SUPPORT mode
with CONSULT-III.
Follow the instruction displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on the CONSULT-III screen, go to
EC-13, "BASIC INSPECTION : Special Repair Requirement".
Which is displayed on CONSULT-III screen?
OK
>> Go to EC-320, "Diagnosis Procedure".
NG
>> GO TO 3.

3.CHECK DTC
Check DTC.
Which DTC is detected?
P0455 >> Go to EC-326, "Diagnosis Procedure".
P0442 >> Go to EC-283, "Diagnosis Procedure".

With GST
NOTE:
Be sure to read the explanation of Driving Pattern in EC-557, "How to Set SRT Code" before driving vehicle.
1. Start engine.
2. Drive vehicle according to Driving Pattern.
3. Stop vehicle.
4. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
5. Check 1st trip DTC.
Is 1st trip DTC detected?
YES-1 >> P0455: Go to EC-326, "Diagnosis Procedure".
YES-2 >> P0442: Go to EC-283, "Diagnosis Procedure".
YES-3 >> P0441: Go to EC-279, "Diagnosis Procedure".
NO
>> INSPECTION END

EC-319

4.PERFORM DTC CONFIRMATION PROCEDURE

Revision: 2007 June

G37 Coupe

P0455 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001734137

1.CHECK FUEL FILLER CAP DESIGN

1. Turn ignition switch OFF.
2. Check for genuine NISSAN fuel filler cap design.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Replace with genuine NISSAN fuel filler cap.

SEF915U

2.CHECK FUEL FILLER CAP INSTALLATION

Check that the cap is tightened properly by rotating the cap clockwise.
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Open fuel filler cap, then clean cap and fuel filler neck threads using air blower. Retighten until
ratcheting sound is heard.

3.CHECK FUEL FILLER CAP FUNCTION

Check for air releasing sound while opening the fuel filler cap.
Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.CHECK FUEL TANK VACUUM RELIEF VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace fuel filler cap with a genuine one.

5.CHECK EVAP PURGE LINE

Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks, improper connection or
disconnection.
Refer to EC-80, "System Diagram".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair or reconnect the hose.

6.CLEAN EVAP PURGE LINE

Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 7.

7.CHECK EVAP CANISTER VENT CONTROL VALVE

Check the following.
EVAP canister vent control valve is installed properly.
Refer to EC-604, "Removal and Installation".
EVAP canister vent control valve.
Refer to EC-298, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Repair or replace EVAP canister vent control valve and O-ring.
Revision: 2007 June

EC-320

G37 Coupe

P0455 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

8.CHECK FOR EVAP LEAK

Refer to EC-602, "Inspection".

Is there any leak in EVAP line?
YES >> Repair or replace.
NO-1 >> With CONSULT-III: GO TO 9.
NO-2 >> Without CONSULT-III: GO TO 10.

EC

9.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

With CONSULT-III
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
2. Start engine and let it idle.
3. Select PURG VOL CONT/V in ACTIVE TEST mode.
4. Touch Qu on CONSULT-III screen to increase PURG VOL CONT/V opening to 100%.
5. Check vacuum hose for vacuum.
1.

Vacuum should exist.

Is the inspection result normal?

YES >> GO TO 12.
NO
>> GO TO 11.

10.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

Without CONSULT-III
Start engine and warm it up to normal operating temperature.
Stop engine.
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
1.
2.
3.

Vacuum should exist.

Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 11.

11.CHECK VACUUM HOSE

L

Check vacuum hoses for clogging or disconnection. Refer to EC-80, "System Diagram".
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 12.
YES-2 >> Without CONSULT-III: GO TO 13.
NO
>> Repair or reconnect the hose.

12.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

With CONSULT-III
1. Start engine.
2. Perform PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-III. Check that engine speed varies according to the valve opening.
Does engine speed vary according to the valve opening?
YES >> GO TO 14.
NO
>> GO TO 13.

13.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

Refer to EC-291, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 14.
NO
>> Replace EVAP canister purge volume control solenoid valve.
Revision: 2007 June

EC-321

G37 Coupe

P0455 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

14.CHECK FUEL TANK TEMPERATURE SENSOR

Refer to EC-242, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace fuel level sensor unit.

15.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 16.
NO
>> Replace EVAP control system pressure sensor.

16.CHECK EVAP/ORVR LINE

Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper connection. For location, refer to EC-504, "Description".
Is the inspection result normal?
YES >> GO TO 17.
NO
>> Repair or replace hoses and tubes.

17.CHECK RECIRCULATION LINE

Check recirculation line between filler neck tube and fuel tank for clogging, kink, cracks, looseness and
improper connection.
Is the inspection result normal?
YES >> GO TO 18.
NO
>> Repair or replace hose, tube or filler neck tube.

18.CHECK REFUELING EVAP VAPOR CUT VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 19.
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

19.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910877

1.CHECK FUEL TANL VACUUM RELIEF VALVE

1.
2.
3.

Turn ignition switch OFF.

Remove fuel filler cap.
Wipe clean valve housing.

SEF445Y

Revision: 2007 June

EC-322

G37 Coupe

P0455 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

4. Check valve opening pressure and vacuum.

Pressure:

15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 2.90 psi)

Vacuum:

6.0 to 3.3 kPa (0.061 to 0.034 kg/cm2,

0.87 to 0.48 psi)

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

C
SEF943S

2.REPLACE FUEL FILLER CAP

Replace fuel filler cap.

CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may
come on.

>> INSPECTION END

Revision: 2007 June

EC-323

G37 Coupe

P0456 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0456 EVAP CONTROL SYSTEM

DTC Logic

INFOID:0000000001734139

DTC DETECTION LOGIC

NOTE:
If DTC P0456 is displayed with DTC P0442, first perform the trouble diagnosis for DTC P0456.
This diagnosis detects very small leaks in the EVAP line between fuel tank and EVAP canister purge volume
control solenoid valve, using the intake manifold vacuum in the same way as conventional EVAP small leak
diagnosis.
If ECM judges a leak which corresponds to a very small leak, the very small leak P0456 will be detected.
If ECM judges a leak equivalent to a small leak, EVAP small leak P0442 will be detected.
If ECM judges there are no leaks, the diagnosis will be OK.

PBIB1026E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0456

Evaporative emission
control system very
small leak (negative
pressure check)

EVAP system has a very small leak.

EVAP system does not operate properly.

Incorrect fuel tank vacuum relief valve

Incorrect fuel filler cap used
Fuel filler cap remains open or fails to close.
Foreign matter caught in fuel filler cap.
Leak is in line between intake manifold and EVAP
canister purge volume control solenoid valve.
Foreign matter caught in EVAP canister vent control valve.
EVAP canister or fuel tank leaks
EVAP purge line (pipe and rubber tube) leaks
EVAP purge line rubber tube bent
Loose or disconnected rubber tube
EVAP canister vent control valve and the circuit
EVAP canister purge volume control solenoid
valve and the circuit
Fuel tank temperature sensor
O-ring of EVAP canister vent control valve is missing or damaged
EVAP canister is saturated with water
EVAP control system pressure sensor
Refueling EVAP vapor cut valve
ORVR system leaks
Fuel level sensor and the circuit
Foreign matter caught in EVAP canister purge volume control solenoid valve

CAUTION:
Use only a genuine NISSAN fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the
MIL may come on.
Revision: 2007 June

EC-324

G37 Coupe

P0456 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
If the fuel filler cap is not tightened properly, the MIL may come on.
Use only a genuine NISSAN rubber tube as a replacement.

[VQ37VHR]
A

DTC CONFIRMATION PROCEDURE

1.INSPECTION START

EC

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 4.

2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
NOTE:
After repair, make sure that the hoses and clips are installed properly.
TESTING CONDITION:
Open engine hood before conducting following procedure.
If any of following conditions are met just before the DTC confirmation procedure, leave the vehicle
for more than 1 hour.
- Fuel filler cap is removed.
- Fuel is refilled or drained.
- EVAP component parts is/are removed.
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve
properly.

>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON and select DATA MONITOR mode with CONSULT-III.
Make sure the following conditions are met.
FUEL LEVEL SE: 0.25 - 1.4V
COOLAN TEMP/S: 0 - 32C (32 - 90F)
FUEL T/TMP SE: 0 - 35C (32 - 95F)
INT A/TEMP SE: More than 0C (32F)
If NG, turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle) or refilling/draining
fuel until the output voltage condition of the FUEL LEVEL SE meets within the range above and leave
the vehicle for more than 1 hour. Then start from step 1).
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Select EVAP V/S LEAK P0456/P1456 of EVAPORATIVE SYSTEM in DTC WORK SUPPORT mode
with CONSULT-III.
Follow the instruction displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on CONSULT-III screen, go to
EC-13, "BASIC INSPECTION : Special Repair Requirement".
Which is displayed on CONSULT-III screen?
OK
>> INSPECTION END
NG
>> Go to EC-326, "Diagnosis Procedure".
1.
2.

4.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-326, "Component Function Check".
NOTE:
Use component function check to check the overall function of the EVAP very small leak function. During this
check, a 1st trip DTC might not be confirmed.
Revision: 2007 June

EC-325

G37 Coupe

P0456 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-326, "Diagnosis Procedure".

Component Function Check

[VQ37VHR]

INFOID:0000000001734140

1.PERFORM COMPONENT FUNCTION CHECK

With GST
CAUTION:
Do not use compressed air, doing so may damage the EVAP system.
Do not start engine.
Do not exceeded 4.12 kPa (0.042 kg/cm2, 0.6 psi).
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Set the pressure pump and a hose.
3. Also set a vacuum gauge via 3-way connector and a hose.
4. Turn ignition switch ON.
5. Connect GST and select Service $08.
6. Using Service $08 control the EVAP canister vent control valve
(close).
7. Apply pressure and make sure the following conditions are satisfied.
Pressure to be applied: 2.7 kPa (0.028 kg/cm2, 0.39 psi)
Time to be waited after the pressure drawn in to the EVAP
system and the pressure to be dropped: 60 seconds and
the pressure should not be dropped more than 0.4 kPa
(0.004 kg/cm2, 0.06 psi).
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Go to EC-326, "Diagnosis Procedure".

SEF462UI

2.RELEASE PRESSURE
1.
2.
3.
4.
5.
6.
7.
8.

Disconnect GST.
Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds.
Restart engine and let it idle for 90 seconds.
Keep engine speed at 2,000 rpm for 30 seconds.
Turn ignition switch OFF.
NOTE:
For more information, refer to GST Instruction Manual.
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734141

1.CHECK FUEL FILLER CAP DESIGN

1.

Turn ignition switch OFF.

Revision: 2007 June

EC-326

G37 Coupe

P0456 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
2. Check for genuine NISSAN fuel filler cap design.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Replace with genuine NISSAN fuel filler cap.

[VQ37VHR]
A

EC

C
SEF915U

2.CHECK FUEL FILLER CAP INSTALLATION

Check that the cap is tightened properly by rotating the cap clockwise.
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Open fuel filler cap, then clean cap and fuel filler neck threads using air blower. Retighten until
ratcheting sound is heard.

3.CHECK FUEL FILLER CAP FUNCTION

Check for air releasing sound while opening the fuel filler cap.
Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.CHECK FUEL TANK VACUUM RELIEF VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace fuel filler cap with a genuine one.

5.CHECK FOR EVAP LEAK

Refer to EC-602, "Inspection".

Is there any leak in EVAP line?
YES >> Repair or replace.
NO
>> GO TO 6.

6.CHECK EVAP CANISTER VENT CONTROL VALVE

Check the following.

EVAP canister vent control valve is installed properly.
Refer to EC-604, "Removal and Installation".
EVAP canister vent control valve.
Refer to EC-298, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair or replace EVAP canister vent control valve and O-ring.

7.CHECK IF EVAP CANISTER SATURATED WITH WATER

1.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
P

Revision: 2007 June

EC-327

G37 Coupe

P0456 EVAP CONTROL SYSTEM

< COMPONENT DIAGNOSIS >
2. Check if water will drain from EVAP canister (1).
2

[VQ37VHR]

: EVAP canister vent control valve

Does water drain from the EVAP canister?

YES >> GO TO 8.
NO-1 >> With CONSULT-III: GO TO 10.
NO-2 >> Without CONSULT-III: GO TO 11.

PBIB2731E

8.CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 10.
YES-2 >> Without CONSULT-III: GO TO 11.
NO
>> GO TO 9.

9.DETECT MALFUNCTIONING PART

Check the following.
EVAP canister for damage
EVAP hose between EVAP canister and vehicle frame for clogging or poor connection
>> Repair hose or replace EVAP canister.

10.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

With CONSULT-III
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
2. Start engine and let it idle.
3. Select PURG VOL CONT/V in ACTIVE TEST mode.
4. Touch Qu on CONSULT-III screen to increase PURG VOL CONT/V opening to 100%.
5. Check vacuum hose for vacuum.

1.

Vacuum should exist.

Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.

11.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

Without CONSULT-III
Start engine and warm it up to normal operating temperature.
Stop engine.
Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.

1.
2.
3.

Vacuum should exist.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 12.

12.CHECK VACUUM HOSE

Check vacuum hoses for clogging or disconnection. Refer to EC-80, "System Diagram".
Revision: 2007 June

EC-328

G37 Coupe

P0456 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 13.
NO
>> Repair or reconnect the hose.

13.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

EC

Refer to EC-291, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 14.
NO
>> Replace EVAP canister purge volume control solenoid valve.

14.CHECK FUEL TANK TEMPERATURE SENSOR

D

Refer to EC-242, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace fuel level sensor unit.

15.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to EC-306, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 16.
NO
>> Replace EVAP control system pressure sensor.

16.CHECK EVAP PURGE LINE

Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
Refer to EC-80, "System Diagram".
Is the inspection result normal?
YES >> GO TO 17.
NO
>> Repair or reconnect the hose.

17.CLEAN EVAP PURGE LINE

J

Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 18.

18.CHECK EVAP/ORVR LINE

Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper connection. For location, refer to EC-504, "Description".
Is the inspection result normal?
YES >> GO TO 19.
NO
>> Repair or replace hoses and tubes.

19.CHECK RECIRCULATION LINE

Check recirculation line between filler neck tube and fuel tank for clogging, kink, cracks, looseness and
improper connection.
Is the inspection result normal?
YES >> GO TO 20.
NO
>> Repair or replace hose, tube or filler neck tube.

20.CHECK REFUELING EVAP VAPOR CUT VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

21.CHECK FUEL LEVEL SENSOR

Refer to MWI-55, "Component Inspection".
Is the inspection result normal?
Revision: 2007 June

EC-329

G37 Coupe

P0456 EVAP CONTROL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 22.
NO
>> Replace fuel level sensor unit.

22.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001910878

1.CHECK FUEL TANL VACUUM RELIEF VALVE

1.
2.
3.

Turn ignition switch OFF.

Remove fuel filler cap.
Wipe clean valve housing.

SEF445Y

4.

Check valve opening pressure and vacuum.

Pressure:

15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 2.90 psi)

Vacuum:

6.0 to 3.3 kPa (0.061 to 0.034 kg/cm2,

0.87 to 0.48 psi)

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.
SEF943S

2.REPLACE FUEL FILLER CAP

Replace fuel filler cap.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may
come on.
>> INSPECTION END

Revision: 2007 June

EC-330

G37 Coupe

P0460 FUEL LEVEL SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0460 FUEL LEVEL SENSOR

Description

INFOID:0000000001734143

The fuel level sensor is mounted in the fuel level sensor unit.
EC
The sensor detects a fuel level in the fuel tank and transmits a signal to the unified meter and A/C amp.. The
unified meter and A/C amp. sends the fuel level sensor signal to the ECM through CAN communication line.
It consists of two parts, one is mechanical float and the other is variable resistor. Fuel level sensor output voltC
age changes depending on the movement of the fuel mechanical float.

DTC Logic

INFOID:0000000001734144

DTC DETECTION LOGIC

NOTE:
If DTC P0460 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001.Refer to EC-146, "DTC Logic".
If DTC P0460 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
When the vehicle is parked, naturally the fuel level in the fuel tank is stable. It means that output signal of the
fuel level sensor does not change. If ECM senses sloshing signal from the sensor, fuel level sensor malfunction is detected.

G
DTC No.

P0460

Trouble diagnosis name

Fuel level sensor circuit

noise

DTC detecting condition

Possible cause

Even though the vehicle is parked, a signal being varied is sent from the fuel level sensor to
ECM.

Harness or connectors
(The CAN communication line is open or
shorted)
Harness or connectors
(The sensor circuit is open or shorted)
Unified meter and A/C amp.
Fuel level sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and wait maximum of 2 consecutive minutes.

2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-331, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734145

1.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".

Is the inspection result normal?
YES >> GO TO 2.
NO
>> Go to MWI-54, "Component Function Check".

2.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Revision: 2007 June

EC-331

G37 Coupe

P0460 FUEL LEVEL SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> INSPECTION END

Revision: 2007 June

EC-332

G37 Coupe

P0461 FUEL LEVEL SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0461 FUEL LEVEL SENSOR

Description

INFOID:0000000001910891

The fuel level sensor is mounted in the fuel level sensor unit.
EC
The sensor detects a fuel level in the fuel tank and transmits a signal to the unified meter and A/C amp.. The
unified meter and A/C amp. sends the fuel level sensor signal to the ECM through CAN communication line.
It consists of two parts, one is mechanical float and the other is variable resistor. Fuel level sensor output voltC
age changes depending on the movement of the fuel mechanical float.

DTC Logic

INFOID:0000000001734147

DTC DETECTION LOGIC

NOTE:
If DTC P0461 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001.Refer to EC-146, "DTC Logic".
If DTC P0461 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
Driving long distances naturally affect fuel gauge level.
This diagnosis detects the fuel gauge malfunction of the gauge not moving even after a long distance has
been driven.

G
DTC No.

P0461

Trouble diagnosis name

Fuel level sensor circuit

range/performance

DTC detecting condition

Possible cause

The output signal of the fuel level sensor does

not change within the specified range even
though the vehicle has been driven a long distance.

Harness or connectors
(The CAN communication line is open or
shorted)
Harness or connectors
(The sensor circuit is open or shorted)
Unified meter and A/C amp.
Fuel level sensor

DTC CONFIRMATION PROCEDURE

1.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-333, "Component Function Check".
Use component function check to check the overall function of the fuel level sensor function. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-334, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734148

1.PRECONDITIONING
WARNING:
When performing following procedure, be sure to observe the handling of the fuel. Refer to FL-5,
"Removal and Installation".
TESTING CONDITION:
Before starting component function check, preparation of draining fuel and refilling fuel is required.
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.PERFORM COMPONENT FUNCTION CHECK

With CONSULT-III
NOTE:
Start from step 10, if it is possible to confirm that the fuel cannot be drained by 30
8 Imp gal) in advance.
Revision: 2007 June

EC-333

(7-7/8 US gal, 6-5/

G37 Coupe

P0461 FUEL LEVEL SENSOR

< COMPONENT DIAGNOSIS >
1. Prepare a fuel container and a spare hose.
2. Release fuel pressure from fuel line, refer to EC-601, "Inspection".
3. Remove the fuel feed hose on the fuel level sensor unit.
4. Connect a spare fuel hose where the fuel feed hose was removed.
5. Turn ignition switch OFF and wait at least 10 seconds then turn ON.
6. Select FUEL LEVEL SE in DATA MONITOR mode with CONSULT-III.
7. Check FUEL LEVEL SE output voltage and note it.
8. Select FUEL PUMP RELAY in ACTIVE TEST mode with CONSULT-III.
9. Touch ON and drain fuel approximately 30 (7-7/8 US gal, 6-5/8 Imp gal) and stop it.
10. Check FUEL LEVEL SE output voltage and note it.
11. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
12. Check FUEL LEVEL SE output voltage and note it.
13. Confirm whether the voltage changes more than 0.03V during step 7 to 10 and 10 to 12.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-334, "Diagnosis Procedure".

[VQ37VHR]

3.PERFORM COMPONENT FUNCTION CHECK

Without CONSULT-III
NOTE:
Start from step 8, if it is possible to confirm that the fuel cannot be drained by 30 (7-7/8 US gal, 6-5/8
Imp gal) in advance.
1. Prepare a fuel container and a spare hose.
2. Release fuel pressure from fuel line. Refer to EC-601, "Inspection".
3. Remove the fuel feed hose on the fuel level sensor unit.
4. Connect a spare fuel hose where the fuel feed hose was removed.
5. Turn ignition switch ON.
6. Drain fuel by 30 (7-7/8 US gal, 6-5/8 Imp gal) from the fuel tank using proper equipment.
7. Confirm that the fuel gauge indication varies.
8. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
9. Confirm that the fuel gauge indication varies.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-334, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001910892

1.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Go to MWI-54, "Component Function Check".

2.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Revision: 2007 June

EC-334

G37 Coupe

P0462, P0463 FUEL LEVEL SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0462, P0463 FUEL LEVEL SENSOR

Description

A
INFOID:0000000001910893

The fuel level sensor is mounted in the fuel level sensor unit.
EC
The sensor detects a fuel level in the fuel tank and transmits a signal to the unified meter and A/C amp.. The
unified meter and A/C amp. sends the fuel level sensor signal to the ECM through CAN communication line.
It consists of two parts, one is mechanical float and the other is variable resistor. Fuel level sensor output voltC
age changes depending on the movement of the fuel mechanical float.

DTC Logic

INFOID:0000000001734151

DTC DETECTION LOGIC

NOTE:
If DTC P0462 or P0463 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for
DTC U1000, U1001.Refer to EC-146, "DTC Logic".
If DTC P0462 or P0463 is displayed with DTC U1010, first perform the trouble diagnosis for DTC
U1010.Refer to EC-147, "DTC Logic".
This diagnosis indicates the former, to detect open or short circuit malfunction.
DTC No.

Trouble diagnosis name

DTC detecting condition

P0462

Fuel level sensor circuit

low input

An excessively low voltage from the sensor is

sent to ECM.

P0463

Fuel level sensor circuit

high input

An excessively high voltage from the sensor is

sent to ECM.

Possible cause
Harness or connectors
(The CAN communication line is open or
shorted)
Harness or connectors
(The sensor circuit is open or shorted)
Unified meter and A/C amp.
Fuel level sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at ignition
switch ON.
>> GO TO 2.
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-335, "Diagnosis Procedure".
NO
>> INSPECTION END

O
INFOID:0000000001910894

1.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".

Is the inspection result normal?
YES >> GO TO 2.
NO
>> Go to MWI-54, "Component Function Check".

2.CHECK INTERMITTENT INCIDENT

Revision: 2007 June

2.PERFORM DTC CONFIRMATION PROCEDURE

Diagnosis Procedure

EC-335

G37 Coupe

P0462, P0463 FUEL LEVEL SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Revision: 2007 June

EC-336

G37 Coupe

P0500 VSS
[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0500 VSS

Description

INFOID:0000000001734153

The vehicle speed signal is sent to the unified meter and A/C amp. from the ABS actuator and electric unit EC
(control unit) by CAN communication line. The unified meter and A/C amp. then sends a signal to the ECM
by CAN communication line.

DTC Logic

INFOID:0000000001734154

NOTE:
If DTC P0500 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146, "DTC Logic".
If DTC P0500 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".

DTC DETECTION LOGIC

DTC No.

P0500

Trouble diagnosis name

Vehicle speed sensor

DTC detecting condition

Possible cause

The almost 0 km/h (0 MPH) signal from

vehicle speed sensor is sent to ECM even
when vehicle is being driven.

Harness or connectors
(The CAN communication line is open or shorted)
Harness or connectors
(The vehicle speed signal circuit is open or
shorted)
Wheel sensor
Unified meter and A/C amp.
ABS actuator and electric unit (control unit)

DTC CONFIRMATION PROCEDURE

1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 5.

2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 3.

3.CHECK VEHICLE SPEED SENSOR FUNCTION

NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a
road test is expected to be easier, it is unnecessary to lift the vehicle.
With CONSULT-III
1. Start engine (VDC switch OFF).
2. Read VHCL SPEED SE in DATA MONITOR mode with CONSULT-III. The vehicle speed on CONSULT-III should exceed 10 km/h (6 MPH) when rotating wheels with suitable gear position.
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Go to EC-338, "Diagnosis Procedure".

4.PERFORM DTC CONFIRMATION PROCEDURE

1.

Select DATA MONITOR mode with CONSULT-III.

Revision: 2007 June

EC-337

G37 Coupe

P0500 VSS
< COMPONENT DIAGNOSIS >
2. Warm engine up to normal operating temperature.
3. Maintain the following conditions for at least 50 consecutive seconds.
CAUTION:
Always drive vehicle at a safe speed.
ENG SPEED

1,800 - 6,000 rpm

COOLAN TEMP/S

More than 70C (158F)

B/FUEL SCHDL

5.0 - 31.8 msec

Selector lever

Except P or N position (A/T)

Except Neutral position (M/T)

PW/ST SIGNAL

OFF

[VQ37VHR]

4. Check 1st trip DTC.

Is 1st trip DTC detected?
YES >> Go to EC-338, "Diagnosis Procedure".
NO
>> INSPECTION END

5.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-338, "Component Function Check".
Use component function check to check the overall function of the vehicle speed sensor circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-338, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734155

1.PERFORM COMPONENT FUNCTION CHECK

With GST
Lift up drive wheels.
Start engine.
Read vehicle speed sensor signal in Service $01 with GST.
The vehicle speed sensor on GST should be able to exceed 10 km/h (6 MPH) when rotating wheels with
suitable gear position.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-338, "Diagnosis Procedure".
1.
2.
3.

Diagnosis Procedure

INFOID:0000000001734156

1.CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Refer to BRC-26, "CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace.

2.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".
>> INSPECTION END

Revision: 2007 June

EC-338

G37 Coupe

P0506 ISC SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0506 ISC SYSTEM

Description

INFOID:0000000001734157

The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let EC
into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects
the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value C
memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan D
operation, etc.).

DTC Logic

INFOID:0000000001734158

DTC DETECTION LOGIC

NOTE:
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
DTC No.
P0506

Trouble diagnosis name

DTC detecting condition

Idle speed control system RPM lower than expected

The idle speed is less than the target idle speed

by 100 rpm or more.

Possible cause

G
Electric throttle control actuator
Intake air leak

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
If the target idle speed is out of the specified value, perform EC-19, "IDLE AIR VOLUME LEARNING :
Special Repair Requirement", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Always perform the test at a temperature above 10C(14F).

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and warm it up to normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and run it for at least 1 minute at idle speed.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-339, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734159

1.CHECK INTAKE AIR LEAK

1. Start engine and let it idle.
2. Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
Revision: 2007 June

EC-339

G37 Coupe

P0506 ISC SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> Discover air leak location and repair.
NO
>> GO TO 2.

2.REPLACE ECM
1.
2.
3.

Stop engine.
Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Revision: 2007 June

EC-340

G37 Coupe

P0507 ISC SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0507 ISC SYSTEM

Description

INFOID:0000000001910897

The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let EC
into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects
the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value C
memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan D
operation, etc.).

DTC Logic

INFOID:0000000001734161

DTC DETECTION LOGIC

NOTE:
If DTC P0507 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
DTC No.
P0507

Trouble diagnosis name

Idle speed control system RPM higher than
expected

DTC detecting condition

The idle speed is more than the target idle
speed by 200 rpm or more.

Possible cause
Electric throttle control actuator
Intake air leak
PCV system

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
If the target idle speed is out of the specified value, perform EC-19, "IDLE AIR VOLUME LEARNING :
Special Repair Requirement", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Always perform the test at a temperature above 10C(14F).

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and warm it up to normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and run it for at least 1 minute at idle speed.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-341, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734162

1.CHECK PCV HOSE CONNECTION

Confirm that PCV hose is connected correctly.
Is the inspection result normal?
YES >> GO TO 2.
Revision: 2007 June

EC-341

G37 Coupe

P0507 ISC SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> Repair or replace.

2.CHECK INTAKE AIR LEAK

1. Start engine and let it idle.
2. Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES >> Discover air leak location and repair.
NO
>> GO TO 3.

3.REPLACE ECM
1.
2.
3.

Stop engine.
Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Revision: 2007 June

EC-342

G37 Coupe

P0524 ENGINE OIL PRESSURE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0524 ENGINE OIL PRESSURE

DTC Logic

INFOID:0000000001903474

DTC DETECTION LOGIC

EC

NOTE:
If DTC P0524 is displayed with DTC P0075 or P0081, first perform the trouble diagnosis for DTC P0075,
P0081. Refer to EC-162, "DTC Logic"
Trouble diagnosis
name

DTC No.

P0524

Engine oil pressure

too low

Detecting condition

Possible cause

Engine oil pressure is low because there is a

gap between angle of target and phase-control
angle.

Engine oil pressure or level too low

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Intake valve control solenoid valve
Accumulation of debris to the signal pick-up
portion of the camshaft
Timing chain installation
Foreign matter caught in the oil groove for intake valve timing control

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING-I
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10V and 16V at
idle.

>> GO TO 2.

2.PRECONDITIONING-II

Check oil level and oil pressure. Refer to LU-6, "Inspection".

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Go to LU-6, "Inspection".

3.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
1. Select DATA MONITOR mode with CONSULT-III.
2. Maintain the following conditions for at least 20 consecutive seconds.
ENG SPEED

More than 1,700 rpm

COOLAN TEMP/S

More than 70C (158F)

Selector lever

1st or 2nd position

Driving location uphill

Driving vehicle uphill

(Increased engine load will help maintain the driving
conditions required for this test.)

CAUTION:
Always drive at a safe speed.
3. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Revision: 2007 June

EC-343

G37 Coupe

P0524 ENGINE OIL PRESSURE

< COMPONENT DIAGNOSIS >
Is 1st trip DTC detected?
YES >> Go to EC-344, "Diagnosis Procedure"
NO
>> INSPECTION END

Diagnosis Procedure

[VQ37VHR]

INFOID:0000000001910863

1.CHECK OIL PRESSURE WARNING LAMP

1.
2.

Start engine.
Check oil pressure warning lamp and confirm it is not illuminated.
Is oil pressure warning lamp illuminated?
YES >> Go to LU-6, "Inspection".
NO
>> GO TO 2.

PBIA8559J

2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE

Refer to EC-153, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

3.CHECK CRANKSHAFT POSITION SENSOR (POS)

Refer to EC-267, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Replace crankshaft position sensor (POS).

4.CHECK CAMSHAFT POSITION SENSOR (PHASE)

Refer to EC-271, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace malfunctioning camshaft position sensor (PHASE).

5.CHECK CAMSHAFT (INTAKE)

Check the following.
Accumulation of debris to the signal plate of camshaft front end
Chipping signal plate of camshaft front end
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Remove debris and clean the signal plate of camshaft
front end or replace camshaft.

JMBIA0962ZZ

6.CHECK TIMING CHAIN INSTALLATION

Check service records for any recent repairs that may cause timing chain misaligned.
Are there any service records that may cause timing chain misaligned?
YES >> Check timing chain installation. Refer to EM-49, "Removal and Installation".
NO
>> GO TO 7.
Revision: 2007 June

EC-344

G37 Coupe

P0524 ENGINE OIL PRESSURE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

7.CHECK LUBRICATION CIRCUIT

Perform Inspection of Camshaft Sprocket (INT) Oil Groove. Refer to EM-93, "Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Clean lubrication line.

EC

8.CHECK INTERMITTENT INCIDENT

C

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001910742

1.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect intake valve timing control solenoid valve harness connector.
Check resistance between intake valve timing control solenoid valve terminals as follows.
Terminals

Resistance

1 and 2

7.0 - 7.7 [at 20C (68F)]

1 or 2 and ground

(Continuity should not exist)

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-II

1.
2.

Remove intake valve timing control solenoid valve.

Provide 12V DC between intake valve timing control solenoid
valve terminals 1 and 2, and then interrupt it. Make sure that the
plunger moves as shown in the figure.
CAUTION:
Do not apply 12V DC continuously for 5 seconds or more.
Doing so may result in damage to the coil in intake valve
timing control solenoid valve.
NOTE:
Always replace O-ring when intake valve timing control
solenoid valve is removed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace malfunctioning intake valve timing control solenoid valve.

JMBIA0079ZZ

Revision: 2007 June

EC-345

G37 Coupe

P0550 PSP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0550 PSP SENSOR

Description

INFOID:0000000001734163

Power steering pressure (PSP) sensor is installed to the power steering high-pressure tube and detects a
power steering load.
This sensor is a potentiometer which transforms the power steering load into output voltage, and emits the
voltage signal to the ECM. The ECM controls the electric throttle control actuator and adjusts the throttle valve
opening angle to increase the engine speed and adjusts the idle speed for the increased load.

DTC Logic

INFOID:0000000001734164

DTC DETECTION LOGIC

NOTE:
If DTC P0550 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to
EC-358, "DTC Logic".
DTC No.

Trouble diagnosis name

Power steering pressure
sensor circuit

P0550

DTC detecting condition

An excessively low or high voltage from the
sensor is sent to ECM.

Possible cause
Harness or connectors
(The sensor circuit is open or shorted)
Power steering pressure sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-346, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734165

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK PSP SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect power steering pressure (PSP) sensor harness connector.

Turn ignition switch ON.
Check the voltage between PSP sensor harness connector and ground.
PSP sensor

Connector

Terminal

F35

Revision: 2007 June

Ground

Voltage

Ground

Approx. 5V

EC-346

G37 Coupe

P0550 PSP SENSOR

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]
A

3.CHECK PSP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

EC

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between PSP sensor harness connector and ECM harness connector.
PSP sensor

ECM

Connector

Terminal

Connector

Terminal

F35

F102

96

Continuity

D
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground short to power in harness or connectors.

4.CHECK PSP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between PSP sensor harness connector and ECM harness connector.
G
PSP sensor

ECM

Connector

Terminal

Connector

Terminal

F35

F102

87

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK PSP SENSOR

Refer to EC-347, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace PSP sensor.

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734166

1.CHECK POWER STEERING PRESSURE SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Start engine and let it idle.
Check the voltage between ECM harness connector and ground under the following conditions.

ECM
Connector

Terminal

F102

87

Ground

Ground

Condition

Steering wheel

Voltage

Being turned

0.5 - 4.5V

Not being turned

0.4 - 0.8V

Is the inspection result normal?

YES >> INSPECTION END
Revision: 2007 June

EC-347

G37 Coupe

P0550 PSP SENSOR

< COMPONENT DIAGNOSIS >
NO
>> Replace power steering pressure sensor.

Revision: 2007 June

EC-348

[VQ37VHR]

G37 Coupe

P0555 BRAKE BOOSTER PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0555 BRAKE BOOSTER PRESSURE SENSOR

Description

INFOID:0000000001736749

Brake booster pressure sensor is connected to brake booster by a

hose. It detects brake booster pressure and sends the voltage signal
to the ECM. The sensor uses a silicon diaphragm which is sensitive
to the change in pressure. As the pressure increases, the voltage
rises.

EC

JMBIA0878ZZ

DTC Logic

INFOID:0000000001736751

DTC DETECTION LOGIC

DTC No.

P0555

Trouble diagnosis name

Brake booster pressure sensor

circuit

DTC detecting condition

Possible cause

An excessively low voltage from the

sensor is sent to ECM.
An excessively high voltage from the
sensor is sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)
[CKP sensor (POS) circuit is shorted.]
(APP sensor 2 circuit is shorted)
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
Brake booster pressure sensor
Crankshaft position sensor (POS)
Accelerator pedal position sensor
EVAP control system pressure sensor
Refrigerant pressure sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 10 seconds.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-349, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736752

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
Revision: 2007 June

EC-349

G37 Coupe

P0555 BRAKE BOOSTER PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK BRAKE BOOSTER PRESSURE SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect brake booster pressure sensor harness connector.

Turn ignition switch ON.
Check the voltage between brake booster pressure sensor harness connector and ground.
Brake booster pressure sensor
Connector

Terminal

E48

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 9.
NO
>> GO TO 3.

3.CHECK BRAKE BOOSTER PRESSURE SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between Brake booster pressure sensor harness connector and ECM harness connector.
Brake booster pressure sensor

ECM

Continuity

Connector

Terminal

Connector

Terminal

E48

F101

45

Existed

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open between ECM and brake booster pressure sensor
>> Repair open circuit.

5.CHECK BRAKE BOOSTER PRESSURE SENSOR POWER SUPPLY CIRCUIT-III

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector
F101

M107

Sensor

Terminal

Name

Connector

Terminal

E48

F2

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

45

Brake booster pressure sensor

46

CKP sensor (POS)

103

Is the inspection result normal?

YES >> GO TO 6.
NO
>> Repair short to ground or short to power in harness or connectors.

6.CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-267, "Component Inspection".)
EVAP control system pressure sensor (Refer to EC-306, "Component Inspection".)
Revision: 2007 June

EC-350

G37 Coupe

P0555 BRAKE BOOSTER PRESSURE SENSOR

< COMPONENT DIAGNOSIS >
Refrigerant pressure sensor (Refer to HAC-85, "Component Function Check".)
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Replace malfunctioning component.

[VQ37VHR]
A

7.CHECK APP SENSOR

EC

Refer to EC-460, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 8.

8.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly

Go to EC-460, "Special Repair Requirement".
E

>> INSPECTION END

9.CHECK BRAKE BOOSTER PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between brake booster pressure sensor harness connector and ECM harness connector.
Brake booster pressure sensor

ECM

Connector

Terminal

Connector

Terminal

E48

F101

36

Continuity
Existed

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 11.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between brake booster pressure sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

11.CHECK BRAKE BOOSTER PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between brake booster pressure sensor harness connector and ECM harness connector.

Brake booster pressure sensor

ECM

Connector

Terminal

Connector

Terminal

E48

F101

39

Continuity
Existed

2. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.

12.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between brake booster pressure sensor and ECM

Revision: 2007 June

EC-351

G37 Coupe

P0555 BRAKE BOOSTER PRESSURE SENSOR

< COMPONENT DIAGNOSIS >
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]

13.CHECK BRAKE BOOSTER PRESSURE SENSOR

Refer to EC-352, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 14.
NO
>> Replace brake booster pressure sensor.

14.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001736753

1.CHECK BRAKE BOOSTER PRESSURE SENSOR-I

1.
2.
3.
4.

Turn ignition switch OFF.

Start engine and warm it up to normal operating temperature.
Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
Check the voltage between ECM harness connector terminals as follows.
ECM
Connector
F101

5.

6.

Terminal

Terminal

39

36

NOTE:
To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engine
is stopped.
Because the sensor is absolute pressure sensor, output value may differ depends on atmospheric pressure and altitude.
Measure the atmospheric pressure.
NOTE:
As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the
pressure with the following chart.
Altitude

Compensated pressure

0m

0hPa

200m

-24hPa

400m

-47hPa

600m

-70hPa

800m

-92hPa

1000m

-114hPa

1500m

-168hPa

2000m

-218hPa

Check the manifold absolute pressure sensor value corresponding to the atmospheric pressure.

Revision: 2007 June

EC-352

G37 Coupe

P0555 BRAKE BOOSTER PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Atmospheric pressure

Voltage

800hPa

3.1 3.7V

850hPa

3.3 3.9V

900hPa

3.5 4.1V

950hPa

3.8 4.3V

1000hPa

4.0 4.6V

1050hPa

4.2 - 4.8V

EC

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Replace brake booster pressure sensor.

JMBIA0870GB

2.CHECK BRAKE BOOSTER PRESSURE SENSOR-II

1.
2.
3.

Turn ignition switch OFF.

Remove brake booster pressure sensor with its harness connected.
Connect the hose of vacuum pump (A) to brake booster pressure sensor (1).

JMBIA0872ZZ

4.
5.

Turn ignition switch ON.

Check the voltage between ECM harness connector terminals as follows.

ECM
+

6.

Connector

Terminal

Connector

Terminal

F101

39

F101

36

Check that the difference of the voltage when engine is stopped and that when negative pressure is
applied with vacuum pump is within the following limits.

M
Vacuum

Voltage difference

-40kPa(-300mmHg)

1.5 2.0V

-53.3kPa(-400mmHg)

2.0 2.6V

-66.7kPa(-500mmHg)

2.6 3.2V

-80kPa(-600mmHg)

3.2 3.8V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace brake booster pressure sensor.

Revision: 2007 June

EC-353

G37 Coupe

P0603 ECM POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0603 ECM POWER SUPPLY

Description

INFOID:0000000001734167

Battery voltage is supplied to the ECM even when the ignition switch
is turned OFF for the ECM memory function of the DTC memory, the
air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc.

JMBIA0057ZZ

DTC Logic

INFOID:0000000001734168

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

ECM power supply circuit

P0603

DTC detecting condition

ECM back-up RAM system does not function
properly.

Possible cause
Harness or connectors
[ECM power supply (back-up) circuit is
open or shorted.]
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 1 second.
2. Start engine and let it idle for 1 second.
3. Turn ignition switch OFF, wait at least 10 seconds, and then turn ON.
4. Repeat steps 2 and 3 for four times.
5. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-354, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734169

1.CHECK ECM POWER SUPPLY

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

F102

93

Revision: 2007 June

Ground

Voltage

Ground

Battery voltage

EC-354

G37 Coupe

P0603 ECM POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 3.
NO
>> GO TO 2.

2.DETECT MALFUNCTIONING PART

EC

Check the following.

Harness connectors E3, F1
15A fuse (No. 50)
IPDM E/R harness connector E7
Harness for open or short between ECM and battery

>> Repair or replace harness or connectors.

3.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair or replace harness or connectors.

4.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-354, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-354, "DTC Logic".
Is the 1st trip DTC P0603 displayed again?
YES >> GO TO 5.
NO
>> INSPECTION END

1.
2.
3.
4.

5.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".

>> INSPECTION END

Revision: 2007 June

EC-355

G37 Coupe

P0605 ECM
[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0605 ECM
Description

INFOID:0000000001734170

The ECM consists of a microcomputer and connectors for signal

input and output and for power supply. The ECM controls the engine.

JMBIA0057ZZ

DTC Logic

INFOID:0000000001734171

DTC DETECTION LOGIC

DTC No.

P0605

Trouble diagnosis name

Engine control module

DTC detecting condition

A)

ECM calculation function is malfunctioning.

B)

ECM EEP-ROM system is malfunctioning.

C)

ECM self shut-off function is malfunctioning.

Possible cause

ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

1. Turn ignition switch ON.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-357, "Diagnosis Procedure".
NO
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B

1. Turn ignition switch ON and wait at least 1 second.
2. Turn ignition switch OFF, wait at least 10 seconds, and then turn ON.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-357, "Diagnosis Procedure".
NO
>> GO TO 4.

4.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION C

1. Turn ignition switch ON and wait at least 1 second.
2. Turn ignition switch OFF, wait at least 10 seconds, and then turn ON.
3. Repeat step 2 for 32 times.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
Revision: 2007 June

EC-356

G37 Coupe

P0605 ECM
< COMPONENT DIAGNOSIS >
YES >> Go to EC-357, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

[VQ37VHR]
A
INFOID:0000000001734172

1.INSPECTION START

EC

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-356, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-356, "DTC Logic".
Is the 1st trip DTC P0605 displayed again?
YES >> GO TO 2.
NO
>> INSPECTION END
1.
2.
3.
4.

2.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".

>> INSPECTION END

I

Revision: 2007 June

EC-357

G37 Coupe

P0643 SENSOR POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0643 SENSOR POWER SUPPLY

DTC Logic

INFOID:0000000001734173

DTC DETECTION LOGIC

DTC No.

P0643

Trouble diagnosis
name

Sensor power supply

circuit short

DTC detecting condition

ECM detects a voltage of power

source for sensor is excessively low
or high.

Possible cause
Harness or connectors
(APP sensor 1 circuit is shorted.)
(TP sensor circuit is shorted.)
[CMP sensor (PHASE) (bank 1) circuit is shorted.]
[Manifold absolute pressure (MAP) sensor circuit is
shorted.]
(PSP sensor circuit is shorted.)
[CMP sensor (PHASE) (bank 2) circuit is shorted.]
[Battery current sensor circuit is shorted/]
Accelerator pedal position sensor
Throttle position sensor
Camshaft position sensor (PHASE) (bank 1)
Manifold absolute pressure (MAP) sensor
Power steering pressure sensor
Camshaft position sensor (PHASE) (bank 2)
Battery current sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-358, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734174

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect accelerator pedal position (APP) sensor harness connector.

Turn ignition switch ON.
Check the voltage between APP sensor harness connector and ground.

Revision: 2007 June

EC-358

G37 Coupe

P0643 SENSOR POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

APP sensor
Connector

Terminal

E112

Ground

Voltage

Ground

Approx. 5V

EC

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 3.

3.CHECK SENSOR POWER SUPPLY CIRCUITS

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector
F101

Sensor

Terminal

Name

Connector

Terminal

43

Electric throttle control actuator (bank 2)

F27

44

Electric throttle control actuator (bank 1)

F6

CMP sensor (PHASE) (bank 1)

F5

Manifold absolute pressure (MAP) sensor

F50

PSP sensor

F35

CMP sensor (PHASE) (bank 2)

F18

Battery current sensor

E21

APP sensor

E112

60
F102
64
M107

99

Is the inspection result normal?

YES >> GO TO 4.
NO
>> Repair short to ground or short to power in harness or connectors.

4.CHECK COMPONENTS

Check the following.

Camshaft position sensor (PHASE) (bank 1) (Refer to EC-271, "Component Inspection".)
Manifold absolute pressure (MAP) sensor (Refer to EC-178, "Component Inspection".)
Power steering pressure sensor (Refer to EC-347, "Component Inspection".)
Camshaft position sensor (PHASE) (bank 2) (Refer to EC-271, "Component Inspection".)
Battery current sensor (Refer to EC-410, "Component Inspection".)
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace malfunctioning component.

5.CHECK TP SENSOR

Refer to EC-189, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 6.

6.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace electric throttle control actuator.

Go to EC-189, "Special Repair Requirement".
P

>> INSPECTION END

7.CHECK APP SENSOR

Refer to EC-460, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
Revision: 2007 June

EC-359

G37 Coupe

P0643 SENSOR POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> GO TO 8.

8.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-460, "Special Repair Requirement".
>> INSPECTION END

9.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Revision: 2007 June

EC-360

G37 Coupe

P0850 PNP SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P0850 PNP SWITCH

Description

INFOID:0000000001734175

When the selector lever position is P or N (A/T), Neutral position (M/T), park/neutral position (PNP) switch is EC
ON.
ECM detects the position because the continuity of the line (the ON signal) exists.

DTC Logic

INFOID:0000000001734176

DTC DETECTION LOGIC

D
DTC No.

P0850

Trouble diagnosis name

Park/neutral position
switch

DTC detecting condition

The signal of the park/neutral position (PNP)
switch is not changed in the process of engine
starting and driving.

Possible cause
Harness or connectors
[The park/neutral position (PNP) switch
circuit is open or shorted.]
Park/neutral position (PNP) switch
TCM (A/T models)

DTC CONFIRMATION PROCEDURE

1.INSPECTION START

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 5.

2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 3.

3.CHECK PNP SWITCH FUNCTION

1.
2.

With CONSULT-III
Turn ignition switch ON.
Select P/N POSI SW in DATA MONITOR mode with CONSULT-III. Then check the P/N POSI SW signal under the following conditions.
Position (Selector lever)

Known-good signal

N or P position (A/T)
Neutral position (M/T)

ON

Except above position

OFF

Is the inspection result normal?

YES >> GO TO 4.
NO
>> Go to EC-362, "Diagnosis Procedure".

4.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.

Select DATA MONITOR mode with CONSULT-III.

Start engine and warm it up to normal operating temperature.
Maintain the following conditions for at least 50 consecutive seconds.
CAUTION:
Always drive vehicle at a safe speed.

Revision: 2007 June

EC-361

G37 Coupe

P0850 PNP SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ENG SPEED

1,400 - 6,375 rpm

COOLAN TEMP/S

More than 70C (158F)

B/FUEL SCHDL

2.0 - 31.8 msec

VHCL SPEED SE

More than 64 km/h (40 mph)

Selector lever

Suitable position

4. Check 1st trip DTC.

Is 1st trip DTC detected?
YES >> Go to EC-362, "Diagnosis Procedure".
NO
>> INSPECTION END

5.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-362, "Component Function Check".
NOTE:
Use component function check the overall function of the park/neutral position (PNP) switch circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-362, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734177

1.PERFORM COMPONENT FUNCTION CHECK

1.
2.

Turn ignition switch ON.

Check the voltage between ECM harness connector and ground.
ECM

Connector
M107

Terminal
109

Ground

Ground

Condition

Selector lever

Voltage

P or N (A/T)
Neutral (M/T)

Approx. 0V

Except above

Battery voltage

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-362, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734178

1.INSPECTION START
Check which type of transmission the vehicle is equipped with.
Which type of transmission?
A/T
>> GO TO 2.
M/T
>> GO TO 7.

2.CHECK DTC WITH TCM

Refer to TM-108, "Diagnosis Description".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.CHECK STARTING SYSTEM

Turn ignition switch OFF, then turn it to START.
Does starter motor operate?
YES >> GO TO 4.
Revision: 2007 June

EC-362

G37 Coupe

P0850 PNP SWITCH

[VQ37VHR]
< COMPONENT DIAGNOSIS >
NO
>> Check DTC with BCM. Refer to DLK-50, "COMMON ITEM : CONSULT-III Function (BCM - COMMON ITEM)".

4.CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect A/T assembly harness connector.
Disconnect ECM harness connector.
Check the continuity between A/T assembly harness connector and ECM harness connector.

EC

C
A/T assembly

ECM

Connector

Terminal

Connector

Terminal

F51

M107

109

Continuity

Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness connectors E106, M6
Harness for open or short between A/T assembly and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

7.CHECK PNP SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect park/neutral position (PNP) switch harness connector.
Turn ignition switch ON.
Check the voltage between PNP switch harness connector and ground.

PNP switch
Connector

Terminal

F55

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
10A fuse (No. 43)
IPDM E/R harness connector E7
Harness for open or short between PNP switch and fuse

>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between PNP switch harness connector and ECM harness connector.

Revision: 2007 June

EC-363

G37 Coupe

P0850 PNP SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

PNP switch

ECM

Connector

Terminal

Connector

Terminal

F55

M107

109

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 11.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F103, M116
Harness for open or short between PNP switch and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

11.CHECK PNP SWITCH

Refer to TM-9, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 12.
NO
>> Replace PNP switch.

12.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair or replace.

Revision: 2007 June

EC-364

G37 Coupe

P100A, P100B VVEL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P100A, P100B VVEL SYSTEM

DTC Logic

INFOID:0000000001830767

DTC DETECTION LOGIC

EC

NOTE:
If DTC P100A or P100B is displayed with DTC P1090 or P1093, first perform the trouble diagnosis for DTC
P1090 or P1093. Refer to EC-378, "DTC Logic".

DTC No.

Trouble diagnosis name

P100A

VVEL response malfunction (bank 1)

P100B

VVEL response malfunction (bank 2)

DTC detecting condition

Actual event response to target is

poor.

Possible cause
Harness or connectors
(VVEL actuator motor circuit is
open or shorted.)
VVEL actuator motor
VVEL actuator sub assembly
VVEL ladder assembly
VVEL control module

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine.
2. Depress the accelerator pedal rapidly half or more under no load and then release it.
3. Wait at idle for 5 seconds or more.
4. Repeat steps 2 to 3 for three times.
5. Check 1st trip DTC.
Is DTC detected?
YES >> Go to EC-365, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001830768

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.VVEL ACTUATOR MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Disconnect VVEL control module harness connector.

Disconnect VVEL actuator motor harness connector.
Check the continuity between VVEL control module harness connector and VVEL actuator motor harness
connector.

Revision: 2007 June

EC-365

G37 Coupe

P100A, P100B VVEL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC No.

VVEL control module

Bank

Connector

VVEL actuator motor

Terminal

Connector

Terminal

12
P100A

F48
25
E15
2

P100B

F49
15

Continuity

Existed

Not existed

Not existed

Existed

Existed

Not existed

Not existed

Existed

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between VVEL actuator motor and VVEL control module
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK VVEL ACTUATOR MOTOR

Refer to EC-367, "Component Inspection (VVEL ACTUATOR MOTOR)".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-368, "Special Repair Requirement".
>> INSPECTION END

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair or replace.

7.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> GO TO 8.

8.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.

Revision: 2007 June

EC-366

G37 Coupe

P100A, P100B VVEL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

See EC-365, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-365, "DTC Logic".
Is the DTC P100A or P100B displayed again?
YES >> GO TO 9.
NO
>> INSPECTION END

EC

9.CHECK VVEL ACTUATOR SUB ASSEMBLY

D

Refer to EC-368, "Component Inspection (VVEL ACTUATOR SUB ASSEMBLY)".

Is the inspection result normal?
YES >> GO TO 11.
NO
>> GO TO 10.

10.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-368, "Special Repair Requirement".

>> INSPECTION END

11.CHECK VVEL LADDER ASSEMBLY

Refer to EM-93, "Inspection".
Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.

12.REPLACE CYLINDER HEAD, VVEL LADDER ASSEMBLY AND VVEL ACTUATOR SUB ASSEMBLY
1.
2.

Replace cylinder head, VVEL ladder assembly and VVEL actuator sub assembly.
Go to EC-368, "Special Repair Requirement".

>> INSPECTION END

K

13.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection (VVEL ACTUATOR MOTOR)

INFOID:0000000001830770

1.CHECK VVEL ACTUATOR MOTOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect VVEL actuator motor harness connector.
Check resistance between VVEL actuator motor terminals as follows.
VVEL actuator motor
Terminal
1 and 2

O
Resistance
16 or less

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-368, "Special Repair Requirement".

Revision: 2007 June

EC-367

G37 Coupe

P100A, P100B VVEL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> INSPECTION END

Component Inspection (VVEL ACTUATOR SUB ASSEMBLY)

INFOID:0000000001830771

1.CHECK VVEL ACTUATOR SUB ASSEMBLY

1. Turn ignition switch OFF.
2. Remove VVEL actuator sub assembly. Refer to EM-84, "Disassembly and Assembly".
3. Turn the ball screw shaft to check that it works smoothly.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-368, "Special Repair Requirement".
>> INSPECTION END

Special Repair Requirement

INFOID:0000000001830773

1.PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

Refer to EC-21, "VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Special Repair Requirement".
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
>> END

Revision: 2007 June

EC-368

G37 Coupe

P1087, P1088 VVEL SYSTEM

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1087, P1088 VVEL SYSTEM

DTC Logic

INFOID:0000000001736759

DTC DETECTION LOGIC

EC

NOTE:
If DTC P1087 or P1088 is displayed with DTC P1090 or P1093.
Perform the trouble diagnosis for DTC P1090 or P1093. Refer to EC-374, "DTC Logic".
DTC No.

Trouble diagnosis name

P1087

VVEL small event angle malfunction

(bank 1)

P1088

VVEL small event angle malfunction

(bank 2)

DTC detecting condition

The event angle of VVEL control

shaft is always small.

C
Possible cause

Harness or connectors
(VVEL actuator motor circuit is
open or shorted.)
VVEL actuator motor
VVEL actuator sub assembly
VVEL ladder assembly
VVEL control module

Revision: 2007 June

EC-369

G37 Coupe

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

Description

INFOID:0000000001736764

VVEL control shaft position sensor (1) is placed on VVEL actuator

sub assembly and detects the control shaft position angle.
A magnet is pressed into the arm on the edge of control shaft.
The magnetic field changes as the magnet rotates together with the
arm resulting in the output voltage change of the sensor.
VVEL control module detects the actual position angle through the
voltage change and sends the signal to ECM.

JMBIA0835ZZ

DTC Logic

INFOID:0000000001736765

DTC DETECTION LOGIC

NOTE:
If DTC P1089 or P1092 is displayed with DTC P1608, first perform the trouble diagnosis for DTC P1608.
Refer to EC-451, "DTC Logic".
DTC No.

Trouble diagnosis name

P1089

VVEL control shaft position sensor

(bank 1) circuit

P1092

VVEL control shaft position sensor

(bank 2) circuit

DTC detecting condition

Possible cause

An excessively low voltage from the

sensor is sent to VVEL control module.
Harness or connectors
An excessively high voltage from the
(VVEL control shaft position sensor
sensor is sent to VVEL control module.
circuit is open or shorted.)
Rationally incorrect voltage is sent to
VVEL control shaft position sensor
VVEL control module compared with
the signals from VVEL control shaft po- VVEL control module
sition sensor 1 and VVEL control shaft
position sensor 2.

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-370, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736766

1.CHECK GROUND CONNECTION

1.
2.

Turn ignition switch OFF.

Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".

Revision: 2007 June

EC-370

G37 Coupe

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.VVEL CONTROL SHAFT POSITION SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

EC

Disconnect VVEL control shaft position sensor harness connector.

Turn ignition switch ON.
Check the voltage between VVEL control shaft position sensor harness connector and ground.

DTC No.

VVEL control shaft position sensor

Bank

P1089

Connector

P1092

Voltage

F46

Ground

Terminal

Ground

F47

Approx. 5V

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness for open or short between VVEL control shaft position sensor and VVEL control module

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK VVEL CONTROL SHAFT POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect VVEL control module harness connector.
Check the continuity between VVEL control shaft position sensor harness connector and VVEL control
module harness connector.

DTC No.

VVEL control shaft position sensor

Bank

Connector

F46

P1089

P1092

F47

VVEL control module

Terminal

Connector

Terminal

17

E15

2
5

K
Continuity

L
Existed

19

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness for open or short between VVEL control shaft position sensor and VVEL control module

>> Repair open circuit or short to ground or short to power in harness or connectors.

6.VVEL CONTROL SHAFT POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between VVEL control shaft position sensor harness connector and VVEL control
module harness connector.

Revision: 2007 June

EC-371

G37 Coupe

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC No.

VVEL control shaft position sensor

Bank

Connector

F46

P1089

P1092

F47

VVEL control module

Terminal

Connector

Terminal

Continuity

E15

1
4

16
5

Existed

18

2. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> GO TO 7.

7.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between VVEL control shaft position sensor and VVEL control module
>> Repair open circuit or short to ground or short to power in harness or connectors.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 9.
NO
>> Repair or replace.

9.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> GO TO 10.

10.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-370, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-370, "DTC Logic".
Is the DTC P1089 or P1092 displayed again?
YES >> GO TO 11.
NO
>> INSPECTION END
1.
2.
3.
4.

11.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-373, "Special Repair Requirement".
>> INSPECTION END

Revision: 2007 June

EC-372

G37 Coupe

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Special Repair Requirement

INFOID:0000000001910901

1.PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

Refer to EC-21, "VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Special Repair RequireEC
ment".
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".

>> END
E

Revision: 2007 June

EC-373

G37 Coupe

P1090, P1093 VVEL ACTUATOR MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1090, P1093 VVEL ACTUATOR MOTOR

Description

INFOID:0000000001766510

The VVEL actuator motor rotates the control shaft according to the control signal from the VVEL control module. The VVEL control module judges whether the VVEL actuator motor controls the angle properly by the
VVEL control shaft position sensor signal.

DTC Logic

INFOID:0000000001736768

DTC DETECTION LOGIC

NOTE:
If DTC P1090 or P1093 is displayed with DTC P1091, first perform the trouble diagnosis for DTC P1091.
Refer to EC-378, "DTC Logic".
DTC No.
P1090

P1093

Trouble diagnosis name

DTC detecting condition

Possible cause

Event angle difference between the

actual and the target is detected.
Abnormal current is sent to VVEL
actuator motor.

Harness or connectors
(VVEL actuator motor circuit is open
or shorted.)
VVEL actuator motor
VVEL actuator sub assembly
VVEL ladder assembly
VVEL control module

VVEL system performance (bank 1)

VVEL system performance (bank 2)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 10 second.
2. Keep the engine speed at about 3500rpm for at least 10 seconds under no load.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-374, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736769

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.VVEL ACTUATOR MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Disconnect VVEL control module harness connector.

Disconnect VVEL actuator motor harness connector.
Check the continuity between VVEL control module harness connector and VVEL actuator motor harness
connector.

Revision: 2007 June

EC-374

G37 Coupe

P1090, P1093 VVEL ACTUATOR MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC No.

VVEL control module

Bank

Connector

VVEL actuator motor

Terminal

Connector

Terminal

12
P1090

F48
25
E15
2

P1093

F49
15

A
Continuity

Existed

Not existed

Not existed

Existed

Existed

Not existed

Not existed

Existed

EC

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between VVEL actuator motor and VVEL control module

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK VVEL ACTUATOR MOTOR

I

Refer to EC-376, "Component Inspection (VVEL ACTUATOR MOTOR)".

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-377, "Special Repair Requirement".

>> INSPECTION END

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair or replace.

7.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> GO TO 8.

8.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.

Revision: 2007 June

EC-375

G37 Coupe

P1090, P1093 VVEL ACTUATOR MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

See EC-374, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-374, "DTC Logic".
Is the DTC P1090 or P1093 displayed again?
YES >> GO TO 9.
NO
>> INSPECTION END

9.CHECK VVEL ACTUATOR SUB ASSEMBLY

Refer to EC-377, "Component Inspection (VVEL ACTUATOR SUB ASSEMBLY)".
Is the inspection result normal?
YES >> GO TO 11.
NO
>> GO TO 10.

10.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-377, "Special Repair Requirement".
>> INSPECTION END

11.CHECK VVEL LADDER ASSEMBLY

Refer to EM-93, "Inspection".
Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.

12.REPLACE CYLINDER HEAD, VVEL LADDER ASSEMBLY AND VVEL ACTUATOR SUB ASSEMBLY
1.
2.

Replace cylinder head, VVEL ladder assembly and VVEL actuator sub assembly.
Go to EC-377, "Special Repair Requirement".
>> INSPECTION END

13.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection (VVEL ACTUATOR MOTOR)

INFOID:0000000001910899

1.CHECK VVEL ACTUATOR MOTOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect VVEL actuator motor harness connector.
Check resistance between VVEL actuator motor terminals as follows.
VVEL actuator motor
Terminal
1 and 2

Resistance
16 or less

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-377, "Special Repair Requirement".

Revision: 2007 June

EC-376

G37 Coupe

P1090, P1093 VVEL ACTUATOR MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> INSPECTION END

Component Inspection (VVEL ACTUATOR SUB ASSEMBLY)

INFOID:0000000001910900

EC

1.CHECK VVEL ACTUATOR SUB ASSEMBLY

1. Turn ignition switch OFF.
2. Remove VVEL actuator sub assembly. Refer to EM-84, "Disassembly and Assembly".
3. Turn the ball screw shaft to check that it works smoothly.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-377, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910902

1.PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

Refer to EC-21, "VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Special Repair Requirement".

>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".

J

>> END
K

Revision: 2007 June

EC-377

G37 Coupe

P1091 VVEL ACTUATOR MOTOR RELAY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1091 VVEL ACTUATOR MOTOR RELAY

Description

INFOID:0000000001736773

Power supply for the VVEL actuator motor is provided to the VVEL control module via VVEL actuator motor
relay. VVEL actuator motor relay is ON/OFF controlled by the VVEL control module. In addition, when the
VVEL actuator motor relay cannot be controlled by the VVEL control module for some reason, it ON/OFF controlled by ECM.

DTC Logic

INFOID:0000000001736774

DTC DETECTION LOGIC

DTC No.

P1091

Trouble diagnosis name

VVEL actuator motor relay circuit

DTC detecting condition

VVEL control module detects the
VVEL actuator motor relay is stuck
OFF.
VVEL control module detects the
VVEL actuator motor relay is stuck
ON.

Possible cause
Harness or connectors
(VVEL actuator motor relay circuit is
open or shorted.)
(Abort circuit is open or shorted.)
VVEL actuator motor relay
VVEL control module
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 1 seconds.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and wait at least 1 seconds.
4. Check DTC.
Is DTC detected?
YES >> Go to EC-378, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736775

1.VVEL ACTUATOR MOTOR RELAY POWER SUPPLY CIRCUIT-I

1.
2.

Turn ignition switch OFF.

Check the voltage between VVEL actuator motor relay harness connector and ground.
VVEL actuator motor relay
Connector
E16

Terminal
2
5

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 3.
NO
>> GO TO 2.
Revision: 2007 June

EC-378

G37 Coupe

P1091 VVEL ACTUATOR MOTOR RELAY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.DETECT MALFUNCTIONING PART

Check the following.

50A fusible link (letter N)
Harness for open or short between VVEL actuator motor relay and battery

EC

>> Repair open circuit or short to ground or short to power in harness or connectors.

3.VVEL ACTUATOR MOTOR RELAY POWER SUPPLY CIRCUIT-II

1.
2.
3.

Disconnect VVEL control module harness connector.

Disconnect VVEL actuator motor relay harness connector.
Check the continuity between VVEL actuator motor relay harness connector and VVEL control module
harness connector.
VVEL control module

VVEL actuator motor relay

Connector

Terminal

Connector

Terminal

E15

23

E16

Continuity
Existed

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.VVEL ACTUATOR MOTOR RELAY INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between VVEL actuator motor relay harness connector and VVEL control module
harness connector.
VVEL control module
Bank
1

Connector

Terminal

Connector

Terminal

E16

13

E15

VVEL actuator motor relay

I
Continuity

Existed

2. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK VVEL ACTUATOR MOTOR RELAY

Refer to EC-380, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace VVEL actuator motor relay.

6.CHECK ABORT CIRCUIT FOR OPEN AND SHORT

1.
2.

Disconnect ECM harness connector.

Check the continuity between VVEL control module harness connector and ECM harness connector.
O
VVEL control module

ECM

Connector

Terminal

Connector

Terminal

E15

21

F101

28

Continuity

P
Existed

3. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK INTERMITTENT INCIDENT

Revision: 2007 June

EC-379

G37 Coupe

P1091 VVEL ACTUATOR MOTOR RELAY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Repair or replace.

8.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> GO TO 9.

9.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-378, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-378, "DTC Logic".
Is the DTC P1091 displayed again?
YES >> GO TO 10.
NO
>> INSPECTION END
1.
2.
3.
4.

10.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

Component Inspection

INFOID:0000000001736776

1.CHECK VVEL ACTUATOR MOTOR RELAY

1.
2.
3.

Turn ignition switch OFF.

Remove VVEL actuator motor relay.
Check the continuity between VVEL actuator motor relay terminals under the following conditions.
Terminal
3 and 5

Condition
12V direct current supply between
terminals 1 and 2
No current supply

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace VVEL actuator motor relay.

Revision: 2007 June

JMBIA0876ZZ

EC-380

G37 Coupe

P1148, P1168 CLOSED LOOP CONTROL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1148, P1168 CLOSED LOOP CONTROL

DTC Logic

A
INFOID:0000000001734183

DTC DETECTION LOGIC

EC

NOTE:
DTC P1148 or P1168 is displayed with another DTC for A/F sensor 1.
Perform the trouble diagnosis for the corresponding DTC.
DTC No.

Trouble diagnosis name

DTC detecting condition

P1148

Closed loop control

function (bank 1)

The closed loop control function for bank 1 does

not operate even when vehicle is driving in the
specified condition.

P1168

Closed loop control

function (bank 2)

The closed loop control function for bank 2 does

not operate even when vehicle is driving in the
specified condition.

C
Possible cause
Harness or connectors
(The A/F sensor 1 circuit is open or shorted.)
A/F sensor 1
A/F sensor 1 heater

Revision: 2007 June

EC-381

G37 Coupe

P1211 TCS CONTROL UNIT

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1211 TCS CONTROL UNIT

Description

INFOID:0000000001734184

The malfunction information related to TCS is transferred through the CAN communication line from ABS
actuator and electric unit (control unit) to ECM.
Be sure to erase the malfunction information such as DTC not only for ABS actuator and electric unit
(control unit) but also for ECM after TCS related repair.

DTC Logic

INFOID:0000000001734185

DTC DETECTION LOGIC

Freeze frame data is not stored in the ECM for this self-diagnosis.
DTC No.
P1211

Trouble diagnosis name

TCS control unit

DTC detecting condition

ECM receives a malfunction information from
ABS actuator and electric unit (control unit).

Possible cause
ABS actuator and electric unit (control
unit)
TCS related parts

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for at least 60 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> EC-382, "Diagnosis Procedure"
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734186

Go to BRC-4, "Work Flow".

Revision: 2007 June

EC-382

G37 Coupe

P1212 TCS COMMUNICATION LINE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1212 TCS COMMUNICATION LINE

Description

INFOID:0000000001734187

This CAN communication line is used to control the smooth engine operation during the TCS operation. Pulse EC
signals are exchanged between ECM and ABS actuator and electric unit (control unit).
Be sure to erase the malfunction information such as DTC not only for ABS actuator and electric unit
(control unit) but also for ECM after TCS related repair.
C

DTC Logic

INFOID:0000000001734188

DTC DETECTION LOGIC

NOTE:
If DTC P1212 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146, "DTC Logic".
If DTC P1212 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
Freeze frame data is not stored in the ECM for this self-diagnosis.

F
DTC No.

P1212

Trouble diagnosis name

DTC detecting condition

Possible cause

TCS communication line

ECM can not receive the information from

ABS actuator and electric unit (control
unit) continuously.

Harness or connectors
(The CAN communication line is open or shorted.)
ABS actuator and electric unit (control unit)
Dead (Weak) battery

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
J

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for at least 10 seconds.

2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-383, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734189

Go to BRC-4, "Work Flow".

N

Revision: 2007 June

EC-383

G37 Coupe

P1217 ENGINE OVER TEMPERATURE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1217 ENGINE OVER TEMPERATURE

DTC Logic

INFOID:0000000001734190

DTC DETECTION LOGIC

NOTE:
If DTC P1217 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146, "DTC Logic".
If DTC P1217 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
DTC No.

P1217

Trouble diagnosis name

Engine over temperature (Overheat)

DTC detecting condition

Possible cause

Cooling fan does not operate properly (Overheat).

Cooling fan system does not operate properly (Overheat).
Engine coolant was not added to the system
using the proper filling method.
Engine coolant is not within the specified
range.

Harness or connectors
(The cooling fan circuit is open or shorted.)
IPDM E/R
Cooling fan control module
Cooling fan motor
Radiator hose
Radiator
Radiator cap
Water pump
Thermostat

CAUTION:
When a malfunction is indicated, be sure to replace the coolant. Refer to CO-8, "Draining" and CO-9,
"Refilling". Also, replace the engine oil. Refer to LU-7, "Draining"and LU-8, "Refilling".
1. Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to MA-11, "Anti-Freeze Coolant Mixture Ratio".
2. After refilling coolant, run engine to ensure that no water-flow noise is emitted.

DTC CONFIRMATION PROCEDURE

1.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-384, "Component Function Check".
NOTE:
Use component function check to check the overall function of the cooling fan. During this check, a DTC might
not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-385, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734191

1.PERFORM COMPONENT FUNCTION CHECK-I

WARNING:
Never remove the radiator cap when the engine is hot. Serious burns could be caused by high pressure fluid escaping from the radiator.
Wrap a thick cloth around cap. Carefully remove the cap by turning it a quarter turn to allow built-up
pressure to escape. Then turn the cap all the way off.

Revision: 2007 June

EC-384

G37 Coupe

P1217 ENGINE OVER TEMPERATURE

< COMPONENT DIAGNOSIS >
Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
Is the coolant level in the reservoir tank and/or radiator below the
proper range?
YES >> Go to EC-385, "Diagnosis Procedure".
NO
>> GO TO 2.

[VQ37VHR]
A

EC

C
SEF621W

2.PERFORM COMPONENT FUNCTION CHECK-II

Confirm whether customer filled the coolant or not.

Did customer fill the coolant?
YES >> Go to EC-385, "Diagnosis Procedure".
NO
>> GO TO 3.

3.PERFORM COMPONENT FUNCTION CHECK-III

With CONSULT-III
Turn ignition switch ON.
Perform FAN DUTY CONTROL in ACTIVE TEST mode with CONSULT-III.
Make sure that cooling fan speed varies according to the percent.
Without CONSULT-III
Perform IPDM E/R auto active test and check cooling fan motors operation, refer to PCS-11, "Diagnosis
Description".
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-385, "Diagnosis Procedure".
1.
2.
3.

Diagnosis Procedure

INFOID:0000000001734192

1.CHECK COOLING FAN OPERATION

With CONSULT-III
Turn ignition switch ON.
Perform FAN DUTY CONTROL in ACTIVE TEST mode with CONSULT-III.
Make sure that cooling fan speed varies according to the percent.
Without CONSULT-III
1. Perform IPDM E/R auto active test and check cooling fan motors operation, refer to PCS-11, "Diagnosis
Description".
2. Make sure that cooling fan operates.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Go to EC-481, "Diagnosis Procedure".

1.
2.
3.

2.CHECK COOLING SYSTEM FOR LEAK-I

Check cooling system for leak. Refer to CO-8, "Inspection".
Is leakage detected?
YES >> GO TO 3.
NO
>> GO TO 4.

3.CHECK COOLING SYSTEM FOR LEAK-II

Check the following for leak.
Hose
Radiator
Water pump

Revision: 2007 June

EC-385

G37 Coupe

P1217 ENGINE OVER TEMPERATURE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> Repair or replace malfunctioning part.

4.CHECK RADIATOR CAP

Check radiator cap. Refer to CO-12, "RADIATOR CAP : Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Replace radiator cap.

5.CHECK THERMOSTAT
Check thermostat. Refer to CO-23, "Inspection".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace thermostat

6.CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to EC-186, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Replace engine coolant temperature sensor.

7.CHECK MAIN 12 CAUSES

If the cause cannot be isolated, check the following.
Engine

Step

Inspection item

OFF

Equipment

Standard

Reference page

Visual

No blocking

Coolant mixture

Coolant tester

50 - 50% coolant mixture

Coolant level

Visual

Coolant up to MAX level in

reservoir tank and radiator
filler neck

Radiator cap

Pressure tester

107 kPa

ON*2

Coolant leaks

Visual

No leaks

CO-8, "Inspection"

ON*2

Thermostat

Touch the upper and

lower radiator hoses

Both hoses should be hot

CO-23, "Inspection"

ON*1

Cooling fan

CONSULT-III

Operating

EC-481, "Component
Function Check"

OFF

Combustion gas leak

Color checker chemical

tester 4 Gas analyzer

Negative

ON*3

Coolant temperature
gauge

Visual

Gauge less than 3/4 when

driving

Coolant overflow to reservoir tank

Visual

No overflow during driving

and idling

CO-8, "Inspection"

Blocked radiator
Blocked condenser
Blocked radiator grille
Blocked bumper

CO-8, "Inspection"

CO-12, "RADIATOR CAP

(1.1 kg/cm2, 16 psi) (Limit) : Inspection"

OFF*4

10

Coolant return from reservoir tank to radiator

Visual

Should be initial level in

reservoir tank

CO-8, "Inspection"

OFF

11

Cylinder head

Straight gauge feeler

gauge

0.1 mm (0.004 in) Maximum distortion (warping)

EM-106, "Inspection"

12

Cylinder block and pistons

Visual

No scuffing on cylinder
walls or piston

EM-120, "Inspection"

*1: Turn the ignition switch ON.

*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.

Revision: 2007 June

EC-386

G37 Coupe

P1217 ENGINE OVER TEMPERATURE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

For more information, refer to CO-3, "Troubleshooting Chart".

>> INSPECTION END

EC

Revision: 2007 June

EC-387

G37 Coupe

P1225, P1234 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1225, P1234 TP SENSOR

Description

INFOID:0000000001910843

Electric throttle control actuator consists of throttle control motor,

throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

PBIB0145E

INFOID:0000000001734194

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

P1225

Closed throttle position learning performance (bank 1)

P1234

Closed throttle position learning performance (bank 2)

DTC detecting condition

Closed throttle position learning value
is excessively low.

Possible cause
Electric throttle control actuator
(TP sensor 1 and 2)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-388, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734195

1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.
2.

Turn ignition switch OFF.

Remove the intake air duct.

Revision: 2007 June

EC-388

G37 Coupe

P1225, P1234 TP SENSOR

< COMPONENT DIAGNOSIS >
3. Check if foreign matter is caught between the throttle valve (1)
and the housing.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Remove the foreign matter and clean the electric throttle
control actuator inside.

[VQ37VHR]
A

EC

C
JMBIA0025ZZ

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-389, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910847

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END
J

Revision: 2007 June

EC-389

G37 Coupe

P1226, P1235 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1226, P1235 TP SENSOR

Description

INFOID:0000000001910844

Electric throttle control actuator consists of throttle control motor,

throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

PBIB0145E

INFOID:0000000001734198

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

P1226

Closed throttle position learning performance (bank 1)

P1235

Closed throttle position learning performance (bank 2)

DTC detecting condition

Closed throttle position learning is not performed
successfully, repeatedly.

Possible cause
Electric throttle control actuator
(TP sensor 1 and 2)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Repeat steps 2 and 3 for 32 times.
5. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-390, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001911018

1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.
2.

Turn ignition switch OFF.

Remove the intake air duct.

Revision: 2007 June

EC-390

G37 Coupe

P1226, P1235 TP SENSOR

< COMPONENT DIAGNOSIS >
3. Check if foreign matter is caught between the throttle valve (1)
and the housing.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Remove the foreign matter and clean the electric throttle
control actuator inside.

[VQ37VHR]
A

EC

C
JMBIA0025ZZ

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-391, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910848

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END
J

Revision: 2007 June

EC-391

G37 Coupe

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

Description

INFOID:0000000001734201

Electric throttle control actuator consists of throttle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feedback to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.

DTC Logic

INFOID:0000000001734202

DTC DETECTION LOGIC

NOTE:
If DTC P1233 or P2101 is displayed with DTC P1238, P1290, P2100 or 2119, first perform the trouble
diagnosis for DTC P1238, P2119 or P1290, P2100. Refer to EC-399, "DTC Logic" or EC-404, "DTC
Logic".
DTC No.

Trouble diagnosis name

P1233

Electric throttle control

performance (bank 2)

P2101

Electric throttle control

performance (bank 1)

DTC detecting condition

Electric throttle control function does not operate properly.

Possible cause
Harness or connectors
(Throttle control motor circuit is open or
shorted)
Electric throttle control actuator

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V when engine
is running.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 2 seconds.
2. Start engine and let it idle for 5 seconds.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-392, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734203

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I

Check the voltage between ECM harness connector and ground.

Revision: 2007 June

EC-392

G37 Coupe

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ECM

DTC

Connector

Terminal

F102

52

P1233

Ground

Ground
P2101

F101

Condition

Voltage

Ignition switch OFF

Approx. 0V

Ignition switch ON

Battery voltage

Ignition switch OFF

Approx. 0V

Ignition switch ON

Battery voltage

EC

Is the inspection result normal?

YES >> GO TO 9.
NO
>> GO TO 3.

3.CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Disconnect IPDM E/R harness connector E7.
Check the continuity between IPDM E/R harness connector and ECM harness connector.
IPDM E/R

ECM

Connector

Terminal

Connector

Terminal

E7

70

F101

25

Continuity

G
Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E3, F1
Harness connectors F104, F105
Harness for open or short between ECM and IPDM E/R

>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II

1.

Check the continuity between IPDM E/R harness connector and ECM harness connector.

DTC

IPDM E/R

ECM

Connector

Terminal

E7

54

P1233
P2101

Connector

Terminal

F102

52

F101

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E3, F1
Harness for open or short between ECM and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK FUSE
Revision: 2007 June

EC-393

G37 Coupe

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

1. Disconnect 15A fuse (No. 51) from IPDM E/R.
2. Check 15A fuse for blown.
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace 15A fuse.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair or replace harness or connectors.

9.CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect electric throttle control actuator harness connector.
Disconnect ECM harness connector.
Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

ECM
Connector

5
P1233

F27

F102
6

1
P2101

F6

F101
2

Terminal

Continuity

49

Existed

50

Not existed

49

Not existed

50

Existed

Existed

Not existed

Not existed

Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 10.
NO
>> Repair or replace.

10.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.
2.

Remove the intake air duct.

Check if foreign matter is caught between the throttle valve (1)
and the housing.
Is the inspection result normal?
YES >> GO TO 11.
NO
>> Remove the foreign matter and clean the electric throttle
control actuator inside.

JMBIA0025ZZ

11.CHECK THROTTLE CONTROL MOTOR

Refer to EC-395, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 12.
NO
>> GO TO 13.

12.CHECK INTERMITTENT INCIDENT

Revision: 2007 June

EC-394

G37 Coupe

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

< COMPONENT DIAGNOSIS >
Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 13.
NO
>> Repair or replace harness or connectors.

[VQ37VHR]
A

13.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

EC

Replace malfunction electric throttle control actuator.

Go to EC-395, "Special Repair Requirement".

>> INSPECTION END

Component Inspection

INFOID:0000000001734204

1.CHECK THROTTLE CONTROL MOTOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect electric throttle control actuator harness connector.
Check resistance between electric throttle control actuator terminals as follows.

F
Electric throttle control actuator
Bank

Terminals

1 and 2

5 and 6

Resistance

G
Approx. 1 - 15 [at 25C (77F)]

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-395, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910849

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END
O

Revision: 2007 June

EC-395

G37 Coupe

P1236, P2118 THROTTLE CONTROL MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1236, P2118 THROTTLE CONTROL MOTOR

Description

INFOID:0000000001734206

The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feedback to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.

DTC Logic

INFOID:0000000001734207

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

P1236

Throttle control motor

(bank 2) circuit short

P2118

Throttle control motor

(bank 1) circuit short

DTC detecting condition

ECM detects short in both circuits between
ECM and throttle control motor.

Possible cause
Harness or connectors
(Throttle control motor circuit is shorted.)
Electric throttle control actuator
(Throttle control motor)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 2 seconds.
2. Start engine and let it idle for 5 seconds.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-396, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734208

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Disconnect electric throttle control actuator harness connector.

Disconnect ECM harness connector.
Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

Revision: 2007 June

EC-396

G37 Coupe

P1236, P2118 THROTTLE CONTROL MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

Electric throttle control actuator

Bank

Connector

Terminal

Connector

5
P1236

F27

F102
6

1
P2118

ECM

F6

F101
2

Continuity

Terminal
49

Existed

50

Not existed

49

Not existed

50

Existed

Existed

Not existed

Not existed

Existed

EC

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.CHECK THROTTLE CONTROL MOTOR

Refer to EC-397, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> GO TO 5.

4.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair or replace harness or connectors.

5.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-398, "Special Repair Requirement".

>> INSPECTION END

L

Component Inspection

INFOID:0000000001911020

1.CHECK THROTTLE CONTROL MOTOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect electric throttle control actuator harness connector.
Check resistance between electric throttle control actuator terminals as follows.
Electric throttle control actuator
Bank

Terminals

1 and 2

5 and 6

Resistance

O
Approx. 1 - 15 [at 25C (77F)]

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-398, "Special Repair Requirement".

Revision: 2007 June

EC-397

G37 Coupe

P1236, P2118 THROTTLE CONTROL MOTOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910850

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"
>> END

Revision: 2007 June

EC-398

G37 Coupe

P1238, P2119 ELECTRIC THROTTLE CONTROL ACTUATOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1238, P2119 ELECTRIC THROTTLE CONTROL ACTUATOR

Description

A
INFOID:0000000001734211

Electric throttle control actuator consists of throttle control motor, throttle position sensor, etc.
EC
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The throttle position sensor detects the throttle valve position, and the opening and closing speed of the throttle valve and feeds the voltage signals to the ECM. The ECM judges the current opening angle of the throttle
valve from these signals and the ECM controls the throttle control motor to make the throttle valve opening C
angle properly in response to driving condition.

DTC Logic

INFOID:0000000001734212

DTC DETECTION LOGIC

E
DTC No.

P1238

P2119

Trouble diagnosis name

Electric throttle control

actuator (bank 2)

Electric throttle control

actuator (bank 1)

DTC detecting condition

A)

Electric throttle control actuator does not function properly due to the return spring malfunction.

B)

Throttle valve opening angle in fail-safe mode is

not in specified range.

C)

ECM detect the throttle valve is stuck open.

A)

Electric throttle control actuator does not function properly due to the return spring malfunction.

B)

Throttle valve opening angle in fail-safe mode is

not in specified range.

C)

ECM detect the throttle valve is stuck open.

Possible cause

G
Electric throttle control actuator

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A AND B

1. Turn ignition switch ON and wait at least 1 second.

2. Shift selector lever to D position (A/T) or 1st position (M/T) and wait at least 3 seconds.
3. Shift selector lever to P position (A/T) or Neutral position (M/T).
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON and wait at least 1 second.
6. Shift selector lever to D position (A/T) or 1st position (M/T) and wait at least 3 seconds.
7. Shift selector lever to P position (A/T) or Neutral position (M/T).
8. Turn ignition switch OFF, wait at least 10 seconds, and then turn ON.
9. Check DTC.
Is DTC detected?
YES >> Go to EC-400, "Diagnosis Procedure".
NO
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION C

1.
2.
3.

Turn ignition switch ON and wait at least 1 second.

Shift selector lever to D position (A/T) or 1st position (M/T) and wait at least 3 seconds.
Shift selector lever to P position (A/T) or Neutral position (M/T).

Revision: 2007 June

EC-399

G37 Coupe

P1238, P2119 ELECTRIC THROTTLE CONTROL ACTUATOR

< COMPONENT DIAGNOSIS >
4. Start engine and let it idle for 3 seconds.
5. Check DTC.
Is DTC detected?
YES >> Go to EC-400, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

[VQ37VHR]

INFOID:0000000001911019

1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.
2.
3.

Turn ignition switch OFF.

Remove the intake air duct.
Check if foreign matter is caught between the throttle valve (1)
and the housing.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Remove the foreign matter and clean the electric throttle
control actuator inside.

JMBIA0025ZZ

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-400, "Special Repair Requirement".
>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910851

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"
>> END

Revision: 2007 June

EC-400

G37 Coupe

P1239, P2135 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1239, P2135 TP SENSOR

Description

INFOID:0000000001910845

Electric throttle control actuator consists of throttle control motor,

throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

EC

PBIB0145E

DTC Logic

INFOID:0000000001734216

DTC DETECTION LOGIC

NOTE:
If DTC P1239 or P2135 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-358, "DTC Logic".

DTC No.

Trouble diagnosis name

P1239

Throttle position sensor

(bank 2) circuit range/
performance

P2135

Throttle position sensor

(bank 1) circuit range/
performance

DTC detecting condition

Possible cause

H
Rationally incorrect voltage is sent to ECM
compared with the signals from TP sensor 1
and TP sensor 2.

Harness or connector
(TP sensor 1 and 2 circuit is open or
shorted.)
Electric throttle control actuator
(TP sensor 1 and 2)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-401, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734217

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
Revision: 2007 June

EC-401

G37 Coupe

P1239, P2135 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> Repair or replace ground connection.

2.CHECK THROTTLE POSITION SENSOR POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect electric throttle control actuator harness connector.

Turn ignition switch ON.
Check the voltage between electric throttle control actuator harness connector and ground.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

P1239

F27

P2135

F6

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK THROTTLE POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

DTC

Electric throttle control actuator

Bank

Connector

Terminal

P1239

F27

P2135

F6

ECM
Connector

Terminal

Continuity

48

F101

Existed

40

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK THROTTLE POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

DTC

P1239

P2135

Electric throttle control actuator

Bank

Connector

F27

F6

Terminal

ECM
Connector

2
3
4

Terminal

Continuity

31
F101

35
30

Existed

34

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK THROTTLE POSITION SENSOR

Refer to EC-403, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.

Replace malfunctioning electric throttle control actuator.

Revision: 2007 June

EC-402

G37 Coupe

P1239, P2135 TP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2. EC-403, "Special Repair Requirement".

>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

EC

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001910846

1.CHECK THROTTLE POSITION SENSOR

1.
2.
3.
4.
5.
6.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Perform EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
Turn ignition switch ON.
Set selector lever to D (A/T) or 1st (M/T) position.
Check the voltage between ECM harness connector and ground.

ECM
Connector

Terminal

Ground

Condition

30 [TP sensor 1 (bank 1)]

31 [TP sensor 1 (bank 2)]
F101

Ground

Accelerator pedal

34 [TP sensor 2 (bank 1)]

35 [TP sensor 2 (bank 2)]

Voltage

Fully released

More than 0.36V

Fully depressed

Less than 4.75V

Fully released

Less than 4.75V

Fully depressed

More than 0.36V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.
2.

Replace malfunctioning electric throttle control actuator.

Go to EC-403, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910852

1.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"
N

>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END
P

Revision: 2007 June

EC-403

G37 Coupe

P1290, P2100, P2103 THROTTLE CONTROL MOTOR RELAY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1290, P2100, P2103 THROTTLE CONTROL MOTOR RELAY

Description

INFOID:0000000001734220

Power supply for the throttle control motor is provided to the ECM via throttle control motor relay. The throttle
control motor relay is ON/OFF controlled by the ECM. When the ignition switch is turned ON, the ECM sends
an ON signal to throttle control motor relay and battery voltage is provided to the ECM. When the ignition
switch is turned OFF, the ECM sends an OFF signal to throttle control motor relay and battery voltage is not
provided to the ECM.

DTC Logic

INFOID:0000000001734221

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

P1290

Throttle control motor relay

circuit open (bank 2)

P2100

Throttle control motor relay

circuit open (bank 1)

P2103

Throttle control motor relay

circuit short

DTC detecting condition

Possible cause

ECM detects a voltage of power source for

throttle control motor is excessively low.

Harness or connectors
(Throttle control motor relay circuit is
open)
Throttle control motor relay

ECM detect the throttle control motor relay is

stuck ON.

Harness or connectors
(Throttle control motor relay circuit is
shorted)
Throttle control motor relay

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V.
Which DTC is detected?
P1290, P2100>>GO TO 2.
P2103 >> GO TO 3.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P1290 AND P2100

1. Turn ignition switch ON and wait at least 2 seconds.
2. Start engine and let it idle for 5 seconds.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-404, "Diagnosis Procedure".
NO
>> INSPECTION END

3.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P2103

1. Turn ignition switch ON and wait at least 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-404, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734222

1.CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT

1.
2.

Turn ignition switch OFF.

Disconnect ECM harness connector.

Revision: 2007 June

EC-404

G37 Coupe

P1290, P2100, P2103 THROTTLE CONTROL MOTOR RELAY

< COMPONENT DIAGNOSIS >
3. Disconnect IPDM E/R harness connector E7.
4. Check the continuity between IPDM E/R harness connector and ECM harness connector.
IPDM E/R

ECM

Connector

Terminal

Connector

Terminal

E7

70

F101

25

[VQ37VHR]
A

Continuity

EC

Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 3.
NO
>> GO TO 2.

2.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
Harness connectors F104, F105
Harness for open or short between ECM and IPDM E/R

>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT

1.

Check the continuity between IPDM E/R sensor harness connector and ECM harness connector.

DTC

IPDM E/R
Connector

ECM

Terminal

P1290
P2100

E7

P2103

54

Connector

Terminal

F102

52

F101

F101

F102

52

Continuity

I
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E3, F1
Harness for open or short between ECM and IPDM E/R

>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK FUSE

1. Disconnect 15A fuse (No. 51) from IPDM E/R.

2. Check 15A fuse for blown.
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace 15A fuse.

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair or replace harness or connectors.

Revision: 2007 June

EC-405

G37 Coupe

P1421 COLD START CONTROL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1421 COLD START CONTROL

Description

INFOID:0000000001734223

ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.

DTC Logic

INFOID:0000000001734224

DTC DETECTION LOGIC

NOTE:
If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
DTC No.
P1421

Trouble diagnosis name

Cold start emission reduction
strategy monitoring

DTC detecting condition

ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.

Possible cause
Lack of intake air volume
Fuel injection system
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Select DATA MONITOR mode with CONSULT-III.
Check the indication of COOLAN TEMP/S.
If it is between 4C (39F) and 36C (97F), go to the following steps.
If it is below 4C (39F), warm engine up to more than 4C (39F) and retry from step 1.
If it is above 36C (97F), cool engine down to less than 36C (97F) and retry from step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-406, "Diagnosis Procedure".
NO
>> INSPECTION END
1.
2.
3.
4.

Diagnosis Procedure

INFOID:0000000001734225

1.PERFORM IDLE AIR VOLUME LEARNING

Perform EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 2.
NO
>> Follow the instruction of Idle Air Volume Learning.

2.CHECK INTAKE SYSTEM

Revision: 2007 June

EC-406

G37 Coupe

P1421 COLD START CONTROL

< COMPONENT DIAGNOSIS >
Check for the cause of intake air volume lacking. Refer to the following.
Crushed intake air passage
Intake air passage clogging
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace malfunctioning part

[VQ37VHR]
A

EC

3.CHECK FUEL INJECTION SYSTEM FUNCTION

C

Perform DTC Confirmation Procedure for DTC P0171, P0174. Refer to EC-232, "DTC Logic".
Is the inspection result normal?
YES >> GO TO 4.
NO
>> Go to EC-233, "Diagnosis Procedure" for DTC P0171, P0174.

4.PERFORM DTC CONFIRMATION PROCEDURE

E

With CONSULT-III
1. Turn ignition switch ON.
2. Select SELF DIAG RESULTS mode with CONSULT-III.
3. Touch ERASE.
4. Perform DTC Confirmation Procedure.
See EC-406, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-406, "DTC Logic".
Is the 1st trip DTC P1421 displayed again?
YES >> GO TO 5.
NO
>> INSPECTION END

5.REPLACE ECM
1.
2.

Replace ECM.
Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".

>> INSPECTION END

Revision: 2007 June

EC-407

G37 Coupe

P1550 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1550 BATTERY CURRENT SENSOR

Description

INFOID:0000000001734226

The power generation voltage variable control enables fuel consumption to be decreased by reducing the
engine load which is caused by the power generation of the generator. The battery current sensor is installed
to the battery cable at the negative terminal. The sensor measures the charging/discharging current of the battery. Based on the sensor signal, ECM judges whether or not the power generation voltage variable control is
performed. When performing the power generation voltage variable control, ECM calculates the target power
generation voltage based on the sensor signal. And ECM sends the calculated value as the power generation
command value to IPDM E/R. For the details of the power generation voltage variable control, refer to CHG-8,
"System Description".
CAUTION:
Do not connect the electrical component or the ground wire directly to the battery terminal. The connection causes the malfunction of the power generation voltage variable control, and then the battery
discharge may occur.

DTC Logic

INFOID:0000000001734227

DTC DETECTION LOGIC

NOTE:
If DTC P1550 is displayed with DTC P0643, first perform the trouble diagnosis for P0643. Refer to EC-358,
"DTC Logic".
DTC No.

P1550

Trouble diagnosis name

Battery current sensor circuit
range/performance

DTC detecting condition

Possible cause

The output voltage of the battery current

sensor remains within the specified
range while engine is running.

Harness or connectors
(Battery current sensor circuit is open
or shorted.)
Battery current sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and wait at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-408, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734228

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.
Revision: 2007 June

EC-408

G37 Coupe

P1550 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect battery current sensor harness connector.

Turn ignition switch ON.
Check the voltage between battery current sensor harness connector and ground.
Battery current sensor

Connector

Terminal

E21

Ground

EC

Voltage

C
Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 3.

3.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

64

Continuity

G
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness connectors.

5.CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

95

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
Revision: 2007 June

EC-409

G37 Coupe

P1550 BATTERY CURRENT SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Check the continuity between battery current sensor harness connector and ECM harness connector.
Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

91

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK BATTERY CURRENT SENSOR

Refer to EC-410, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace battery negative cable assembly.

10.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734229

1.CHECK BATTERY CURRENT SENSOR

1.
2.
3.

Turn ignition switch OFF.

Reconnect harness connectors disconnected.
Disconnect battery negative cable (1).
: To body ground

4.
5.
6.

Install jumper cable (A) between battery negative terminal and

body ground.
Turn ignition switch ON.
Check the voltage between ECM harness connector and
ground.
ECM

Connector

Terminal

F102

91
(Battery current sensor signal)

Ground

Voltage

Ground

Approx. 2.5V

JMBIA0027ZZ

Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to PG-3, "How to Handle Battery".

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace battery negative cable assembly.

Revision: 2007 June

EC-410

G37 Coupe

P1551, P1552 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1551, P1552 BATTERY CURRENT SENSOR

Description

INFOID:0000000001911021

The power generation voltage variable control enables fuel consumption to be decreased by reducing the EC
engine load which is caused by the power generation of the generator. The battery current sensor is installed
to the battery cable at the negative terminal. The sensor measures the charging/discharging current of the battery. Based on the sensor signal, ECM judges whether or not the power generation voltage variable control is
performed. When performing the power generation voltage variable control, ECM calculates the target power C
generation voltage based on the sensor signal. And ECM sends the calculated value as the power generation
command value to IPDM E/R. For the details of the power generation voltage variable control, refer to CHG-8,
"System Description".
D
CAUTION:
Do not connect the electrical component or the ground wire directly to the battery terminal. The connection causes the malfunction of the power generation voltage variable control, and then the battery
E
discharge may occur.

DTC Logic

INFOID:0000000001734231

DTC DETECTION LOGIC

NOTE:
If DTC P1551 or P1552 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer
to EC-358, "DTC Logic".
DTC No.

DTC detecting condition

Possible cause

P1551

Battery current sensor circuit

low input

Trouble diagnosis name

An excessively low voltage from the sensor is sent to ECM.

P1552

Battery current sensor circuit

high input

An excessively high voltage from the sensor is sent to ECM.

Harness or connectors
(Battery current sensor circuit is open
or shorted.)
Battery current sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V with ignition
switch ON

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

N

1. Turn ignition switch ON and wait at least 10 seconds.

2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-411, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001911024

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
Revision: 2007 June

EC-411

G37 Coupe

P1551, P1552 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> Repair or replace ground connection.

2.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect battery current sensor harness connector.

Turn ignition switch ON.
Check the voltage between battery current sensor harness connector and ground.
Battery current sensor

Connector

Terminal

E21

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 3.

3.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

64

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness connectors.

5.CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

95

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

Revision: 2007 June

EC-412

G37 Coupe

P1551, P1552 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

7.CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

91

EC

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

E

Check the following.

Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK BATTERY CURRENT SENSOR

Refer to EC-419, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace battery negative cable assembly.

10.CHECK INTERMITTENT INCIDENT

I

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001911025

1.CHECK BATTERY CURRENT SENSOR

1.
2.
3.

Turn ignition switch OFF.

Reconnect harness connectors disconnected.
Disconnect battery negative cable (1).
: To body ground

4.
5.
6.

Install jumper cable (A) between battery negative terminal and

body ground.
Turn ignition switch ON.
Check the voltage between ECM harness connector and
ground.
ECM

Connector

Terminal

F102

91
(Battery current sensor signal)

Ground

Voltage

Ground

Approx. 2.5V

JMBIA0027ZZ

Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to PG-3, "How to Handle Battery".

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace battery negative cable assembly.

Revision: 2007 June

EC-413

G37 Coupe

P1553 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1553 BATTERY CURRENT SENSOR

Description

INFOID:0000000001911022

The power generation voltage variable control enables fuel consumption to be decreased by reducing the
engine load which is caused by the power generation of the generator. The battery current sensor is installed
to the battery cable at the negative terminal. The sensor measures the charging/discharging current of the battery. Based on the sensor signal, ECM judges whether or not the power generation voltage variable control is
performed. When performing the power generation voltage variable control, ECM calculates the target power
generation voltage based on the sensor signal. And ECM sends the calculated value as the power generation
command value to IPDM E/R. For the details of the power generation voltage variable control, refer to CHG-8,
"System Description".
CAUTION:
Do not connect the electrical component or the ground wire directly to the battery terminal. The connection causes the malfunction of the power generation voltage variable control, and then the battery
discharge may occur.

DTC Logic

INFOID:0000000001734235

DTC DETECTION LOGIC

NOTE:
If DTC P1553 is displayed with DTC P0643, first perform the trouble diagnosis for P0643. Refer to EC-358,
"DTC Logic".
DTC No.

P1553

Trouble diagnosis name

Battery current sensor performance

DTC detecting condition

Possible cause

The signal voltage transmitted from the

sensor to ECM is higher than the amount
of the maximum power generation.

Harness or connectors
(Battery current sensor circuit is open
or shorted.)
Battery current sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and wait at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-414, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001911026

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.
Revision: 2007 June

EC-414

G37 Coupe

P1553 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

2.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect battery current sensor harness connector.

Turn ignition switch ON.
Check the voltage between battery current sensor harness connector and ground.
Battery current sensor

Connector

Terminal

E21

Ground

EC

Voltage

C
Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 3.

3.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

64

Continuity

G
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness connectors.

5.CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

95

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
Revision: 2007 June

EC-415

G37 Coupe

P1553 BATTERY CURRENT SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Check the continuity between battery current sensor harness connector and ECM harness connector.
Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

91

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK BATTERY CURRENT SENSOR

Refer to EC-419, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace battery negative cable assembly.

10.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001911027

1.CHECK BATTERY CURRENT SENSOR

1.
2.
3.

Turn ignition switch OFF.

Reconnect harness connectors disconnected.
Disconnect battery negative cable (1).
: To body ground

4.
5.
6.

Install jumper cable (A) between battery negative terminal and

body ground.
Turn ignition switch ON.
Check the voltage between ECM harness connector and
ground.
ECM

Connector

Terminal

F102

91
(Battery current sensor signal)

Ground

Voltage

Ground

Approx. 2.5V

JMBIA0027ZZ

Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to PG-3, "How to Handle Battery".

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace battery negative cable assembly.

Revision: 2007 June

EC-416

G37 Coupe

P1554 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1554 BATTERY CURRENT SENSOR

Description

A
INFOID:0000000001911023

The power generation voltage variable control enables fuel consumption to be decreased by reducing the EC
engine load which is caused by the power generation of the generator. The battery current sensor is installed
to the battery cable at the negative terminal. The sensor measures the charging/discharging current of the battery. Based on the sensor signal, ECM judges whether or not the power generation voltage variable control is
performed. When performing the power generation voltage variable control, ECM calculates the target power C
generation voltage based on the sensor signal. And ECM sends the calculated value as the power generation
command value to IPDM E/R. For the details of the power generation voltage variable control, refer to CHG-8,
"System Description".
D
CAUTION:
Do not connect the electrical component or the ground wire directly to the battery terminal. The connection causes the malfunction of the power generation voltage variable control, and then the battery
E
discharge may occur.

DTC Logic

INFOID:0000000001734239

DTC DETECTION LOGIC

NOTE:
If DTC P1554 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to EC358, "DTC Logic".
DTC No.

P1554

Trouble diagnosis name

Battery current sensor performance

DTC detecting condition

Possible cause

The output voltage of the battery current

sensor is lower than the specified value
while the battery voltage is high enough.

Harness or connectors
(Battery current sensor circuit is open
or shorted.)
Battery current sensor

DTC CONFIRMATION PROCEDURE

1.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-417, "Component Function Check".

NOTE:
Use component function check to check the overall function of the battery current sensor circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-418, "Diagnosis Procedure".

Component Function Check

INFOID:0000000001734240

1.PRECONDITIONING
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 12.8V at idle.
Before performing the following procedure, confirm that all load switches and A/C switch are turned
OFF.

>> GO TO 2.

2.PERFORM COMPONENT FUNCTION CHECK

With CONSULT-III
1. Start engine and let it idle.
2. Select BAT CUR SEN in DATA MONITOR mode with CONSULT-III.
3. Check BAT CUR SEN indication for 10 seconds.
BAT CUR SEN should be above 2,300mV at least once.
Without CONSULT-III
1. Start engine and let it idle.
Revision: 2007 June

EC-417

G37 Coupe

P1554 BATTERY CURRENT SENSOR

< COMPONENT DIAGNOSIS >
2. Check the voltage between ECM harness connector and ground.
ECM
Connector

Terminal

F102

91
(Battery current sensor signal)

Ground

Voltage

Ground

Above 2.3V at least once

[VQ37VHR]

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-418, "Diagnosis Procedure"

Diagnosis Procedure

INFOID:0000000001911028

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect battery current sensor harness connector.

Turn ignition switch ON.
Check the voltage between battery current sensor harness connector and ground.
Battery current sensor

Connector

Terminal

E21

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 3.

3.CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between battery current sensor harness connector and ECM harness connector.

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

64

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness connectors.

5.CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.

Turn ignition switch OFF.

Disconnect ECM harness connector.

Revision: 2007 June

EC-418

G37 Coupe

P1554 BATTERY CURRENT SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
3. Check the continuity between battery current sensor harness connector and ECM harness connector.
A
Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

95

Continuity

EC

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between battery current sensor harness connector and ECM harness connector.
G

Battery current sensor

ECM

Connector

Terminal

Connector

Terminal

E21

F102

91

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors F1, E3
Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK BATTERY CURRENT SENSOR

Refer to EC-419, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace battery negative cable assembly.

10.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

O

>> INSPECTION END

Component Inspection

INFOID:0000000001911029

1.CHECK BATTERY CURRENT SENSOR

1.
2.

Turn ignition switch OFF.

Reconnect harness connectors disconnected.

Revision: 2007 June

EC-419

G37 Coupe

P1554 BATTERY CURRENT SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

3. Disconnect battery negative cable (1).
: To body ground

4.
5.
6.

Install jumper cable (A) between battery negative terminal and

body ground.
Turn ignition switch ON.
Check the voltage between ECM harness connector and
ground.
ECM

Connector

Terminal

F102

91
(Battery current sensor signal)

Ground

Voltage

Ground

Approx. 2.5V

JMBIA0027ZZ

Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to PG-3, "How to Handle Battery".

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace battery negative cable assembly.

Revision: 2007 June

EC-420

G37 Coupe

P1564 ASCD STEERING SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1564 ASCD STEERING SWITCH

Description

INFOID:0000000001734243

ASCD steering switch has variant values of electrical resistance for each button. ECM reads voltage variation EC
of switch, and determines which button is operated.
Refer to EC-62, "System Description" for the ASCD function.

DTC Logic

INFOID:0000000001734244

NOTE:
If DTC P1564 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer to
EC-356, "DTC Logic".

DTC DETECTION LOGIC

DTC No.

P1564

Trouble diagnosis
name

DTC detecting condition

ASCD steering switch

An excessively high voltage signal from the

ASCD steering switch is sent to ECM.
ECM detects that input signal from the
ASCD steering switch is out of the specified
range.
ECM detects that the ASCD steering switch
is stuck ON.

Possible cause

Harness or connectors
(The switch circuit is open or shorted.)
ASCD steering switch
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.

Turn ignition switch ON and wait at least 10 seconds.

Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.
Press CANCEL switch for at least 10 seconds, then release it and wait at least 10 seconds.
Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 seconds.
5. Press SET/COAST switch for at least 10 seconds, then release it and wait at least 10 seconds.
6. Check DTC.
Is DTC detected?
YES >> Go to EC-421, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734245

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK ASCD STEERING SWITCH CIRCUIT

With CONSULT-III
Revision: 2007 June

EC-421

G37 Coupe

P1564 ASCD STEERING SWITCH

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Turn ignition switch ON.
2. Select MAIN SW, CANCEL SW, RESUME/ACC SW and SET SW in DATA MONITOR mode with
CONSULT-III.
3. Check each item indication under the following conditions.
Monitor item

Condition

MAIN SW

MAIN switch

CANCEL SW

CANCEL switch

RESUME/ACC SW

RESUME/ACCELERATE switch

SET SW

SET/COAST switch

1.
2.

Indication
Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Without CONSULT-III
Turn ignition switch ON.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Ground

Terminal

101
(ASCD steering switch signal)

M107

Ground

Condition

Voltage

MAIN switch: Pressed

Approx. 0V

CANCEL switch: Pressed

Approx. 1V

SET/COAST switch: Pressed

Approx. 2V

RESUME/ACCELERATE switch: Pressed

Approx. 3V

All ASCD steering switches: Released

Approx. 4V

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 3.

3.CHECK ASCD STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Disconnect combination switch harness connector M303.
Check the continuity between combination switch and ECM harness connector.

Combination switch

ECM

Terminal

Connector

Terminal

16

M107

108

Continuity
Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Combination switch (spiral cable)
Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK ASCD STEERING SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between combination switch and ECM harness connector.

Revision: 2007 June

EC-422

G37 Coupe

P1564 ASCD STEERING SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Combination switch

ECM

Terminal

Connector

Terminal

13

M107

101

Continuity
Existed

EC

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

D

Check the following.

Combination switch (spiral cable)
Harness for open and short between ECM and combination switch

>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK ASCD STEERING SWITCH

Refer to EC-423, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace ASCD steering switch.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001734246

1.CHECK ASCD STEERING SWITCH

1.
2.
3.

Turn ignition switch OFF.

Disconnect combination switch (spiral cable) harness connector M303.
Check resistance between combination switch harness connector terminals under the following conditions.
Combination switch

Connector

Terminals

L
Condition

Resistance
Approx. 0

MAIN switch: Pressed

M303

13 and 16

CANCEL switch: Pressed

Approx. 250

SET/COAST switch: Pressed

Approx. 660

RESUME/ACCELERATE switch: Pressed

Approx. 1,480

All ASCD steering switches: Released

Approx. 4,000

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ASCD steering switch

Revision: 2007 June

EC-423

G37 Coupe

P1564 ICC STEERING SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1564 ICC STEERING SWITCH

Description

INFOID:0000000001734247

ICC steering switch has variant values of electrical resistance for each button. ECM reads voltage variation of
switch, and determines which button is operated.
Refer to CCS-15, "System Description" for the ICC function.

DTC Logic

INFOID:0000000001734248

DTC DETECTION LOGIC

NOTE:
If DTC P1564 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer to
EC-356, "DTC Logic".
DTC No.

P1564

Trouble diagnosis
name

ICC steering switch

DTC detecting condition

An excessively high voltage signal from the
ICC steering switch is sent to ECM.
ECM detects that input signal from the ICC
steering switch is out of the specified range.
ECM detects that the ICC steering switch is
stuck ON.

Possible cause

Harness or connectors
(The switch circuit is open or shorted.)
ICC steering switch
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.
4.

Turn ignition switch ON and wait at least 10 seconds.

Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.
Press CANCEL switch for at least 10 seconds, then release it and wait at least 10 seconds.
Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 seconds.
5. Press SET/COAST switch for at least 10 seconds, then release it and wait at least 10 seconds.
6. Press DISTANCE switch for at least 10 seconds, then release it and wait at least 10 seconds.
7. Check DTC.
Is DTC detected?
YES >> Go to EC-424, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734249

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK ICC STEERING SWITCH CIRCUIT

With CONSULT-III
Revision: 2007 June

EC-424

G37 Coupe

P1564 ICC STEERING SWITCH

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Turn ignition switch ON.
2. Select MAIN SW, CANCEL SW, RESUME/ACC SW, SET SW and DIST SW in DATA MONITOR
mode with CONSULT-III.
3. Check each item indication under the following conditions.

EC
Monitor item

Condition

MAIN SW

MAIN switch

CANCEL SW

CANCEL switch

RESUME/ACC SW

RESUME/ACCELERATE switch

SET SW

SET/COAST switch

DIST SW

DISTANCE switch

1.
2.

Indication
Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Pressed

ON

Released

OFF

Without CONSULT-III
Turn ignition switch ON.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Ground

Terminal

Condition
MAIN switch: Pressed

101
(ICC steering switch signal)

M107

Ground

Voltage
Approx. 0V

CANCEL switch: Pressed

Approx. 1.3V

DISTANCE switch: Pressed

Approx. 2.2V

SET/COAST switch: Pressed

Approx. 3.0V

RESUME/ACCELERATE switch: Pressed

Approx. 3.7V

All ICC steering switches: Released

Approx. 4.3V

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 3.

3.CHECK ICC STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Disconnect combination switch harness connector M303.
Check the continuity between combination switch and ECM harness connector.

Combination switch

ECM

Terminal

Connector

Terminal

16

M107

108

Continuity
Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Combination switch (spiral cable)
Harness for open and short between ECM and combination switch

Revision: 2007 June

EC-425

G37 Coupe

P1564 ICC STEERING SWITCH

< COMPONENT DIAGNOSIS >
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]

5.CHECK ICC STEERING SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between combination switch and ECM harness connector.

Combination switch

ECM

Terminal

Connector

Terminal

13

M107

101

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Combination switch (spiral cable)
Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK ICC STEERING SWITCH

Refer to EC-426, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Replace ICC steering switch.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734250

1.CHECK ICC STEERING SWITCH

1.
2.
3.

Turn ignition switch OFF.

Disconnect combination switch (spiral cable) harness connector M303.
Check resistance between combination switch harness connector terminals under the following conditions.
Combination switch

Connector

Terminals

Condition

Resistance
Approx. 0

MAIN switch: Pressed

M303

13 and 16

CANCEL switch: Pressed

Approx. 310

DISTANCE switch: Pressed

Approx. 740

SET/COAST switch: Pressed

Approx. 1,400

RESUME/ACCELERATE switch: Pressed

Approx. 2,600

All ICC steering switches: Released

Approx. 5,500

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ICC steering switch

Revision: 2007 June

EC-426

G37 Coupe

P1568 ICC FUNCTION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1568 ICC FUNCTION

DTC Logic

INFOID:0000000001734251

DTC DETECTION LOGIC

EC

NOTE:
If DTC P1568 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146, "DTC Logic".
If DTC P1568 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
If DTC P1568 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-356, "DTC Logic".
DTC No.

P1568

Trouble Diagnosis
Name

ICC function

DTC Detecting Condition

ECM detects a difference between signals

from ICC sensor integrated unit is out of specified range.

Possible Cause

Harness or connectors
(The CAN communication line is open or
shorted.)
ICC sensor integrated unit
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Step 4 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.
3.

Turn ignition switch ON.

Press MAIN switch on ICC steering switch.
Drive the vehicle at more than 40 km/h (25 MPH).
CAUTION:
Always drive vehicle at a safe speed.
4. Press SET/COAST switch.
5. Check DTC.
Is DTC detected?
YES >> Go to EC-427, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

N
INFOID:0000000001734252

1.REPLACE ICC SENSOR INTEGRATED UNIT

1.
2.
3.

Replace ICC sensor integrated unit.

Perform CCS-11, "ACTION TEST : Special Repair Requirement (Vehicle-To-Vehicle Distance Control
Mode)".
Check DTC of ICC sensor integrated unit. Refer to CCS-22, "Diagnosis Description".
>> INSPECTION END

Revision: 2007 June

EC-427

G37 Coupe

P1572 ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1572 ASCD BRAKE SWITCH

Description

INFOID:0000000001734253

When the brake pedal is depressed, ASCD brake switch is turned OFF and stop lamp switch is turned ON.
ECM detects the state of the brake pedal by this input of two kinds (ON/OFF signal).
Refer to EC-62, "System Description" for the ASCD function.

DTC Logic

INFOID:0000000001734254

DTC DETECTION LOGIC

NOTE:
If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-356, "DTC Logic".
This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two
consecutive trips, DTC is not stored in ECM memory.
DTC No.

P1572

Trouble diagnosis
name

DTC detecting condition

A)

When the vehicle speed is above 30 km/h

(19 MPH), ON signals from the stop lamp
switch and the ASCD brake switch are sent
to the ECM at the same time.

B)

ASCD brake switch signal is not sent to

ECM for extremely long time while the vehicle is driving.

ASCD brake switch

Possible cause
Harness or connectors
(The stop lamp switch circuit is shorted.)
Harness or connectors
(The ASCD brake switch circuit is shorted.)
Stop lamp switch
ASCD brake switch
Incorrect stop lamp switch installation
Incorrect ASCD brake switch installation
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
NOTE:
Procedure for malfunction B is not described here. It takes extremely long time to complete procedure for malfunction B. By performing procedure for malfunction A, the incident that causes malfunction B can be
detected.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

1.
2.
3.
4.

With CONSULT-III
Start engine (VDC switch OFF).
Select DATA MONITOR mode with CONSULT-III.
Press MAIN switch and make sure that CRUISE lamp lights up.
Drive the vehicle for at least 5 consecutive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.

VHCL SPEED SE

More than 30 km/h (19 mph)

Selector lever

Suitable position

Revision: 2007 June

EC-428

G37 Coupe

P1572 ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

5. Check 1st trip DTC.
With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-429, "Diagnosis Procedure".
NO
>> GO TO 3.

EC

3.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
1. Drive the vehicle for at least 5 consecutive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.

VHCL SPEED SE

More than 30 km/h (19 mph)

Selector lever

Suitable position

Driving location

Depress the brake pedal for more than

five seconds so as not to come off from
the above-mentioned vehicle speed.

2.

Check 1st trip DTC.

With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-429, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734255

1.CHECK OVERALL FUNCTION-I

1.
2.
3.

With CONSULT-III
Turn ignition switch ON.
Select BRAKE SW1 in DATA MONITOR mode with CONSULT-III.
Check BRAKE SW1 indication under the following conditions.

L
Monitor item
BRAKE SW1

1.
2.

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Indication
Slightly depressed

OFF

Fully released

ON

Without CONSULT-III
Turn ignition switch ON.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

M107

126
(ASCD brake switch signal)

Ground

Ground

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Voltage
Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> GO TO 2.
NO-1 >> A/T models: GO TO 3.
NO-2 >> M/T models: GO TO 8.

2.CHECK OVERALL FUNCTION-II

With CONSULT-III
Revision: 2007 June

EC-429

G37 Coupe

P1572 ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Select BRAKE SW2 and check indication under the following conditions.
Monitor item
BRAKE SW2

Condition
Brake pedal

Indication

Slightly depressed

ON

Fully released

OFF

Without CONSULT-III
Check the voltage between ECM harness connector and ground.
ECM

Ground

Connector

Terminal

M107

122
(Stop lamp switch signal)

Ground

Condition

Brake pedal

Slightly depressed

Voltage
Battery voltage

Fully released

Approx. 0V

Is the inspection result normal?

YES >> GO TO 21.
NO
>> GO TO 16.

3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ASCD brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ASCD brake switch harness connector and ground.
ASCD brake switch

Connector

Terminal

E109

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground in harness or connectors.

5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ASCD brake switch harness connector and ECM harness connector.
ASCD brake switch

ECM

Connector

Terminal

Connector

Terminal

E109

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Revision: 2007 June

EC-430

G37 Coupe

P1572 ASCD BRAKE SWITCH

< COMPONENT DIAGNOSIS >
Harness for open or short between ECM and ASCD brake switch

[VQ37VHR]
A

>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK ASCD BRAKE SWITCH

EC

Refer to EC-433, "Component Inspection (ASCD Brake Switch)"

Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace ASCD brake switch.

8.CHECK ASCD BRAKE SWITCH CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ASCD brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ASCD brake switch harness connector and ground.
ASCD brake switch

Connector

Terminal

E109

Ground

Ground

Condition

Brake pedal

Voltage

Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> GO TO 13.
NO
>> GO TO 9.

9.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ASCD clutch switch harness connector.
Turn ignition switch ON.
Check the voltage between ASCD clutch switch harness connector and ground.

J
ASCD clutch switch
Connector

Terminal

E108

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 11.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

M

Check the following.

Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ASCD clutch switch and fuse

>> Repair open circuit or short to ground in harness or connectors.

O

11.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Turn ignition switch OFF.

Check the continuity between ASCD clutch switch harness connector and ASCD brake switch harness
connector.
ASCD clutch switch

ASCD brake switch

Connector

Terminal

Connector

Terminal

E108

E109

3.

Continuity
Existed

Also check harness for short to ground and short to power.

Revision: 2007 June

EC-431

G37 Coupe

P1572 ASCD BRAKE SWITCH

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 12.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

[VQ37VHR]

12.CHECK ASCD CLUTCH SWITCH

Refer to EC-434, "Component Inspection (ASCD Clutch Switch)".
Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace ASCD clutch switch.

13.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ASCD brake switch harness connector and ECM harness connector.
ASCD brake switch

ECM

Connector

Terminal

Connector

Terminal

E109

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 15.
NO
>> GO TO 14.

14.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness for open or short between ECM and ASCD brake switch
>> Repair open circuit or short to ground or short to power in harness or connectors.

15.CHECK ASCD BRAKE SWITCH

Refer to EC-433, "Component Inspection (ASCD Brake Switch)".
Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace ASCD brake switch.

16.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.

Turn ignition switch OFF.

Disconnect stop lamp switch harness connector.
Check the voltage between stop lamp switch harness connector and ground.
Stop lamp switch

Connector

Terminal

E110

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 18.
NO
>> GO TO 17.

17.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 7)
Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
Revision: 2007 June

EC-432

G37 Coupe

P1572 ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

18.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Disconnect ECM harness connector.

Check the continuity between stop lamp switch harness connector and ECM harness connector.
EC
Stop lamp switch

ECM

Connector

Terminal

Connector

Terminal

E110

M107

122

Continuity

Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 20.
NO
>> GO TO 19.

19.DETECT MALFUNCTIONING PART

Check the following.

Fuse block (J/B) connectors E103, M2
Harness for open or short between ECM and stop lamp switch

>> Repair open circuit or short to ground or short to power in harness or connectors.

20.CHECK STOP LAMP SWITCH

Refer to EC-434, "Component Inspection (Stop Lamp Switch)"

Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace stop lamp switch.

21.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

J

>> INSPECTION END

Component Inspection (ASCD Brake Switch)

INFOID:0000000001734256

1.CHECK ASCD BRAKE SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ASCD brake switch harness connector.
Check the continuity between ASCD brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ASCD BRAKE SWITCH-II

1.
2.

Adjust ASCD brake switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between ASCD brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

Revision: 2007 June

EC-433

G37 Coupe

P1572 ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> INSPECTION END
NO
>> Replace ASCD brake switch.

Component Inspection (ASCD Clutch Switch)

INFOID:0000000001734257

1.CHECK ASCD CLUTCH SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ASCD clutch switch harness connector.
Check the continuity between ASCD clutch switch terminals under the following conditions.

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ASCD CLUTCH SWITCH-II

1.
2.

Adjust ASCD clutch switch installation. Refer to CL-5, "Inspection and Adjustment".
Check the continuity between ASCD clutch switch terminals under the following conditions.

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ASCD clutch switch.

Component Inspection (Stop Lamp Switch)

INFOID:0000000001734258

1.CHECK STOP LAMP SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect stop lamp switch harness connector.
Check the continuity between stop lamp switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Not existed
Existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK STOP LAMP SWITCH-II

1.
2.

Adjust stop lamp switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between stop lamp switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Not existed
Existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace stop lamp switch.

Revision: 2007 June

EC-434

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1572 ICC BRAKE SWITCH

Description

INFOID:0000000001734259

When the brake pedal is depressed, ICC brake switch is turned OFF and stop lamp switch is turned ON. ECM EC
detects the state of the brake pedal by this input of two kinds (ON/OFF signal).
Refer to CCS-15, "System Description" for the ICC function.

DTC Logic

INFOID:0000000001734260

NOTE:
If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-356, "DTC Logic".
This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two
consecutive trips, DTC is not stored in ECM memory.

DTC DETECTION LOGIC

F
DTC No.

P1572

Trouble diagnosis
name

DTC detecting condition

A)

ON signals from the stop lamp switch and

the ICC brake switch are sent to ECM at
the same time.

B)

ICC brake switch signal is not sent to ECM

for extremely long time while the vehicle is
driving

ICC brake switch

Possible cause
Harness or connectors
(The stop lamp switch circuit is shorted.)
Harness or connectors
(The ICC brake switch circuit is shorted.)
Stop lamp switch
ICC brake switch
ICC brake hold relay
Incorrect stop lamp switch installation
Incorrect ICC brake switch installation
ECM

DTC CONFIRMATION PROCEDURE

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
NOTE:
Procedure for malfunction B is not described here. It takes extremely long time to complete procedure for malfunction B. By performing procedure for malfunction A, the incident that causes malfunction B can be
detected.
>> GO TO 2.

With CONSULT-III
Start engine (VDC switch OFF).
Select DATA MONITOR mode with CONSULT-III.
Press MAIN switch and make sure that CRUISE lamp lights up.
Drive the vehicle for at least 5 consecutive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.

EC-435

2.PERFORM DTC CONFIRMATION PROCEDURE

Revision: 2007 June

1.PRECONDITIONING

1.
2.
3.
4.

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

VHCL SPEED SE

More than 30 km/h (19 mph)

Selector lever

Suitable position

5.

Check 1st trip DTC.

With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-436, "Diagnosis Procedure".
NO
>> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE

1.

With CONSULT-III
Drive the vehicle for at least 5 consecutive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.

VHCL SPEED SE

More than 30 km/h (19 mph)

Selector lever

Suitable position

Driving location

Depress the brake pedal for more than

five seconds so as not to come off from
the above-mentioned vehicle speed.

2.

Check 1st trip DTC.

With GST
Follow the procedure With CONSULT-III above.
Is 1st trip DTC detected?
YES >> Go to EC-436, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734261

1.CHECK OVERALL FUNCTION-I

1.
2.
3.

With CONSULT-III
Turn ignition switch ON.
Select BRAKE SW1 in DATA MONITOR mode with CONSULT-III.
Check BRAKE SW1 indication under the following conditions.

Monitor item
BRAKE SW1

1.
2.

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Indication
Slightly depressed

OFF

Fully released

ON

Without CONSULT-III
Turn ignition switch ON.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

M107

126
(ICC brake switch signal)

Ground

Ground

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Voltage
Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> GO TO 2.
NO-1 >> A/T models: GO TO 3.
Revision: 2007 June

EC-436

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO-2 >> M/T models: GO TO 8.

2.CHECK OVERALL FUNCTION-II

With CONSULT-III
Select BRAKE SW2 and check indication under the following conditions.
Monitor item
BRAKE SW2

Condition
Brake pedal

EC

Indication

Slightly depressed

ON

Fully released

OFF

Without CONSULT-III
Check the voltage between ECM harness connector and ground.
ECM

Ground

Connector

Terminal

M107

122
(Stop lamp switch signal)

Condition

Ground

Brake pedal

Slightly depressed
Fully released

Voltage
Battery voltage

Approx. 0V

Is the inspection result normal?

YES >> GO TO 22.
NO
>> GO TO 16.

3.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ICC brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ICC brake switch harness connector and ground.
ICC brake switch

Connector

Terminal

E114

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.

Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ICC brake switch and fuse

>> Repair open circuit or short to ground in harness or connectors.

5.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ICC brake switch harness connector and ECM harness connector.

P
ICC brake switch

ECM

Connector

Terminal

Connector

Terminal

E114

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 7.
Revision: 2007 June

EC-437

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> GO TO 6.

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness for open or short between ICC brake switch and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

7.CHECK ICC BRAKE SWITCH

Refer to EC-441, "Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 22.
NO
>> Replace ICC brake switch.

8.CHECK ICC BRAKE SWITCH CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ICC brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ICC brake switch harness connector and ground.
ICC brake switch

Connector

Terminal

E114

Ground

Ground

Condition

Brake pedal

Voltage

Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> GO TO 13.
NO
>> GO TO 9.

9.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ICC clutch switch harness connector.
Turn ignition switch ON.
Check the voltage between ICC clutch switch harness connector and ground.
ICC clutch switch

Connector

Terminal

E113

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 11.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ICC clutch switch and fuse
>> Repair open circuit or short to ground in harness or connectors.

11.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Turn ignition switch OFF.

Check the continuity between ICC clutch switch harness connector and ICC brake switch harness connector.

Revision: 2007 June

EC-438

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ICC clutch switch

ICC brake switch

Connector

Terminal

Connector

Terminal

E113

E114

A
Continuity
Existed

EC

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 12.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

12.CHECK ICC CLUTCH SWITCH

D

Refer to EC-441, "Component Inspection (ICC Clutch Switch)".

Is the inspection result normal?
YES >> GO TO 22.
NO
>> Replace ICC clutch switch.

13.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ICC brake switch harness connector and ECM harness connector.

G
ICC brake switch

ECM

Connector

Terminal

Connector

Terminal

E114

M107

126

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 15.
NO
>> GO TO 14.

14.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors E106, M6
Harness for open or short between ICC brake switch and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

15.CHECK ICC BRAKE SWITCH

Refer to EC-441, "Component Inspection (ICC Brake Switch)".

Is the inspection result normal?
YES >> GO TO 22.
NO
>> Replace ICC brake switch.

16.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect stop lamp switch harness connector.
Disconnect ICC brake hold relay harness connector.
Check the voltage between stop lamp switch harness connector and ground.
Stop lamp switch

Connector

Terminal

E110

5.

P
Ground

Voltage

Ground

Battery voltage

Check the voltage between ICC brake hold relay harness connector and ground.

Revision: 2007 June

EC-439

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ICC brake hold relay
Connector

Terminal

E51

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 18.
NO
>> GO TO 17.

17.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 7)
Harness for open or short between battery and stop lamp switch
Harness for open or short between battery and ICC brake hold relay
>> Repair open circuit or short to ground in harness or connectors.

18.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Disconnect ECM harness connector.

Check the continuity between stop lamp switch harness connector and ECM harness connector.
Stop lamp switch

ECM

Connector

Terminal

Connector

Terminal

E110

M107

122

3.

Continuity
Existed

Check the continuity between ICC brake hold relay harness connector and ECM harness connector.
ICC brake hold relay

ECM

Connector

Terminal

Connector

Terminal

E51

M107

122

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 20.
NO
>> GO TO 19.

19.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103, M2
Harness for open or short between ECM and stop lamp switch
Harness for open or short between ECM and ICC brake hold relay
>> Repair open circuit or short to ground or short to power in harness or connectors.

20.CHECK STOP LAMP SWITCH

Refer to EC-442, "Component Inspection (Stop Lamp Switch)".
Is the inspection result normal?
YES >> GO TO 21.
NO
>> Replace stop lamp switch.

21.CHECK ICC BRAKE HOLD RELAY

Refer to EC-442, "Component Inspection (ICC Brake Hold Relay)".
Is the inspection result normal?
YES >> GO TO 22.
NO
>> Replace ICC brake hold relay.
Revision: 2007 June

EC-440

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

22.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

EC

Component Inspection (ICC Brake Switch)

INFOID:0000000001734262

1.CHECK ICC BRAKE SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ICC brake switch harness connector.
Check the continuity between ICC brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Fully released

Brake pedal

Slightly depressed

Continuity

Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ICC BRAKE SWITCH-II

1.
2.

Adjust ICC brake switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between ICC brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Fully released

Brake pedal

Slightly depressed

Continuity
Existed

Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ICC brake switch.

Component Inspection (ICC Clutch Switch)

INFOID:0000000001734263

1.CHECK ICC CLUTCH SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ICC clutch switch harness connector.
Check the continuity between ICC clutch switch terminals under the following conditions.

M
Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed

Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ICC CLUTCH SWITCH-II

1.
2.

Adjust ICC clutch switch installation. Refer to CL-5, "Inspection and Adjustment".
Check the continuity between ICC clutch switch terminals under the following conditions.

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

Revision: 2007 June

EC-441

G37 Coupe

P1572 ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> INSPECTION END
NO
>> Replace ICC clutch switch.

Component Inspection (Stop Lamp Switch)

INFOID:0000000001911037

1.CHECK STOP LAMP SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect stop lamp switch harness connector.
Check the continuity between stop lamp switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Not existed
Existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK STOP LAMP SWITCH-II

1.
2.

Adjust stop lamp switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between stop lamp switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Not existed
Existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace stop lamp switch.

Component Inspection (ICC Brake Hold Relay)

INFOID:0000000001734265

1.CHECK ICC BRAKE HOLD RELAY

1.
2.
3.

Turn ignition switch OFF.

Remove ICC brake hold relay.
Check the continuity between ICC brake hold relay terminals
under the following conditions.

Terminals
3 and 5

Condition

Continuity

12V direct current supply between terminals 1 and 2

Existed

No current supply

Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ICC brake hold relay
JMBIA0848ZZ

Revision: 2007 June

EC-442

G37 Coupe

P1574 ASCD VEHICLE SPEED SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1574 ASCD VEHICLE SPEED SENSOR

Description

INFOID:0000000001734266

The ECM receives two vehicle speed sensor signals via CAN communication line. One is sent from unified EC
meter and A/C amp., and the other is from TCM (Transmission control module). The ECM uses these signals
for ASCD control. Refer to EC-62, "System Description" for ASCD functions.

DTC Logic

INFOID:0000000001734267

NOTE:
If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-146, "DTC Logic".
If DTC P1574 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500. Refer
to EC-337, "DTC Logic".
If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-356, "DTC Logic".

DTC DETECTION LOGIC

DTC No.

P1574

Trouble diagnosis
name

ASCD vehicle speed

sensor

DTC detecting condition

ECM detects a difference between two vehicle

speed signals is out of the specified range.

Possible cause
Harness or connectors
(The CAN communication line is open or
shorted.)
Unified meter and A/C amp.
ABS actuator and electric unit (control unit)
Wheel sensor
TCM
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.

Start engine (VDC switch OFF).

Drive the vehicle at more than 40 km/h (25 MPH).
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-443, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734268

1.CHECK DTC WITH TCM

Check DTC with TCM. Refer to TM-111, "Diagnosis Description".
Revision: 2007 June

EC-443

G37 Coupe

P1574 ASCD VEHICLE SPEED SENSOR

< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Perform trouble shooting relevant to DTC indicated.

[VQ37VHR]

2.CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Refer to BRC-26, "CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".
>> INSPECTION END

Revision: 2007 June

EC-444

G37 Coupe

P1574 ICC VEHICLE SPEED SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1574 ICC VEHICLE SPEED SENSOR

Description

INFOID:0000000001734269

The ECM receives two vehicle speed signals via CAN communication line. One is sent from unified meter and EC
A/C amp., and the other is from TCM (Transmission control module). The ECM uses these signals for ICC
control. Refer to CCS-15, "System Description" for ICC functions.

DTC Logic

INFOID:0000000001734270

NOTE:
If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-146, "DTC Logic".
If DTC P1574 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500. Refer
to EC-337, "DTC Logic".
If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-356, "DTC Logic".

DTC DETECTION LOGIC

DTC No.

P1574

Trouble diagnosis
name

ICC vehicle speed

sensor

DTC detecting condition

ECM detects a difference between two vehicle

speed signals is out of the specified range.

Possible cause
Harness or connectors
(The CAN communication line is open or
shorted.)
Unified meter and A/C amp.
ABS actuator and electric unit (control unit)
Wheel sensor
TCM
ECM

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.

Start engine (VDC switch OFF).

Drive the vehicle at more than 40 km/h (25 MPH).
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-445, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734271

1.CHECK DTC WITH TCM

Check DTC with TCM. Refer to TM-111, "Diagnosis Description".
Is the inspection result normal?
YES >> GO TO 2.
Revision: 2007 June

EC-445

G37 Coupe

P1574 ICC VEHICLE SPEED SENSOR

< COMPONENT DIAGNOSIS >
NO
>> Perform trouble shooting relevant to DTC indicated.

[VQ37VHR]

2.CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Refer to BRC-26, "CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Check combination meter function.
Refer to MWI-37, "CONSULT-III Function (METER/M&A)".
>> INSPECTION END

Revision: 2007 June

EC-446

G37 Coupe

P1606 VVEL CONTROL MODULE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1606 VVEL CONTROL MODULE

Description

INFOID:0000000001736777

The VVEL control module consists of a microcomputer and connectors for signal input and output and for power supply. The VVEL control module controls VVEL system.

EC

JMBIA0879ZZ

DTC Logic

INFOID:0000000001736778

DTC DETECTION LOGIC

DTC No.

P1606

Trouble diagnosis name

VVEL control module

DTC detecting condition

VVEL control module calculation
function is malfunctioning.
VVEL EEP-ROM system is malfunctioning.

Possible cause

G
VVEL control module

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.
1. Turn ignition switch ON and wait at least 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-447, "Diagnosis Procedure".
NO
>> INSPECTION END

N
INFOID:0000000001736779

1.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-447, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
1.
2.
3.
4.

Revision: 2007 June

2.PERFORM DTC CONFIRMATION PROCEDURE

Diagnosis Procedure

EC-447

G37 Coupe

P1606 VVEL CONTROL MODULE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

See EC-447, "DTC Logic".
Is the DTC P1606 displayed again?
YES >> GO TO 2.
NO
>> INSPECTION END

2.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> INSPECTION END

Revision: 2007 June

EC-448

G37 Coupe

P1607 VVEL CONTROL MODULE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1607 VVEL CONTROL MODULE

Description

A
INFOID:0000000001910908

The VVEL control module consists of a microcomputer and connectors for signal input and output and for power supply. The VVEL control module controls VVEL system.

EC

JMBIA0879ZZ

DTC Logic

INFOID:0000000001736781

DTC DETECTION LOGIC

DTC No.
P1607

Trouble diagnosis name

VVEL control module circuit

DTC detecting condition

The internal circuit of the VVEL control module is malfunctioning.

Possible cause

G
VVEL control module

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

L

1. Start engine and let it idle for at least 1 second.

2. Check DTC.
Is DTC detected?
YES >> Go to EC-449, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736782

1.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III
Turn ignition switch ON.
Select SELF-DIAG RESULTS mode with CONSULT-III.
Touch ERASE.
Perform DTC Confirmation Procedure.
See EC-449, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-449, "DTC Logic".

1.
2.
3.
4.

Revision: 2007 June

EC-449

G37 Coupe

P1607 VVEL CONTROL MODULE

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the DTC P1607 displayed again?
YES >> GO TO 2.
NO
>> INSPECTION END

2.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> INSPECTION END

Revision: 2007 June

EC-450

G37 Coupe

P1608 VVEL SENSOR POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1608 VVEL SENSOR POWER SUPPLY

DTC Logic

INFOID:0000000001736783

DTC DETECTION LOGIC

DTC No.

P1608

EC

Trouble diagnosis name

DTC detecting condition

Possible cause

VVEL sensor power supply circuit

VVEL control module detects a voltage

of power source for sensor is excessively
low or high.

Harness or connectors
(VVEL control shaft position sensor
power supply circuit is open or shorted.)
VVEL control shaft position sensor
VVEL control module

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-451, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001736784

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.VVEL CONTROL SHAFT POSITION SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect VVEL control shaft position sensor harness connector.

Turn ignition switch ON.
Check the voltage between VVEL control shaft position sensor harness connector and ground.

VVEL control shaft position sensor

Bank

Connector

F46

F47

Terminal

Ground

Voltage

3
6
3

P
Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 3.
Revision: 2007 June

EC-451

G37 Coupe

P1608 VVEL SENSOR POWER SUPPLY

[VQ37VHR]

< COMPONENT DIAGNOSIS >

3.CHECK VVEL CONTROL SHAFT POSITION SENSOR POWER SUPPLY CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Disconnect VVEL control module harness connector.
3. Check the continuity between VVEL control shaft position sensor harness connector and VVEL control
module harness connector.
VVEL control shaft position sensor
Bank

Connector

F46

Terminal

F47

VVEL control module

Connector

Terminal

3
6
3

Continuity

9
22

E15

Existed

20

4. Also check harness for short to ground and power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F1, E3
Harness for open or short between VVEL control shaft position sensor and VVEL control module
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair or replace.

6.REPLACE VVEL CONTROL MODULE

1.
2.

Replace VVEL control module.

Go to EC-17, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL MODULE) : Special Repair Requirement".
>> INSPECTION END

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 8.
NO
>> Repair or replace.

8.REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.
2.

Replace VVEL actuator sub assembly.

Go to EC-452, "Special Repair Requirement".
>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910907

1.PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

Revision: 2007 June

EC-452

G37 Coupe

P1608 VVEL SENSOR POWER SUPPLY

[VQ37VHR]
< COMPONENT DIAGNOSIS >
Refer to EC-21, "VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Special Repair Requirement".

>> GO TO 2.

2.PERFORM IDLE AIR VOLUME LEARNING

EC

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".

C

>> END
D

Revision: 2007 June

EC-453

G37 Coupe

P1715 INPUT SPEED SENSOR (TURBINE REVOLUTION SENSOR)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1715 INPUT SPEED SENSOR (TURBINE REVOLUTION SENSOR)

Description

INFOID:0000000001734272

ECM receives turbine revolution sensor signal from TCM through CAN communication line. ECM uses this
signal for engine control.

DTC Logic

INFOID:0000000001734273

DTC DETECTION LOGIC

NOTE:
If DTC P1715 is displayed with DTC U1000, U1001 first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-146, "DTC Logic".
If DTC P1715 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-147, "DTC Logic".
If DTC P1715 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-356, "DTC Logic".
If DTC P1715 is displayed with DTC P0335, first perform the trouble diagnosis for DTC P0335. Refer
to EC-264, "DTC Logic".
If DTC P1715 is displayed with DTC P0340, first perform the trouble diagnosis for DTC P0340. Refer
to EC-268, "DTC Logic".
DTC No.

P1715

Trouble diagnosis name

Input speed sensor

(Turbine revolution sensor)
(TCM output)

DTC detecting condition

Possible cause

Turbine revolution sensor signal is different from the theoretical value calculated
by ECM from revolution sensor signal and
engine rpm signal.

Harness or connectors
(The CAN communication line is open or shorted)
Harness or connectors
(Turbine revolution sensor circuit is open or
shorted)
TCM

Diagnosis Procedure

INFOID:0000000001734274

1.CHECK DTC WITH TCM

Check DTC with TCM. Refer to TM-111, "Diagnosis Description".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Perform trouble shooting relevant to DTC indicated.

2.REPLACE TCM
Replace TCM.
>> INSPECTION END

Revision: 2007 June

EC-454

G37 Coupe

P1805 BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P1805 BRAKE SWITCH

Description

INFOID:0000000001734275

Brake switch signal is applied to the ECM through the stop lamp switch when the brake pedal is depressed. EC
This signal is used mainly to decrease the engine speed when the vehicle is driving.

DTC Logic

INFOID:0000000001734276

DTC DETECTION LOGIC

DTC No.

P1805

DTC detecting condition

Possible cause

A brake switch signal is not sent to ECM for extremely long time while the vehicle is driving.

Harness or connectors
(Stop lamp switch circuit is open or shorted.)
Stop lamp switch

Trouble diagnosis name

Brake switch

DTC CONFIRMATION PROCEDURE

1.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-455, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734277

1.CHECK STOP LAMP SWITCH CIRCUIT

1.
2.

Turn ignition switch OFF.

Check the stop lamp when depressing and releasing the brake pedal.
Brake pedal

Stop lamp

Fully released

Not illuminated

Slightly depressed

Illuminated

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 2.

2.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1.
2.

Disconnect stop lamp switch harness connector.

Check the voltage between stop lamp switch harness connector and ground.
Stop lamp switch

Connector

Terminal

E110

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 7)
Revision: 2007 June

EC-455

G37 Coupe

P1805 BRAKE SWITCH

< COMPONENT DIAGNOSIS >
Harness for open or short between stop lamp switch and battery

[VQ37VHR]

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Disconnect stop lamp switch harness connector.

Disconnect ECM harness connector.
Check the continuity between stop lamp switch harness connector and ECM harness connector.
Stop lamp switch

ECM

Connector

Terminal

Connector

Terminal

E110

M107

122

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103, M2
Harness for open or short between ECM and stop lamp switch
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK STOP LAMP SWITCH

Refer to EC-456, "Component Inspection (Stop Lamp Switch)".
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Replace stop lamp switch.

7.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection (Stop Lamp Switch)

INFOID:0000000001911038

1.CHECK STOP LAMP SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect stop lamp switch harness connector.
Check the continuity between stop lamp switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Not existed
Existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK STOP LAMP SWITCH-II

1.
2.

Adjust stop lamp switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between stop lamp switch terminals under the following conditions.

Revision: 2007 June

EC-456

G37 Coupe

P1805 BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Not existed
Existed

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace stop lamp switch.

Revision: 2007 June

EC-457

G37 Coupe

P2122, P2123 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P2122, P2123 APP SENSOR

Description

INFOID:0000000001734279

The accelerator pedal position sensor is installed on the upper end

of the accelerator pedal assembly. The sensor detects the accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
PBIB1741E
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine operation such as fuel cut.

DTC Logic

INFOID:0000000001734280

DTC DETECTION LOGIC

NOTE:
If DTC P2122 or P2123 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-358, "DTC Logic".
DTC No.

Trouble diagnosis name

DTC detecting condition

P2122

Accelerator pedal position sensor 1 circuit low

input

An excessively low voltage from the APP sensor 1 is sent to ECM.

P2123

Accelerator pedal position sensor 1 circuit high

input

An excessively high voltage from the APP sensor 1 is sent to ECM.

Possible cause
Harness or connectors
(APP sensor 1 circuit is open or shorted.)
Accelerator pedal position sensor
(APP sensor 1)

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-458, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734281

1.CHECK GROUND CONNECTION

1.
2.

Turn ignition switch OFF.

Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".

Revision: 2007 June

EC-458

G37 Coupe

P2122, P2123 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

EC

Disconnect accelerator pedal position (APP) sensor harness connector.

Turn ignition switch ON.
Check the voltage between APP sensor harness connector and ground.
APP sensor

Connector

Terminal

E112

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.

Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK APP SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between APP sensor harness connector and ECM harness connector.
APP sensor

ECM

Connector

Terminal

Connector

Terminal

E112

M107

100

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor

>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between APP sensor harness connector and ECM harness connector.
APP sensor

ECM

Connector

Terminal

Connector

Terminal

E112

M107

97

Continuity

Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> GO TO 7.
Revision: 2007 June

EC-459

G37 Coupe

P2122, P2123 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

7.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

8.CHECK APP SENSOR

Refer to EC-460, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 9.

9.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-460, "Special Repair Requirement".
>> INSPECTION END

10.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection

INFOID:0000000001734282

1.CHECK ACCELERATOR PEDAL POSITION SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Turn ignition switch ON.
Check the voltage ECM harness connector and ground.
ECM

Connector

Terminal

Ground

Condition
Fully released

97 (APP sensor 1)
M107

Ground

Accelerator pedal

98 (APP sensor 2)

Fully depressed
Fully released
Fully depressed

Voltage
0.45 - 1.00V
4.4 - 4.8V
0.22 - 0.50V
2.1 - 2.5V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-460, "Special Repair Requirement".
>> INSPECTION END

Special Repair Requirement

INFOID:0000000001734283

1.PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

Refer to EC-18, "ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement".

Revision: 2007 June

EC-460

G37 Coupe

P2122, P2123 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> GO TO 2.

2.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
EC

>> GO TO 3.

3.PERFORM IDLE AIR VOLUME LEARNING

C

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".

>> END

Revision: 2007 June

EC-461

G37 Coupe

P2127, P2128 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P2127, P2128 APP SENSOR

Description

INFOID:0000000001911130

The accelerator pedal position sensor is installed on the upper end

of the accelerator pedal assembly. The sensor detects the accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
PBIB1741E
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine operation such as fuel cut.

DTC Logic

INFOID:0000000001734285

DTC DETECTION LOGIC

DTC No.

Trouble diagnosis name

DTC detecting condition

P2127

Accelerator pedal position sensor 2 circuit low

input

An excessively low voltage from the APP sensor 2 is sent to ECM.

P2128

Accelerator pedal position sensor 2 circuit high

input

An excessively high voltage from the APP sensor 2 is sent to ECM.

Possible cause
Harness or connectors
(APP sensor 2 circuit is open or shorted.)
[CKP sensor (POS) circuit is shorted.]
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
Accelerator pedal position sensor (APP
sensor 2)
(Brake booster pressure sensor circuit is
shorted)
Crankshaft position sensor (POS)
EVAP control system pressure sensor
Refrigerant pressure sensor
Brake booster pressure sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-463, "Diagnosis Procedure".
NO
>> INSPECTION END

Revision: 2007 June

EC-462

G37 Coupe

P2127, P2128 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Diagnosis Procedure

INFOID:0000000001734286

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

EC

2.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-I

1.
2.
3.

Disconnect accelerator pedal position (APP) sensor harness connector.

Turn ignition switch ON.
Check the voltage between APP sensor harness connector and ground.

E
APP sensor
Connector

Terminal

E112

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 3.

3.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between APP sensor harness connector and ECM harness connector.

I
APP sensor

ECM

Connector

Terminal

Connector

Terminal

E112

M107

103

Continuity

Existed

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

L

Check the following.

Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor

>> Repair open circuit.

5.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-III

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector
F101

M107

Sensor

Terminal

Name

O
Connector

Terminal

E48

F2

45

Brake booster pressure sensor

46

CKP sensor (POS)

103

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

Is the inspection result normal?

YES >> GO TO 6.
Revision: 2007 June

EC-463

G37 Coupe

P2127, P2128 APP SENSOR

< COMPONENT DIAGNOSIS >
NO
>> Repair short to ground or short to power in harness or connectors.

[VQ37VHR]

6.CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-267, "Component Inspection".)
Brake booster pressure sensor (Refer to EC-352, "Component Inspection".)
EVAP control system pressure sensor (Refer to EC-306, "Component Inspection".)
Refrigerant pressure sensor (Refer to HAC-85, "Diagnosis Procedure".)
Is the inspection result normal?
YES >> GO TO 13.
NO
>> Replace malfunctioning component.

7.CHECK APP SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between APP sensor harness connector and ECM harness connector.
APP sensor

ECM

Connector

Terminal

Connector

Terminal

E112

M107

104

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK APP SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between APP sensor harness connector and ECM harness connector.
APP sensor

ECM

Connector

Terminal

Connector

Terminal

E112

M107

98

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 11.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

11.CHECK APP SENSOR

Refer to EC-465, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.
Revision: 2007 June

EC-464

G37 Coupe

P2127, P2128 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

12.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-465, "Special Repair Requirement".
EC

>> INSPECTION END

13.CHECK INTERMITTENT INCIDENT

C

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001911132

1.CHECK ACCELERATOR PEDAL POSITION SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Turn ignition switch ON.
Check the voltage ECM harness connector and ground.
ECM

Connector

Terminal

Ground

Condition
Fully released

97 (APP sensor 1)
M107

Ground

Accelerator pedal

98 (APP sensor 2)

Fully depressed
Fully released
Fully depressed

Voltage
0.45 - 1.00V

4.4 - 4.8V
0.22 - 0.50V
2.1 - 2.5V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-470, "Special Repair Requirement".

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001911133

1.PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

Refer to EC-18, "ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement".
N

>> GO TO 2.

2.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
>> GO TO 3.

3.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
>> END

Revision: 2007 June

EC-465

G37 Coupe

P2138 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P2138 APP SENSOR

Description

INFOID:0000000001911131

The accelerator pedal position sensor is installed on the upper end

of the accelerator pedal assembly. The sensor detects the accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
PBIB1741E
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine operation such as fuel cut.

DTC Logic

INFOID:0000000001734290

DTC DETECTION LOGIC

NOTE:
If DTC P2138 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to
EC-358, "DTC Logic".
DTC No.

P2138

Trouble diagnosis name

Accelerator pedal position sensor circuit range/

performance

DTC detecting condition

Possible cause

Rationally incorrect voltage is sent to ECM

compared with the signals from APP sensor 1
and APP sensor 2.

Harness or connectors
(APP sensor 2 circuit is open or shorted.)
[CKP sensor (POS) circuit is shorted.]
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
Accelerator pedal position sensor (APP
sensor 2)
(Brake booster pressure sensor circuit is
shorted)
Crankshaft position sensor (POS)
EVAP control system pressure sensor
Brake booster pressure sensor
Refrigerant pressure sensor

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
Revision: 2007 June

EC-466

G37 Coupe

P2138 APP SENSOR

< COMPONENT DIAGNOSIS >
YES >> Go to EC-467, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

[VQ37VHR]
A
INFOID:0000000001734291

1.CHECK GROUND CONNECTION

EC

1. Turn ignition switch OFF.

2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect accelerator pedal position (APP) sensor harness connector.

Turn ignition switch ON.
Check the voltage between APP sensor harness connector and ground.
APP sensor

Connector

Terminal

E112

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-I

1.
2.

Turn ignition switch ON.

Check the voltage between APP sensor harness connector and ground.
APP sensor

Connector

Terminal

E112

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 9.
NO
>> GO TO 5.

5.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between APP sensor harness connector and ECM harness connector.
APP sensor

ECM

Connector

Terminal

Connector

Terminal

E112

M107

103

Continuity
Existed

Is the inspection result normal?

YES >> GO TO 7.
NO
>> GO TO 6.

Revision: 2007 June

EC-467

G37 Coupe

P2138 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

6.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit.

7.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-III

Check harness for short to power and short to ground, between the following terminals.
ECM
Connector
F101

M107

Sensor

Terminal

Name

Connector

Terminal

E48

F2

APP sensor

E112

107

EVAP control system pressure sensor

B30

111

Refrigerant pressure sensor

E77

45

Brake booster pressure sensor

46

CKP sensor (POS)

103

Is the inspection result normal?

YES >> GO TO 8.
NO
>> Repair short to ground or short to power in harness or connectors.

8.CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-267, "Component Inspection".)
Brake booster pressure sensor (Refer to EC-352, "Component Inspection".)
EVAP control system pressure sensor (Refer to EC-306, "Component Inspection".)
Refrigerant pressure sensor (Refer to HAC-85, "Diagnosis Procedure".)
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace malfunctioning component.

9.CHECK APP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between APP sensor harness connector and ECM harness connector.
APP sensor

Connector
E112

ECM

Terminal
4
2

Connector
M107

Terminal
100
104

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 11.
NO
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

11.CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
Revision: 2007 June

EC-468

G37 Coupe

P2138 APP SENSOR

[VQ37VHR]
< COMPONENT DIAGNOSIS >
1. Check the continuity between APP sensor harness connector and ECM harness connector.
A
APP sensor
Connector

ECM

Terminal

Connector

E112

Terminal

Continuity

97

M107

98

EC
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 13.
NO
>> GO TO 12.

12.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and accelerator pedal position sensor

>> Repair open circuit or short to ground or short to power in harness or connectors.

13.CHECK APP SENSOR

G

Refer to EC-469, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 15.
NO
>> GO TO 14.

14.REPLACE ACCELERATOR PEDAL ASSEMBLY

1.
2.

Replace accelerator pedal assembly.

Go to EC-470, "Special Repair Requirement".

>> INSPECTION END

15.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection

INFOID:0000000001911134

1.CHECK ACCELERATOR PEDAL POSITION SENSOR

1.
2.
3.
4.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Turn ignition switch ON.
Check the voltage ECM harness connector and ground.
ECM

Connector

Terminal

Ground

Condition
Fully released

97 (APP sensor 1)
M107

Ground

Accelerator pedal

98 (APP sensor 2)

Fully depressed
Fully released
Fully depressed

Voltage

0.45 - 1.00V
4.4 - 4.8V

0.22 - 0.50V
2.1 - 2.5V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.REPLACE ACCELERATOR PEDAL ASSEMBLY

Revision: 2007 June

EC-469

G37 Coupe

P2138 APP SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

1. Replace accelerator pedal assembly.
2. Go to EC-470, "Special Repair Requirement".
>> INSPECTION END

Special Repair Requirement

INFOID:0000000001911135

1.PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

Refer to EC-18, "ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Requirement".
>> GO TO 2.

2.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
>> GO TO 3.

3.PERFORM IDLE AIR VOLUME LEARNING

Refer to EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
>> END

Revision: 2007 June

EC-470

G37 Coupe

P2A00, P2A03 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

P2A00, P2A03 A/F SENSOR 1

Description

INFOID:0000000001911129

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sensor. The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocarbon density in rich.

EC

JMBIA0112GB

Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800C
(1,472F).

H
PBIB3354E

DTC Logic

INFOID:0000000001734295

DTC DETECTION LOGIC

To judge the malfunction, the A/F signal computed by ECM from the A/F sensor 1 signal is monitored not to be
shifted to LEAN side or RICH side.
DTC No.

Trouble diagnosis name

DTC detecting condition

P2A00

Air fuel ratio (A/F) sensor 1

(bank 1) circuit range/performance

P2A03

Air fuel ratio (A/F) sensor 1

(bank 2) circuit range/performance

The output voltage computed by ECM from the

A/F sensor 1 signal is shifted to the lean side for
a specified period.
The A/F signal computed by ECM from the A/F
sensor 1 signal is shifted to the rich side for a
specified period.

Possible Cause

A/F sensor 1
A/F sensor 1 heater
Fuel pressure
Fuel injector
Intake air leaks

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1.
2.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
Turn ignition switch OFF and wait at least 10 seconds.

Revision: 2007 June

EC-471

G37 Coupe

P2A00, P2A03 A/F SENSOR 1

[VQ37VHR]
< COMPONENT DIAGNOSIS >
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
6. Let engine idle for 1 minute.
7. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-472, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734296

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.RETIGHTEN A/F SENSOR 1

1.

Loosen and retighten the A/F sensor 1. Refer to EM-33, "Removal and Installation".
>> GO TO 3.

3.CHECK FOR INTAKE AIR LEAK

1. Start engine and run it at idle.
2. Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES >> Repair or replace.
NO
>> GO TO 4.

4.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1.

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-233, "Diagnosis
Procedure" or EC-237, "Diagnosis Procedure".
NO
>> GO TO 5.

5.CHECK HARNESS CONNECTOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect A/F sensor 1 harness connector.
Check harness connector for water.
Water should not exit.

Is the inspection result normal?

YES >> GO TO 6.
NO
>> Repair or replace harness connector.

6.CHECK A/F SENSOR 1 POWER SUPPLY CIRCUIT

1.
2.

Turn ignition switch ON.

Check the voltage between A/F sensor 1 harness connector and ground.

Revision: 2007 June

EC-472

G37 Coupe

P2A00, P2A03 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

DTC

A/F sensor 1
Bank

Connector

Terminal

P2A00

F3

P2A03

F20

Ground

Voltage

Ground

Battery voltage

EC

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 7.

7.DETECT MALFUNCTIONING PART

D

Check the following.

Harness connectors E3, F1
IPDM E/R harness connector E7
15A fuse (No. 46)
Harness for open or short between A/F sensor 1 and fuse

>> Repair or replace harness or connectors.

8.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

H
DTC

P2A00

P2A03

4.

A/F sensor 1
Bank

Connector

F3

F20

ECM
Terminal

Connector

Terminal

1
2
1

Continuity

57
61

F102

65

Existed

66

Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.
K
DTC

P2A00

P2A03

A/F sensor 1
Bank

Connector

F3

F20

ECM
Terminal

Connector

1
2
1

Terminal

Ground

Continuity

57
F102

61
65

Ground

Not existed

66

5. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK A/F SENSOR 1 HEATER

Refer to EC-157, "Component Inspection".

Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 11.

10.CHECK INTERMITTENT INCIDENT

Perform GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 11.
Revision: 2007 June

EC-473

G37 Coupe

P2A00, P2A03 A/F SENSOR 1

[VQ37VHR]

< COMPONENT DIAGNOSIS >

NO
>> Repair or replace.

11.REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Do you have CONSULT-III?
YES >> GO TO 12.
NO
>> GO TO 13.

12.CONFIRM A/F ADJUSTMENT DATA

With CONSULT-III
1. Turn ignition switch ON.
2. Select A/F ADJ-B1 and A/F ADJ-B2 in DATA MONITOR mode with CONSULT-III.
3. Make sure that 0.000 is displayed on CONSULT-III screen.
Is 0.000 displayed?
YES >> INSPECTION END
NO
>> GO TO 13.

13.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

Clear the mixture ratio self-learning value. Refer to EC-22, "MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement".
Do you have CONSULT-III?
YES >> GO TO 14.
NO
>> INSPECTION END

14.CONFIRM A/F ADJUSTMENT DATA

1.
2.
3.

With CONSULT-III
Turn ignition switch ON.
Select A/F ADJ-B1 and A/F ADJ-B2 in DATA MONITOR mode with CONSULT-III.
Make sure that 0.000 is displayed on CONSULT-III screen.
>> INSPECTION END

Revision: 2007 June

EC-474

G37 Coupe

ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ASCD BRAKE SWITCH

Description

INFOID:0000000001911042

When the brake pedal is depressed, ASCD brake switch is turned OFF and stop lamp switch is turned ON. EC
ECM detects the state of the brake pedal by this input of two kinds (ON/OFF signal).
Refer to EC-62, "System Description" for the ASCD function.

Component Function Check

INFOID:0000000001734298

1.CHECK ASCD BRAKE SWITCH FUNCTION

D

With CONSULT-III
1. Turn ignition switch ON.
2. Select BRAKE SW1 in DATA MONITOR mode with CONSULT-III.
3. Check BRAKE SW1 indication under the following conditions.
Monitor item
BRAKE SW1

1.
2.

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Indication
Slightly depressed

OFF

Fully released

ON

Without CONSULT-III
Turn ignition switch ON.
Check the voltage between ECM harness connector and ground.

H
ECM

Ground

Connector

Terminal

M107

126
(ASCD brake switch signal)

Ground

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Voltage
Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-475, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734299

1.INSPECTION START
L

Check which type of transmission the vehicle is equipped with.

Which type of transmission?
A/T
>> GO TO 2.
M/T
>> GO TO 7.

2.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ASCD brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ASCD brake switch harness connector and ground.

O
ASCD brake switch
Connector

Terminal

E109

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Check the following.
Revision: 2007 June

EC-475

G37 Coupe

ASCD BRAKE SWITCH

< COMPONENT DIAGNOSIS >
Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ASCD brake switch and fuse

[VQ37VHR]

>> Repair open circuit or short to ground in harness or connectors.

4.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ASCD brake switch harness connector and ECM harness connector.
ASCD brake switch

ECM

Connector

Terminal

Connector

Terminal

E109

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness for open or short between ECM and ASCD brake switch
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK ASCD BRAKE SWITCH

Refer to EC-478, "Component Inspection (ASCD Brake Switch)"
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace ASCD brake switch.

7.CHECK ASCD BRAKE SWITCH CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ASCD brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ASCD brake switch harness connector and ground.
ASCD brake switch

Connector

Terminal

E109

Ground

Ground

Condition

Brake pedal

Voltage

Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> GO TO 12.
NO
>> GO TO 8.

8.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ASCD clutch switch harness connector.
Turn ignition switch ON.
Check the voltage between ASCD clutch switch harness connector and ground.

Revision: 2007 June

EC-476

G37 Coupe

ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ASCD clutch switch
Connector

Terminal

E108

A
Ground

Voltage

Ground

Battery voltage

EC

Is the inspection result normal?

YES >> GO TO 10.
NO
>> GO TO 9.

9.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ASCD clutch switch and fuse

>> Repair open circuit or short to ground in harness or connectors.

10.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Turn ignition switch OFF.

Check the continuity between ASCD clutch switch harness connector and ASCD brake switch harness
connector.
ASCD clutch switch

ASCD brake switch

Connector

Terminal

Connector

Terminal

E108

E109

Continuity

H
Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 11.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

11.CHECK ASCD CLUTCH SWITCH

Refer to EC-478, "Component Inspection (ASCD Clutch Switch)".

Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace ASCD clutch switch.

12.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ASCD brake switch harness connector and ECM harness connector.
ASCD brake switch

ECM

Connector

Terminal

Connector

Terminal

E109

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 13.

13.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness for open or short between ECM and ASCD brake switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
Revision: 2007 June

EC-477

G37 Coupe

ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

14.CHECK ASCD BRAKE SWITCH

Refer to EC-478, "Component Inspection (ASCD Brake Switch)".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace ASCD brake switch.

15.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection (ASCD Brake Switch)

INFOID:0000000001911043

1.CHECK ASCD BRAKE SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ASCD brake switch harness connector.
Check the continuity between ASCD brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ASCD BRAKE SWITCH-II

1.
2.

Adjust ASCD brake switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between ASCD brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Brake pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ASCD brake switch.

Component Inspection (ASCD Clutch Switch)

INFOID:0000000001911044

1.CHECK ASCD CLUTCH SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ASCD clutch switch harness connector.
Check the continuity between ASCD clutch switch terminals under the following conditions.

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ASCD CLUTCH SWITCH-II

1.
2.

Adjust ASCD clutch switch installation. Refer to CL-5, "Inspection and Adjustment".
Check the continuity between ASCD clutch switch terminals under the following conditions.

Revision: 2007 June

EC-478

G37 Coupe

ASCD BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ASCD clutch switch.

Revision: 2007 June

EC-479

G37 Coupe

ASCD INDICATOR
[VQ37VHR]

< COMPONENT DIAGNOSIS >

ASCD INDICATOR
Description

INFOID:0000000001734302

ASCD indicator lamp illuminates to indicate ASCD operation status. Lamp has two indicators, CRUISE and
SET, and is integrated in combination meter.
CRUISE lamp illuminates when MAIN switch on ASCD steering switch is turned ON to indicated that ASCD
system is ready for operation.
SET lamp illuminates when following conditions are met.
CRUISE lamp is illuminated.
SET/COAST switch on ASCD steering switch is turned ON while vehicle speed is within the range of ASCD
setting.
SET lamp remains lit during ASCD control.
Refer to EC-62, "System Description" for the ASCD function.

Component Function Check

INFOID:0000000001734303

1.CHECK ASCD INDICATOR FUNCTION

Check ASCD indicator under the following conditions.
ASCD INDICATOR

CONDITION
MAIN switch: Pressed at the
1st time
at the 2nd time

CRUISE LAMP

Ignition switch: ON

SET LAMP

MAIN switch: ON
When vehicle speed is between 40 km/h (25 MPH) and
144 km/h (89 MPH)

SPECIFICATION
ON OFF

ASCD: Operating

ON

ASCD: Not operating

OFF

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-480, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734304

1.CHECK DTC
Check that DTC U1000 or U1001 is not displayed.
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Perform trouble diagnosis for DTC U1000, U1001. Refer to EC-146, "Diagnosis Procedure".

2.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".
Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace combination meter.
NO
>> Repair or replace.

Revision: 2007 June

EC-480

G37 Coupe

COOLING FAN
[VQ37VHR]

< COMPONENT DIAGNOSIS >

COOLING FAN

Description

INFOID:0000000001734305

COOLING FAN CONTROL MODULE

EC

Cooling fan control module receives ON/OFF pulse duty signal from IPDM E/R. Corresponding to this ON/OFF
pulse duty signal, cooling fan control module sends cooling fan motor operating voltage to cooling fan motor.
The revolution speed of cooling fan motor is controlled by duty cycle of the voltage.

COOLING FAN MOTOR

Cooling fan motor receives cooling fan motor operating voltage from cooling fan control module. The revolution speed of cooling fan motor is controlled by duty cycle of the voltage.

Component Function Check

INFOID:0000000001734306

1.CHECK COOLING FAN FUNCTION

With CONSULT-III
Turn ignition switch ON.
Perform FAN DUTY CONTROL in ACTIVE TEST mode with CONSULT-III.
Make sure that cooling fan speed varies according to the percent.
Without CONSULT-III
1. Perform IPDM E/R auto active test and check cooling fan motors operation, refer to PCS-11, "Diagnosis
Description".
2. Make sure that cooling fan operates.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-481, "Diagnosis Procedure".

1.
2.
3.

Diagnosis Procedure

Connector

Terminal

E37

Ground

Voltage

Ground

Battery voltage

Turn ignition switch OFF.

Check the continuity between cooling fan control module harness connector and ground.

Connector

Terminal

E37

Ground

Continuity

Ground

Existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair open circuit or short to power in harness or connectors.
Revision: 2007 June

2.CHECK COOLING FAN CONTROL MODULE GROUND CIRCUIT

Cooling fan control module

Is the inspection result normal?

YES >> GO TO 2.
NO
>> GO TO 7.
1.
2.

Turn ignition switch OFF.

Disconnect cooling fan control module harness connector E37.
Turn ignition switch ON.
Check the voltage between cooling fan control module harness connector and ground.

Cooling fan control module

INFOID:0000000001734307

1.CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-I

1.
2.
3.
4.

EC-481

G37 Coupe

COOLING FAN
[VQ37VHR]

< COMPONENT DIAGNOSIS >

3.CHECK IPDM E/R GROUND CIRCUIT

1.
2.

Disconnect IPDM E/R harness connectors E5, E6.

Check the continuity between IPDM E/R harness connector and ground.
IPDM E/R

Connector

Terminal

E5

12

E6

41

Ground

Continuity

Ground

Existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 4.
NO
>> Repair open circuit or short to power in harness or connectors.

4.CHECK COOLING FAN CONTROL SIGNAL CIRCUIT

1.
2.

Disconnect IPDM E/R harness connector E9.

Check the continuity between IPDM E/R harness connector and cooling fan control module harness connector.
IPDM E/R

Cooling fan control module

Connector

Terminal

Connector

Terminal

E9

97

E37

Continuity
Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK COOLING FAN CONTROL MODULE OUTPUT SIGNAL CIRCUIT

1.
2.
3.
4.

Reconnect all harness connectors disconnected.

Disconnect cooling fan control module harness connectors E301, E302.
Turn ignition switch ON.
Check the voltage between cooling fan control module harness connector and ground.

Cooling fan control module

Connector

Terminal

E301

E302

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 6.
NO
>> Replace cooling fan control module.

6.CHECK COOLING FAN MOTORS -1 AND -2

Refer to EC-483, "Component Inspection (Cooling Fan Motor)".
Is the inspection result normal?
YES >> GO TO 11.
NO
>> Replace cooling fan motor.

7.CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-II

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect cooling fan relay harness connector.
Turn ignition switch ON.
Check the voltage between cooling fan relay harness connector and ground.

Revision: 2007 June

EC-482

G37 Coupe

COOLING FAN
[VQ37VHR]

< COMPONENT DIAGNOSIS >

Cooling fan relay
Connector

Terminal
1

E17

A
Ground

Voltage

Ground

Battery voltage

EC

Is the inspection result normal?

YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

D

Check the following.

10A fuse (No. 42)
IPDM E/R harness connector E7
50A fusible link (letter F)
Harness for open or short between cooling fan relay and fuse
Harness for open or short between cooling fan relay and battery

>> Repair open circuit or short to ground or short to power in harness or connectors.

9.CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-III

1.
2.
3.

Turn ignition switch OFF.

Disconnect IPDM E/R harness connector E6.
Check the continuity between cooling fan relay harness connector and IPDM E/R harness connector.
Cooling fan relay

IPDM E/R

Connector

Terminal

Connector

Terminal

E17

E6

42

4.

I
Existed

Cooling fan control module

Connector

Terminal

Connector

Terminal

E17

E37

Continuity
Existed

10.CHECK COOLING FAN RELAY

Refer to EC-484, "Component Inspection (Cooling Fan Relay)".
Is the inspection result normal?
YES >> GO TO 11.
NO
>> Replace cooling fan relay.

11.CHECK INTERMITTENT INCIDENT

Perform GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair or replace harness connectors.

Component Inspection (Cooling Fan Motor)

INFOID:0000000001734308

1.CHECK COOLING FAN MOTOR

Turn ignition switch OFF.

Revision: 2007 June

5. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 10.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

1.

Continuity

Check the continuity between cooling fan relay harness connector and cooling fan control module harness
connector.
Cooling fan relay

EC-483

G37 Coupe

COOLING FAN
< COMPONENT DIAGNOSIS >
2. Disconnect cooling fan control module harness connectors E301, E302.
3. Supply cooling fan control module terminals with battery voltage and check operation.

[VQ37VHR]

Cooling fan control module

Motor

Connector

1
2

Terminal
(+)

()

E301

E302

Operation

Cooling fan operates.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace cooling fan motor.

Component Inspection (Cooling Fan Relay)

INFOID:0000000001734309

1.CHECK COOLING FAN RELAY

1.
2.
3.

Turn ignition switch OFF.

Remove cooling fan relay.
Check the continuity between cooling fan relay terminals under
the following conditions.

Terminals
3 and 5

Conditions

Continuity

12V direct current supply between terminals 1 and 2

No current supply

Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace cooling fan relay.
JMBIA0876ZZ

Revision: 2007 June

EC-484

G37 Coupe

ELECTRICAL LOAD SIGNAL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ELECTRICAL LOAD SIGNAL

Description

INFOID:0000000001734310

The electrical load signal (Headlamp switch signal, rear window defogger switch signal, etc.) is transferred EC
through the CAN communication line from BCM to ECM via IPDM E/R.

Component Function Check

INFOID:0000000001734311

1.CHECK REAR WINDOW DEFOGGER SWITCH FUNCTION

1.
2.
3.

Turn ignition switch ON.

Connect CONSULT-III and select DATA MONITOR mode.
Select LOAD SIGNAL and check indication under the following conditions.
Monitor item

LOAD SIGNAL

Condition
Rear window defogger switch

Indication
ON

ON

OFF

OFF

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Go to EC-485, "Diagnosis Procedure".

2.CHECK LIGHTING SWITCH FUNCTION

Check LOAD SIGNAL indication under the following conditions.
Monitor item
LOAD SIGNAL

Condition
Lighting switch

Indication

ON at 2nd position

ON

OFF

OFF

Is the inspection result normal?

YES >> GO TO 3.
NO
>> Go to EC-485, "Diagnosis Procedure".

3.CHECK HEATER FAN CONTROL SWITCH FUNCTION

Select HEATER FAN SW and check indication under the following conditions.
Monitor item
HEATER FAN SW

Condition
Heater fan control switch

Indication
ON

ON

OFF

OFF

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-485, "Diagnosis Procedure".

Diagnosis Procedure

N
INFOID:0000000001734312

1.INSPECTION START

Confirm the malfunctioning circuit (rear window defogger, headlamp or heater fan). Refer to EC-485, "Component Function Check".
Which circuit is related to the incident?
Rear window defogger>>GO TO 2.
Headlamp>>GO TO 3.
Heater fan>>GO TO 4.

2.CHECK REAR WINDOW DEFOGGER SYSTEM

Refer to DEF-3, "Work Flow".

Revision: 2007 June

EC-485

G37 Coupe

ELECTRICAL LOAD SIGNAL

[VQ37VHR]

< COMPONENT DIAGNOSIS >

>> INSPECTION END

3.CHECK HEADLAMP SYSTEM

Refer to EXL-5, "Work Flow".
>> INSPECTION END

4.CHECK HEATER FAN CONTROL SYSTEM

Refer to HAC-5, "Work Flow".
>> INSPECTION END

Revision: 2007 June

EC-486

G37 Coupe

FUEL INJECTOR
[VQ37VHR]

< COMPONENT DIAGNOSIS >

FUEL INJECTOR

Description

INFOID:0000000001734313

The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the fuel injector circuit, the coil in the fuel injector is energized. The energized coil pulls the ball valve back and
allows fuel to flow through the fuel injector into the intake manifold.
The amount of fuel injected depends upon the injection pulse duration. Pulse duration is the length of time the fuel injector remains
open. The ECM controls the injection pulse duration based on
engine fuel needs.

EC

SEF375Z

Component Function Check

INFOID:0000000001734314

1.INSPECTION START

Turn ignition switch to START.

Is any cylinder ignited?
YES >> GO TO 2.
NO
>> Go to EC-487, "Diagnosis Procedure".

2.CHECK FUEL INJECTOR FUNCTION

With CONSULT-III
Start engine.
Perform POWER BALANCE in ACTIVE TEST mode with CONSULT-III.
Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Start engine.
2. Listen to each fuel injector operating sound.

1.
2.
3.

Clicking sound should be heard.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-487, "Diagnosis Procedure".

M
PBIB3332E

Diagnosis Procedure

INFOID:0000000001734315

1.CHECK FUEL INJECTOR POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect fuel injector harness connector.
Turn ignition switch ON.
Check the voltage between fuel injector harness connector and ground.

Revision: 2007 June

EC-487

G37 Coupe

FUEL INJECTOR
[VQ37VHR]

< COMPONENT DIAGNOSIS >

Fuel injector
Cylinder

Connector

Terminal

F121

F122

F123

F124

F125

F126

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 3.
NO
>> GO TO 2.

2.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
Harness connectors F10, F120
IPDM E/R harness connector E7
10A fuse (No. 44)
Harness for open or short between fuel injector and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.

3.CHECK FUEL INJECTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between fuel injector harness connector and ECM harness connector.
Fuel injector

ECM

Cylinder

Connector

Terminal

Connector

Terminal

F121

89

F122

85

F123

F124

F125

86

F126

82

F102

81
90

Continuity

Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 5.
NO
>> GO TO 4

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors F106, F107
Harness connectors F10, F120
Harness for open or short between fuel injector and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK FUEL INJECTOR

Refer to EC-489, "Component Inspection".
Is the inspection result normal?
Revision: 2007 June

EC-488

G37 Coupe

FUEL INJECTOR
[VQ37VHR]

< COMPONENT DIAGNOSIS >

YES >> GO TO 6.
NO
>> Replace malfunctioning fuel injector.

6.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

Component Inspection

EC

C
INFOID:0000000001734316

1.CHECK FUEL INJECTOR

1.
2.
3.

Turn ignition switch OFF.

Disconnect fuel injector harness connector.
Check resistance between fuel injector terminals as follows.

Terminals

Resistance

1 and 2

11.1 - 14.3 [at 10 - 60C (60 - 140F)]

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace malfunctioning fuel injector.

Revision: 2007 June

EC-489

G37 Coupe

FUEL PUMP
[VQ37VHR]

< COMPONENT DIAGNOSIS >

FUEL PUMP
Description

INFOID:0000000001734317

Sensor

Input signal to ECM

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)

Engine speed*

Battery

Battery voltage*

ECM Function

Actuator

Fuel pump control

Fuel pump relay

Fuel pump

*: ECM determines the start signal status by the signals of engine speed and battery voltage.

The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine
startability. If the ECM receives a engine speed signal from the camshaft position sensor (PHASE), it knows
that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when
the ignition switch is ON, the engine stalls. The ECM stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump
relay, which in turn controls the fuel pump.
Condition

Fuel pump operation

Ignition switch is turned to ON.

Operates for 1 second.

Engine running and cranking

Operates.

When engine is stopped

Stops in 1.5 seconds.

Except as shown above

Stops.

Component Function Check

INFOID:0000000001734318

1.CHECK FUEL PUMP FUNCTION

1.
2.

Turn ignition switch ON.

Pinch fuel feed hose (1) with two fingers.
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> EC-490, "Diagnosis Procedure".

JMBIA0849ZZ

Diagnosis Procedure

INFOID:0000000001734319

1.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Turn ignition switch ON.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

F101

22

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 2.

2.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II

Revision: 2007 June

EC-490

G37 Coupe

FUEL PUMP
< COMPONENT DIAGNOSIS >
Check the voltage between IPDM E/R harness connector and ground.

[VQ37VHR]
A

IPDM E/R
Connector

Terminal

E7

77

Ground

Voltage

Ground

Battery voltage

EC

Is the inspection result normal?

YES >> GO TO 3.
NO
>> GO TO 10.

3.DETECT MALFUNCTIONING PART

D

Check the following.

Harness connectors E3, F1
Harness connectors F104, F105
Harness for open or short between IPDM E/R and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III

1.
2.
3.
4.
5.

Turn ignition switch OFF.

Reconnect all harness connectors disconnected.
Disconnect fuel level sensor unit and fuel pump harness connector.
Turn ignition switch ON.
Check the voltage between fuel level sensor unit and fuel pump harness connector and ground.

H
Fuel level sensor unit and
fuel pump
Connector

Terminal

B22

Ground

Voltage

I
Ground

Battery voltage should exist for 1 second

after ignition switch is turned ON.

Is the inspection result normal?

YES >> GO TO 8.
NO
>> GO TO 5.

5.CHECK 15A FUSE

1. Turn ignition switch OFF.
2. Disconnect 15A fuse (No. 41) from IPDM E/R.
3. Check 15A fuse.
Is the inspection result normal?
YES >> GO TO 6.
NO
>> Replace fuse.

6.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-IV

1.
2.

Disconnect IPDM E/R harness connector E5.

Check the continuity between IPDM E/R harness connector and fuel level sensor unit and fuel pump
harness connector.

O
Fuel level sensor unit
and fuel pump

IPDM E/R
Connector

Terminal

Connector

Terminal

E5

13

B22

Continuity

P
Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 10.
NO
>> GO TO 7.
Revision: 2007 June

EC-491

G37 Coupe

FUEL PUMP
[VQ37VHR]

< COMPONENT DIAGNOSIS >

7.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E104, B4
IPDM E/R harness connector E5
Harness for open or short between IPDM E/R and fuel level sensor unit and fuel pump
>> Repair open circuit or short to power in harness or connectors.

8.CHECK FUEL PUMP GROUND CIRCUIT

1.
2.
3.

Turn ignition switch OFF.

Disconnect dropping resistor harness connector.
Check the continuity between fuel level sensor unit and fuel pump harness connector and ground.

Fuel level sensor unit

and fuel pump
Connector

Terminal

B22

Ground

Continuity

Ground

Existed

4. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 9.
NO
>> Repair open circuit or short to power in harness or connectors.

9.CHECK FUEL PUMP

Refer to EC-492, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 10.
NO
>> Replace fuel pump.

10.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO
>> Repair or replace harness or connectors.

Component Inspection

INFOID:0000000001734320

1.CHECK FUEL PUMP

1.
2.
3.

Turn ignition switch OFF.

Disconnect fuel level sensor unit and fuel pump harness connector.
Check resistance between fuel level sensor unit and fuel pump terminals as follows.

Terminals

Resistance

1 and 3

0.2 - 5.0 [at 25C (77F)]

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace fuel level sensor unit and fuel pump

Revision: 2007 June

EC-492

G37 Coupe

ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ICC BRAKE SWITCH

Description

INFOID:0000000001911045

When the brake pedal is depressed, ICC brake switch is turned OFF and stop lamp switch is turned ON. ECM EC
detects the state of the brake pedal by this input of two kinds (ON/OFF signal).
Refer to CCS-15, "System Description" for the ICC function.

Component Function Check

INFOID:0000000001734322

1.CHECK ICC BRAKE SWITCH FUNCTION

D

With CONSULT-III
1. Turn ignition switch ON.
2. Select BRAKE SW1 in DATA MONITOR mode with CONSULT-III.
3. Check BRAKE SW1 indication under the following conditions.
Monitor item
BRAKE SW1

Condition
Brake pedal (A/T)
Brake pedal and clutch pedal (M/T)

Indication
Slightly depressed

OFF

Fully released

ON

Without CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector and ground.

H
ECM

Ground

Connector

Terminal

M107

126
(ICC brake switch signal)

Condition

Voltage

I
Ground

Brake pedal (A/T)

Brake pedal and clutch pedal (M/T)

Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-493, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734323

1.INSPECTION START

Check which type of transmission the vehicle is equipped with.

Which type of transmission?
A/T
>> GO TO 2.
M/T
>> GO TO 7.

2.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ICC brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ICC brake switch harness connector and ground.
ICC brake switch

Connector

Terminal

E114

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

3.DETECT MALFUNCTIONING PART

Revision: 2007 June

EC-493

G37 Coupe

ICC BRAKE SWITCH

< COMPONENT DIAGNOSIS >
Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ICC brake switch and fuse

[VQ37VHR]

>> Repair open circuit or short to ground in harness or connectors.

4.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ICC brake switch harness connector and ECM harness connector.
ICC brake switch

ECM

Connector

Terminal

Connector

Terminal

E114

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness for open or short between ICC brake switch and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK ICC BRAKE SWITCH

Refer to EC-496, "Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace ICC brake switch.

7.CHECK ICC BRAKE SWITCH CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ICC brake switch harness connector.
Turn ignition switch ON.
Check the voltage between ICC brake switch harness connector and ground.
ICC brake switch

Connector

Terminal

E114

Ground

Ground

Condition

Brake pedal

Voltage

Slightly depressed
Fully released

Approx. 0V
Battery voltage

Is the inspection result normal?

YES >> GO TO 12.
NO
>> GO TO 8.

8.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT

1.
2.
3.
4.

Turn ignition switch OFF.

Disconnect ICC clutch switch harness connector.
Turn ignition switch ON.
Check the voltage between ICC clutch switch harness connector and ground.

Revision: 2007 June

EC-494

G37 Coupe

ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ICC clutch switch
Connector

Terminal

E113

A
Ground

Voltage

Ground

Battery voltage

EC

Is the inspection result normal?

YES >> GO TO 10.
NO
>> GO TO 9.

9.DETECT MALFUNCTIONING PART

Check the following.
Fuse block (J/B) connector E103
10A fuse (No. 3)
Harness for open or short between ICC clutch switch and fuse

>> Repair open circuit or short to ground in harness or connectors.

10.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Turn ignition switch OFF.

Check the continuity between ICC clutch switch harness connector and ICC brake switch harness connector.
ICC clutch switch

ICC brake switch

Connector

Terminal

Connector

Terminal

E113

E114

Continuity

H
Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 11.
NO
>> Repair open circuit or short to ground or short to power in harness or connectors.

11.CHECK ICC CLUTCH SWITCH

Refer to EC-496, "Component Inspection (ICC Clutch Switch)".

Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace ICC clutch switch.

12.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between ICC brake switch harness connector and ECM harness connector.
ICC brake switch

ECM

Connector

Terminal

Connector

Terminal

E109

M107

126

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 14.
NO
>> GO TO 13.

13.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E106, M6
Harness for open or short between ICC brake switch and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
Revision: 2007 June

EC-495

G37 Coupe

ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

14.CHECK ICC BRAKE SWITCH

Refer to EC-496, "Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace ICC brake switch.

15.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
>> INSPECTION END

Component Inspection (ICC Brake Switch)

INFOID:0000000001911046

1.CHECK ICC BRAKE SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ICC brake switch harness connector.
Check the continuity between ICC brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Fully released

Brake pedal

Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ICC BRAKE SWITCH-II

1.
2.

Adjust ICC brake switch installation. Refer to BR-7, "Inspection and Adjustment".
Check the continuity between ICC brake switch terminals under the following conditions.

Terminals
1 and 2

Condition
Fully released

Brake pedal

Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ICC brake switch.

Component Inspection (ICC Clutch Switch)

INFOID:0000000001911047

1.CHECK ICC CLUTCH SWITCH-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ICC clutch switch harness connector.
Check the continuity between ICC clutch switch terminals under the following conditions.

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

Is the inspection result normal?

YES >> INSPECTION END
NO
>> GO TO 2.

2.CHECK ICC CLUTCH SWITCH-II

1.
2.

Adjust ICC clutch switch installation. Refer to CL-5, "Inspection and Adjustment".
Check the continuity between ICC clutch switch terminals under the following conditions.

Revision: 2007 June

EC-496

G37 Coupe

ICC BRAKE SWITCH

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Terminals
1 and 2

Condition
Clutch pedal

Fully released
Slightly depressed

Continuity
Existed
Not existed

EC

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace ICC clutch switch.

Revision: 2007 June

EC-497

G37 Coupe

IGNITION SIGNAL
[VQ37VHR]

< COMPONENT DIAGNOSIS >

IGNITION SIGNAL
Description

INFOID:0000000001734326

The ignition signal from the ECM is sent to and amplified by the power transistor. The power transistor turns
ON and OFF the ignition coil primary circuit. This ON/OFF operation induces the proper high voltage in the coil
secondary circuit.

Component Function Check

INFOID:0000000001734327

1.INSPECTION START
Turn ignition switch OFF, and restart engine.
Does the engine start?
YES-1 >> With CONSULT-III: GO TO 2.
YES-2 >> Without CONSULT-III: GO TO 3.
No
>> Go to EC-498, "Diagnosis Procedure".

2.CHECK IGNITION SIGNAL FUNCTION

With CONSULT-III
1. Perform POWER BALANCE in ACTIVE TEST mode with CONSULT-III.
2. Make sure that each circuit produces a momentary engine speed drop.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-498, "Diagnosis Procedure".

3.CHECK IGNITION SIGNAL FUNCTION

1.
2.

Without CONSULT-III
Let engine idle.
Read the voltage signal between ECM harness connector and ground with an oscilloscope.
ECM

Connector

Terminal

Ground

Voltage signal

11
12
15
F101

16

Ground

19
20

JMBIA0035GB

NOTE:
The pulse cycle changes depending on rpm at idle.

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-498, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734328

1.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I

1.
2.

Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
Check the voltage between ECM harness connector and ground.
ECM

Connector

Terminal

M107

125

Revision: 2007 June

Ground

Voltage

Ground

Battery voltage

EC-498

G37 Coupe

IGNITION SIGNAL
< COMPONENT DIAGNOSIS >
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Go to EC-140, "Diagnosis Procedure".

[VQ37VHR]
A

2.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II

1.
2.
3.
4.

EC

Turn ignition switch OFF.

Disconnect condenser harness connector.
Turn ignition switch ON.
Check the voltage between condenser harness connector and ground.
Condenser

Connector

Terminal

F8

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 5.
NO
>> GO TO 3.

3.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III

1.
2.
3.

Turn ignition switch OFF.

Disconnect IPDM E/R harness connector E7.
Check the continuity between IPDM E/R harness connector and condenser harness connector.
IPDM E/R

Condenser

Connector

Terminal

Connector

Terminal

E7

53

F8

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> Go to EC-140, "Diagnosis Procedure".
NO
>> GO TO 4.

4.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors E3, F1
Harness for open or short between IPDM E/R and condenser

>> Repair open circuit or short to ground or short to power in harness or connectors.

5.CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.

Turn ignition switch OFF.

Check the continuity between condenser harness connector and ground.

Condenser
Connector

Terminal

F8

Ground

Continuity

Ground

Existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> Repair open circuit or short to power in harness or connectors.

6.CHECK CONDENSER
Refer to EC-502, "Component Inspection (Condenser)"
Is the inspection result normal?
YES >> GO TO 7.
NO
>> Replace condenser.
Revision: 2007 June

EC-499

G37 Coupe

IGNITION SIGNAL
[VQ37VHR]

< COMPONENT DIAGNOSIS >

7.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV

1.
2.
3.
4.

Reconnect all harness connectors disconnected.

Disconnect ignition coil harness connector.
Turn ignition switch ON.
Check the voltage between ignition coil harness connector and ground.
Ignition coil

Cylinder

Connector

Terminal

F11

F12

F13

F14

F15

F16

Ground

Voltage

Ground

Battery voltage

Is the inspection result normal?

YES >> GO TO 9.
NO
>> GO TO 8.

8.DETECT MALFUNCTIONING PART

Check the following.
Harness connector F1
Harness for open or short between ignition coil and harness connector F1
>> Repair or replace harness or connectors.

9.CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT

1.
2.

Turn ignition switch OFF.

Check the continuity between ignition coil harness connector and ground.
Ignition coil

Cylinder

Connector

Terminal

F11

F12

F13

F14

F15

F16

Ground

Continuity

Ground

Existed

3. Also check harness for short to power.

Is the inspection result normal?
YES >> GO TO 10.
NO
>> Repair open circuit or short to power in harness or connectors.

10.CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
2.

Disconnect ECM harness connector.

Check the continuity between ignition coil harness connector and ECM harness connector.

Revision: 2007 June

EC-500

G37 Coupe

IGNITION SIGNAL
[VQ37VHR]

< COMPONENT DIAGNOSIS >

Ignition coil

ECM

Cylinder

Connector

Terminal

Connector

Terminal

F11

20

F12

16

F13

F14

F15

15

F16

19

F101

12
11

Continuity

EC
Existed

3. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 12.
NO
>> GO TO 11.

11.DETECT MALFUNCTIONING PART

F

Check the following.

Harness connectors F104, F105
Harness for open or short between ignition coil and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

12.CHECK IGNITION COIL WITH POWER TRANSISTOR

Refer to EC-501, "Component Inspection (Ignition Coil with Power Transistor)".

Is the inspection result normal?
YES >> GO TO 13.
NO
>> Replace malfunctioning ignition coil with power transistor.

13.CHECK INTERMITTENT INCIDENT

J

Refer to GI-38, "Intermittent Incident".

>> INSPECTION END

Component Inspection (Ignition Coil with Power Transistor)

INFOID:0000000001734329

1.CHECK IGNITION COIL WITH POWER TRANSISTOR-I

1.
2.
3.

Turn ignition switch OFF.

Disconnect ignition coil harness connector.
Check resistance between ignition coil terminals as follows.
Terminals

Resistance [at 25C (77F)]

1 and 2

Except 0 or

1 and 3
2 and 3

Except 0

Is the inspection result normal?

YES >> GO TO 2.
NO
>> Replace malfunctioning ignition coil with power transistor.

2.CHECK IGNITION COIL WITH POWER TRANSISTOR-II

CAUTION:
Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.

Revision: 2007 June

EC-501

G37 Coupe

IGNITION SIGNAL
< COMPONENT DIAGNOSIS >
3. Remove fuel pump fuse (1) in IPDM E/R (2) to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following procedure.
4. Start engine.
5. After engine stalls, crank it two or three times to release all fuel
pressure.
6. Turn ignition switch OFF.
7. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
8. Remove ignition coil and spark plug of the cylinder to be
checked.
9. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
10. Connect spark plug and harness connector to ignition coil.
11. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
12. Crank engine for about three seconds, and check whether spark
is generated between the spark plug and the grounded metal
portion.

[VQ37VHR]

JMBIA0021ZZ

Spark should be generated.

CAUTION:
Do not approach to the spark plug and the ignition coil
JMBIA0066GB
within 50 cm (19.7 in). Be careful not to get an electrical
shock while checking, because the electrical discharge
voltage becomes 20kV or more.
It might cause to damage the ignition coil if the gap of more than 17 mm 0.66 in) is taken.
NOTE:
When the gap is less than 13 mm (0.52 in), the spark might be generated even if the coil is malfunctioning.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace malfunctioning ignition coil with power transistor.

Component Inspection (Condenser)

INFOID:0000000001734330

1.CHECK CONDENSER
1.
2.
3.

Turn ignition switch OFF.

Disconnect condenser harness connector.
Check resistance between condenser terminals as follows.

Terminals

Resistance

1 and 2

Above 1 M [at 25C (77F)]

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace condenser.

Revision: 2007 June

EC-502

G37 Coupe

MALFUNCTION INDICATOR LAMP

[VQ37VHR]

< COMPONENT DIAGNOSIS >

MALFUNCTION INDICATOR LAMP

Description

A
INFOID:0000000001734331

The Malfunction Indicator Lamp (MIL) is located on the combination

meter.
The MIL will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
When the engine is started, the MIL should go off. If the MIL remains
on, the on board diagnostic system has detected an engine system
malfunction.
For details, refer to EC-107, "Diagnosis Description".

EC

SEF217U

Component Function Check

INFOID:0000000001734332

1.CHECK MIL FUNCTION

1. Turn ignition switch ON.

2. Make sure that MIL lights up.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Go to EC-503, "Diagnosis Procedure".

Diagnosis Procedure

H
INFOID:0000000001734333

1.CHECK DTC

Check that DTC U1000 or U1001 is not displayed.

Is the inspection result normal?
YES >> GO TO 2.
NO
>> Perform trouble diagnosis for DTC U1000, U1001. Refer to EC-146, "Diagnosis Procedure".

2.CHECK DTC WITH UNIFIED METER AND A/C AMP.

Refer to MWI-37, "CONSULT-III Function (METER/M&A)".

Is the inspection result normal?
YES >> GO TO 3.
NO
>> Repair or replace.

3.CHECK INTERMITTENT INCIDENT

M

Refer to GI-38, "Intermittent Incident".

Is the inspection result normal?
YES >> Replace combination meter.
NO
>> Repair or replace.

Revision: 2007 June

EC-503

G37 Coupe

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

Description

INFOID:0000000001734334

PBIB1068E

From the beginning of refueling, the air and vapor inside the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
Put a CAUTION: FLAMMABLE sign in workshop.
Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
Be sure to furnish the workshop with a CO2 fire extinguisher.
CAUTION:
Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-proof container and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-601, "Inspection".
- Disconnect battery ground cable.
Always replace O-ring when the fuel gauge retainer is removed.
Do not kink or twist hose and tube when they are installed.
Do not tighten hose and clamps excessively to avoid damaging hoses.
After installation, run engine and check for fuel leaks at connection.
Do not attempt to top off the fuel tank after the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, resulting in fuel spray and possibly a fire.

Component Function Check

INFOID:0000000001734335

1.CHECK ORVR FUNCTION

Check whether the following symptoms are present.
Fuel odor from EVAP canister is strong.
Cannot refuel/Fuel odor from the fuel filler opening is strong while refueling.
Is any symptom present?
YES >> Go to EC-504, "Diagnosis Procedure".
NO
>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734336

1.INSPECTION START
Check whether the following symptoms are present.
A: Fuel odor from EVAP canister is strong.
Revision: 2007 June

EC-504

G37 Coupe

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

< COMPONENT DIAGNOSIS >
B: Cannot refuel/Fuel odor from the fuel filler opening is strong while refueling.
Which symptom is present?
A
>> GO TO 2.
B
>> GO TO 7.

[VQ37VHR]
A

2.CHECK EVAP CANISTER

EC

1.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES >> GO TO 3.
NO
>> GO TO 4.

3.CHECK IF EVAP CANISTER SATURATED WITH WATER

Check if water will drain from EVAP canister (1).
2

: EVAP canister vent control valve

Does water drain from the EVAP canister?

YES >> GO TO 4.
NO
>> GO TO 6.

H
PBIB2731E

4.REPLACE EVAP CANISTER

Replace EVAP canister with a new one.

J

>> GO TO 5.

5.DETECT MALFUNCTIONING PART

K

Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
>> Repair or replace EVAP hose.

6.CHECK REFUELING EVAP VAPOR CUT VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

7.CHECK EVAP CANISTER

1.

Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
Is the inspection result normal?
YES >> GO TO 8.
NO
>> GO TO 9.

8.CHECK IF EVAP CANISTER SATURATED WITH WATER

Revision: 2007 June

EC-505

G37 Coupe

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

[VQ37VHR]

< COMPONENT DIAGNOSIS >

Check if water will drain from EVAP canister (1).
2

: EVAP canister vent control valve

Does water drain from the EVAP canister?

YES >> GO TO 9.
NO
>> GO TO 11.

PBIB2731E

9.REPLACE EVAP CANISTER

Replace EVAP canister with a new one.
>> GO TO 10.

10.DETECT MALFUNCTIONING PART

Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
>> Repair or replace EVAP hose.

11.CHECK VENT HOSES AND VENT TUBES

Check hoses and tubes between EVAP canister and refueling control valve for clogging, kink, looseness and
improper connection.
Is the inspection result normal?
YES >> GO TO 12.
NO
>> Repair or replace hoses and tubes.

12.CHECK FILLER NECK TUBE

Check recirculation line for clogging, dents and cracks.
Is the inspection result normal?
YES >> GO TO 13.
NO
>> Replace filler neck tube.

13.CHECK REFUELING EVAP VAPOR CUT VALVE

Refer to EC-507, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 14.
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

14.CHECK FUEL FILLER TUBE

Check filler neck tube and hose connected to the fuel tank for clogging, dents and cracks.
Is the inspection result normal?
YES >> GO TO 15.
NO
>> Replace fuel filler tube.

15.CHECK ONE-WAY FUEL VALVE-I

Check one-way valve for clogging.
Is the inspection result normal?
YES >> GO TO 16.
NO
>> Repair or replace one-way fuel valve with fuel tank.

16.CHECK ONE-WAY FUEL VALVE-II

1.
2.

Make sure that fuel is drained from the tank.

Remove fuel filler tube and hose.

Revision: 2007 June

EC-506

G37 Coupe

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

< COMPONENT DIAGNOSIS >
3. Check one-way fuel valve for operation as follows.
When a stick is inserted, the valve should open, when removing
stick it should close.
Do not drop any material into the tank.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace fuel filler tube or replace one-way fuel valve
with fuel tank.

[VQ37VHR]
A

EC

C
SEF665U

Component Inspection

INFOID:0000000001734337

1.INSPECTION START

Do you have CONSULT-III?

Do you have CONSULT-III?
YES >> GO TO 2.
NO
>> GO TO 3.

2.CHECK REFUELING EVAP VAPOR CUT VALVE

With CONSULT-III
1. Turn ignition switch OFF.
2. Remove fuel tank. Refer to FL-10, "Removal and Installation".
3. Drain fuel from the tank as follows:
Remove fuel feed hose located on the fuel gauge retainer.
Connect a spare fuel hose, one side to fuel gauge retainer where the hose was removed and the other
side to a fuel container.
Drain fuel using FUEL PUMP RELAY in ACTIVE TEST mode with CONSULT-III.
4. Check refueling EVAP vapor cut valve for being stuck to close as follows.
Blow air into the refueling EVAP vapor cut valve (from the end of EVAP/ORVR line hose), and check that
the air flows freely into the tank.
5. Check refueling EVAP vapor cut valve for being stuck to open as follows.
Connect vacuum pump to hose end.
Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
Put fuel tank upside down.
Apply vacuum pressure to hose end [13.3 kPa (0.136 kg/cm3, 1.93 psi)] with fuel gauge retainer
remaining open and check that the pressure is applicable.

PBIB1035E

Is the inspection result normal?

YES >> INSPECTION END
Revision: 2007 June

EC-507

G37 Coupe

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

< COMPONENT DIAGNOSIS >
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

[VQ37VHR]

3.CHECK REFUELING EVAP VAPOR CUT VALVE

Without CONSULT-III
Turn ignition switch OFF.
Remove fuel tank. Refer to FL-10, "Removal and Installation".
Drain fuel from the tank as follows:
Remove fuel gauge retainer.
Drain fuel from the tank using a handy pump into a fuel container.
Check refueling EVAP vapor cut valve for being stuck to close as follows.
Blow air into the refueling EVAP vapor cut valve (from the end of EVAP/ORVR line hose), and check that
the air flows freely into the tank.
5. Check refueling EVAP vapor cut valve for being stuck to open as follows.
Connect vacuum pump to hose end.
Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
Put fuel tank upside down.
Apply vacuum pressure to hose end [13.3 kPa (0.136 kg/cm3, 1.93 psi)] with fuel gauge retainer
remaining open and check that the pressure is applicable.
1.
2.
3.
4.

PBIB1035E

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Replace refueling EVAP vapor cut valve with fuel tank.

Revision: 2007 June

EC-508

G37 Coupe

POSITIVE CRANKCASE VENTILATION

[VQ37VHR]

< COMPONENT DIAGNOSIS >

POSITIVE CRANKCASE VENTILATION

Description

INFOID:0000000001734338

EC

G
JMBIA0858ZZ

1.

PCV valve

2.

Electric throttle control actuator

A.

Normal condition

B.

Hi-load condition

3.

Mass air flow sensor

: Fresh air
: Blow-by air

This system returns blow-by gas to the intake manifold.

The positive crankcase ventilation (PCV) valve is provided to conduct crankcase blow-by gas to the intake
manifold.
During partial throttle operation of the engine, the intake manifold sucks the blow-by gas through the PCV
valve.
Normally, the capacity of the valve is sufficient to handle any blow-by and a small amount of ventilating air.
The ventilating air is then drawn from the air inlet tubes into the crankcase. In this process the air passes
through the hose connecting air inlet tubes to rocker cover.
Under full-throttle condition, the manifold vacuum is insufficient to draw the blow-by flow through the valve.
The flow goes through the hose connection in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not
meet the requirement. This is because some of the flow will go
through the hose connection to the air inlet tubes under all conditions.

O
PBIB1588E

Component Inspection

INFOID:0000000001734339

1.CHECK PCV VALVE

Revision: 2007 June

EC-509

G37 Coupe

POSITIVE CRANKCASE VENTILATION

< COMPONENT DIAGNOSIS >
With engine running at idle, remove PCV valve from rocker cover. A
properly working valve makes a hissing noise as air passes through
it. A strong vacuum should be felt immediately when a finger is
placed over valve inlet.
Is the inspection result normal?
YES >> INSPECTION END
NO
>> Replace PCV valve.

[VQ37VHR]

PBIB1589E

Revision: 2007 June

EC-510

G37 Coupe

REFRIGERANT PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

REFRIGERANT PRESSURE SENSOR

Description

INFOID:0000000001734340

The refrigerant pressure sensor is installed at the condenser of the air conditioner system. The sensor uses an EC
electrostatic volume pressure transducer to convert refrigerant pressure to voltage. The voltage signal is sent
to ECM, and ECM controls cooling fan system.
C

E
PBIB2657E

Component Function Check

INFOID:0000000001734341

1.CHECK REFRIGERANT PRESSURE SENSOR FUNCTION

1.
2.
3.

Start engine and warm it up to normal operating temperature.

Turn A/C switch and blower fan switch ON.
Check the voltage between ECM harness connector and ground.
ECM

Ground

Connector

Terminal

M107

105
(Refrigerant pressure sensor signal)

Voltage

I
Ground

1.0 - 4.0V

Is the inspection result normal?

YES >> INSPECTION END
NO
>> Go to EC-511, "Diagnosis Procedure".

Diagnosis Procedure

INFOID:0000000001734342

1.CHECK GROUND CONNECTION

1. Turn A/C switch and blower fan switch OFF.

2. Turn ignition switch OFF.
3. Check ground connection M95. Refer to Ground Inspection in GI-41, "Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO
>> Repair or replace ground connection.

2.CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT

1.
2.
3.

Disconnect refrigerant pressure sensor harness connector.

Turn ignition switch ON.
Check the voltage between refrigerant pressure sensor harness connector and ground.

Refrigerant pressure sensor

Connector

Terminal

E77

Ground

Voltage

Ground

Approx. 5V

Is the inspection result normal?

YES >> GO TO 4.
NO
>> GO TO 3.

Revision: 2007 June

EC-511

G37 Coupe

REFRIGERANT PRESSURE SENSOR

[VQ37VHR]

< COMPONENT DIAGNOSIS >

3.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

4.CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1.
2.
3.

Turn ignition switch OFF.

Disconnect ECM harness connector.
Check the continuity between refrigerant pressure sensor harness connector and ECM harness connector.

Refrigerant pressure sensor

ECM

Connector

Terminal

Connector

Terminal

E77

M107

116

Continuity
Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 6.
NO
>> GO TO 5.

5.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

6.CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.

Check the continuity between refrigerant pressure sensor harness connector and ECM harness connector.

Refrigerant pressure sensor

ECM

Connector

Terminal

Connector

Terminal

E77

M107

105

Continuity
Existed

2. Also check harness for short to ground and short to power.

Is the inspection result normal?
YES >> GO TO 8.
NO
>> GO TO 7.

7.DETECT MALFUNCTIONING PART

Check the following.
Harness connectors M6, E106
Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.

8.CHECK INTERMITTENT INCIDENT

Refer to GI-38, "Intermittent Incident".
Is the inspection result normal?
YES >> Replace refrigerant pressure sensor.
NO
>> Repair or replace.

Revision: 2007 June

EC-512

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

ECU DIAGNOSIS

ECM
Reference Value

INFOID:0000000001734347

EC

VALUES ON THE DIAGNOSIS TOOL

NOTE:
Specification data are reference values.
Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show
the specification data in spite of the ignition timing not being adjusted to the specification data. this IGN TIMING monitors the data calculated by the ECM according to the signals input from the camshaft position sensor and other ignition timing related sensors.

CONSULT-III MONITOR ITEM

Monitor Item

Condition

Values/Status
Almost the same speed as
the tachometer indication

ENG SPEED

Run engine and compare CONSULT-III value with the tachometer indication.

MAS A/F SE-B1

See EC-132, "Description".

MAS A/F SE-B2

See EC-132, "Description".

B/FUEL SCHDL

See EC-132, "Description".

A/F ALPHA-B1

See EC-132, "Description".

A/F ALPHA-B2

See EC-132, "Description".

COOLAN TEMP/S

Ignition switch: ON

A/F SEN1 (B1)

Engine: After warming up

Maintaining engine speed at 2,000 rpm

Fluctuates around 2.2 V

A/F SEN1 (B2)

Engine: After warming up

Maintaining engine speed at 2,000 rpm

Fluctuates around 2.2 V

HO2S2 (B1)

Revving engine from idle up to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- After keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

0 - 0.3V Approx. 0.6 1.0V

HO2S2 (B2)

Revving engine from idle up to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- After keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

0 - 0.3V Approx. 0.6 1.0V

HO2S2 MNTR (B1)

Revving engine from idle up to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- After keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

LEAN RICH

HO2S2 MNTR (B2)

Revving engine from idle up to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- After keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

LEAN RICH

VHCL SPEED SE

Turn drive wheels and compare CONSULT-III value with the speedometer indication.

Almost the same speed as

speedometer indication

BATTERY VOLT

Ignition switch: ON (Engine stopped)

11 - 14V

ACCEL SEN 1

Ignition switch: ON
(Engine stopped)

Accelerator pedal: Fully released

0.45 - 1.00V

Accelerator pedal: Fully depressed

4.4 - 4.8V

ACCEL SEN 2*1

Ignition switch: ON
(Engine stopped)

Accelerator pedal: Fully released

0.45 - 1.00V

Accelerator pedal: Fully depressed

4.3 - 4.8V

Revision: 2007 June

H
Indicates engine coolant
temperature

EC-513

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Monitor Item

Condition

Values/Status

Ignition switch: ON
(Engine stopped)
Selector lever: D (A/T) or 1st (M/T)

Accelerator pedal: Fully released

More than 0.36V

TP SEN 1-B1

Accelerator pedal: Fully depressed

Less than 4.75V

Ignition switch: ON
(Engine stopped)
Selector lever: D (A/T) or 1st (M/T)

Accelerator pedal: Fully released

More than 0.36V

TP SEN 2-B1*1

Accelerator pedal: Fully depressed

Less than 4.75V

FUEL T/TMP SE

Ignition switch: ON

Indicates fuel tank temperature

INT/A TEMP SE

Ignition switch: ON

Indicates intake air temperature

EVAP SYS PRES

Ignition switch: ON

Approx. 1.8 - 4.8V

FUEL LEVEL SE

Ignition switch: ON

Depending on fuel level of

fuel tank

START SIGNAL

Ignition switch: ON START ON

CLSD THL POS

Ignition switch: ON
(Engine stopped)

AIR COND SIG

Engine: After warming up, idle the

engine

P/N POSI SW

Ignition switch: ON

PW/ST SIGNAL

Engine: After warming up, idle the

engine

LOAD SIGNAL

IGNITION SW

Ignition switch: ON

OFF ON OFF
Accelerator pedal: Fully released

ON

Accelerator pedal: Slightly depressed

OFF

Air conditioner switch: OFF

OFF

Air conditioner switch: ON

(Compressor operates.)

ON

Selector lever: P or N (A/T), Neutral (M/T)

ON

Selector lever: Except above

OFF

Steering wheel: Not being turned

OFF

Steering wheel: Being turned

ON

Rear window defogger switch: ON

and/or
Lighting switch: 2nd position

ON

Rear window defogger switch and lighting

switch: OFF

OFF

Heater fan switch: ON

ON

Heater fan switch: OFF

OFF

Ignition switch: ON OFF ON

ON OFF ON

HEATER FAN SW

Engine: After warming up, idle the

engine

BOOST VCUM SW

Always a certain value is displayed.

This items are not efficient for CV36 models.

BRAKE SW

Ignition switch: ON

INJ PULSE-B1

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,000 rpm

1.9 - 2.9 msec

Idle

2.0 - 3.0 msec

INJ PULSE-B2

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,000 rpm

1.9 - 2.9 msec

Idle

7 BTDC

IGN TIMING

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,000 rpm

25 - 45 BTDC

Revision: 2007 June

Brake pedal: Fully released

OFF

Brake pedal: Slightly depressed

ON

Idle

2.0 - 3.0 msec

EC-514

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Monitor Item

Condition

Values/Status

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

Idle

5% - 35%

2,500 rpm

5% - 35%

Idle

2.0 - 6.0 gm/s

MASS AIRFLOW

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,500 rpm

7.0 - 20.0 gm/s

Idle
(Accelerator pedal: Not depressed even
slightly, after engine starting.)

0%

PURG VOL C/V

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,000 rpm

Idle

0% - 2%

INT/V SOL (B1)

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,000 rpm

Approx. 0% - 50%

Idle

0% - 2%

INT/V SOL (B2)

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

2,000 rpm

Approx. 0% - 50%

Ignition switch: ON
(Engine stopped)
Selector lever: D (A/T) or 1st (M/T)

Accelerator pedal: Fully released

More than 0.36V

TP SEN 1-B2

Accelerator pedal: Fully depressed

Less than 4.75V

Accelerator pedal: Fully released

More than 0.36V

TP SEN 2-B2*1

Ignition switch: ON
(Engine stopped)
Selector lever: D (A/T) or 1st (M/T)

Accelerator pedal: Fully depressed

Less than 4.75V

Air conditioner switch: OFF

OFF

Air conditioner switch: ON

(Compressor operates)

ON

CAL/LD VALUE

AIR COND RLY

Engine: After warming up, idle the

engine

Except above

OFF

VENT CONT/V

Ignition switch: ON

OFF

THRTL RELAY

Ignition switch: ON

ON

Engine speed: Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

ON

Engine speed: Above 3,600 rpm

OFF

Engine speed: Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

ON

Engine speed: Above 3,600 rpm

OFF

I/P PULLY SPD

Vehicle speed: More than 20 km/h (12 MPH)

Almost the same speed as

the tachometer indication

VEHICLE SPEED

Turn drive wheels and compare CONSULT-III value with the speedometer indication.

Almost the same speed as

the speedometer indication

HO2S2 HTR (B2)

Revision: 2007 June

ON

HO2S2 HTR (B1)

For 1 seconds after turning ignition switch: ON

Engine running or cranking

FUEL PUMP RLY

EC

EC-515

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Monitor Item

IDL A/V LEARN

Condition

Engine: Running

Values/Status

Idle air volume learning has not been performed yet.

YET

Idle air volume learning has already been

performed successfully.

CMPLT

ENG OIL TEMP

Engine: After warming up

TRVL AFTER MIL

Ignition switch: ON

A/F S1 HTR (B1)

Engine: After warming up, idle the engine

(More than 140 seconds after starting engine)

4 - 100%

A/F S1 HTR (B2)

Engine: After warming up, idle the engine

(More than 140 seconds after starting engine)

4 - 100%

AC PRESS SEN

Engine: Idle
Both A/C switch and blower fan switch: ON (Compressor operates)

1.0 - 4.0V

VHCL SPEED SE

Turn drive wheels and compare CONSULT-III value with the speedometer indication.

Almost the same speed as

the speedometer indication

SET VHCL SPD

Engine: Running

ASCD: Operating

The preset vehicle speed is

displayed

MAIN SW

Ignition switch: ON

MAIN switch: Pressed

ON

MAIN switch: Released

OFF

CANCEL switch: Pressed

ON

CANCEL switch: Released

OFF

RESUME/ACCELERATE switch:
Pressed

ON

RESUME/ACCELERATE switch: Released

OFF

SET/COAST switch: Pressed

ON

SET/COAST switch: Released

OFF

Brake pedal: Fully released

ON

Brake pedal: Slightly depressed

OFF

Brake pedal: Fully released

OFF

Brake pedal: Slightly depressed

ON

DISTANCE switch: Pressed

ON

DISTANCE switch: Released

OFF

CANCEL SW

RESUME/ACC SW

Ignition switch: ON

Ignition switch: ON

SET SW

Ignition switch: ON

BRAKE SW1
(ICC/ASCD brake
switch)

Ignition switch: ON

BRAKE SW2
(Stop lamp switch)

Ignition switch: ON

DIST SW

Ignition switch: ON

More than 70C (158F)

Vehicle has traveled after MIL has turned
ON.

0 - 65,535 km
(0 - 40,723 miles)

VHCL SPD CUT

Ignition switch: ON

NON

LO SPEED CUT

Ignition switch: ON

NON

AT OD MONITOR

Ignition switch: ON

OFF

AT OD CANCEL

Ignition switch: ON

OFF

CRUISE LAMP

Ignition switch: ON

SET LAMP

MAIN switch: ON
When vehicle speed is between 40
km/h (25 MPH) and 144 km/h (89
MPH)

MAIN switch: Pressed at the 1st time

at the 2nd time

ON OFF

ASCD: Operating

ON

ASCD: Not operating

OFF

Engine speed: Idle

BAT CUR SEN

ALT DUTY

Revision: 2007 June

Battery: Fully charged*2

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

Engine: Idle

Approx. 2,600 - 3,500mV

0 - 80%

EC-516

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Monitor Item

Condition

Values/Status

Idle

Approx. 0.25 - 1.40V

VVEL POSITION
SEN-B1

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

When revving engine up to 2,000 rpm

quickly

Approx. 0.25 - 4.75V

Idle

Approx. 0.25 - 1.40V

VVEL POSITION
SEN-B2

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

When revving engine up to 2,000 rpm

quickly

Approx. 0.25 - 4.75V

Idle

Approx. 0 - 20 deg

VVEL TIM-B1

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

When revving engine up to 2,000 rpm

quickly

Approx. 0 - 90 deg

Engine: After warming up

Selector lever: P or N (A/T), Neutral (M/T)
Air conditioner switch: OFF
No load

Idle

Approx. 0 - 20 deg

When revving engine up to 2,000 rpm

quickly

Approx. 0 - 90 deg

VVEL learning has not been performed

yet.

YET

VVEL learning has already been performed successfully.

DONE

VVEL TIM-B2

VVEL LEARN

Ignition switch: OFF ON

(After warming up)

EC

VVEL SEN LEARNB1

VVEL learning has already been performed successfuly

Approx. 0.30 - 0.80V

VVEL SEN LEARNB2

VVEL learning has already been performed successfuly

Approx. 0.30 - 0.80V

ALT DUTY

Engine: Idle

0 - 80%

A/F ADJ B1

Engine: Running

0.330 - 0.330

A/F ADJ B2

Engine: Running

0.330 - 0.330

FAN DUTY

Engine: Running

0 - 100%

Power generation voltage variable control: Operating

ON

Power generation voltage variable control: Not operating

OFF

ALT DUTY SIG

*1: Accelerator pedal position sensor 2 signal and throttle position sensor 2 signal are converted by ECM internally. Thus, they differ
from ECM terminals voltage signal.

*2: Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to PG-3, "How to Handle Battery".

TERMINAL LAYOUT

JMBIA0070ZZ

PHYSICAL VALUES
NOTE:
ECM is located behind the instrument assist lower panel. For this inspection, remove passenger side instrument lower panel.
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-III.
Revision: 2007 June

EC-517

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

Description

Signal name

Value
(Approx.)

Condition

Input/
Output

2.9 - 8.8V

1
(W)

128
(B)

A/F sensor 1 heater

(bank 1)

Output

[Engine is running]
Warm-up condition
Idle speed
(More than 140 seconds after starting
engine)
JMBIA0030GB

0 - 14V
[Ignition switch: ON]
Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully depressed
2
(G)

128
(B)

Throttle control motor

(Open) (bank 1)

JMBIA0031GB

Output
0 - 14V
[Ignition switch: ON]
Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully released
JMBIA0032GB

3
(R)

128
(B)

Throttle control motor relay power supply (bank

1)

Input

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)
0 - 14V

4
(BR)

128
(B)

Throttle control motor

(Close) (bank 1)

Output

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: In the middle of releasing operation
JMBIA0033GB

2.9 - 8.8V

5
(GR)

128
(B)

A/F sensor 1 heater

(bank 2)

Output

[Engine is running]
Warm-up condition
Idle speed
(More than 140 seconds after starting
engine)
JMBIA0030GB

8
(B)

ECM ground

Revision: 2007 June

EC-518

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

Description

Signal name

11
(GR)

Ignition signal No. 4

12
(L)

Ignition signal No. 3

15
(V)

Ignition signal No. 5

16
(G)

128
(B)

Input/
Output

Value
(Approx.)

Condition

EC

0 - 0.2V
[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on
rpm at idle

JMBIA0035GB

Output
0.1 - 0.4V

Ignition signal No. 2

19
(SB)

Ignition signal No. 6

20
(Y)

Ignition signal No. 1

[Engine is running]
Warm-up condition
Engine speed: 2,000 rpm

F
JMBIA0036GB

17
(P)

128
(B)

Heated oxygen sensor 2

heater (bank 1)

Output

[Engine is running]
Engine speed: Below 3,600 rpm after
the following conditions are met
- Engine: after warming up
- Keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

10V

JMBIA0037GB

[Ignition switch: ON]

Engine stopped
[Engine is running]
Engine speed: Above 3,600 rpm

BATTERY VOLTAGE
(11 - 14V)

[Engine is running]
Warm-up condition
Idle speed

BATTERY VOLTAGE
(11 - 14V)

7 - 12V
18
(W)

128
(B)

Intake valve timing control solenoid valve (bank

1)

Output

L
[Engine is running]
Warm-up condition
Engine speed: 2,000rpm

M
JMBIA0038GB

Revision: 2007 June

EC-519

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

Description

Signal name

Input/
Output

Value
(Approx.)

Condition

BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Idle speed
Accelerator pedal: Not depressed even
slightly, after engine starting

21
(GR)

128
(B)

EVAP canister purge volume control solenoid

valve

JMBIA0039GB

Output

BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Engine speed: About 2,000 rpm (More
than 100 seconds after starting engine)

JMBIA0040GB

22
(R)

24
(P)

25
(O)

28
(BR)

128
(B)

128
(B)

128
(B)

128
(B)

Fuel pump relay

ECM relay
(Self shut-off)

Throttle control motor relay

VVEL actuator motor relay abort signal

[VVEL control module]

Output

Output

Output

Output

[Ignition switch: ON]

For 1 second after turning ignition switch
ON
[Engine is running]

0 - 1.5V

[Ignition switch: ON]

More than 1 second after turning ignition
switch ON

BATTERY VOLTAGE
(11 - 14V)

[Engine is running]
[Ignition switch: OFF]
A few seconds after turning ignition
switch OFF

0 - 1.5V

[Ignition switch: OFF]

More than a few seconds after turning
ignition switch OFF

BATTERY VOLTAGE
(11 - 14V)

[Ignition switch: ON OFF]

0 - 1.0V

BATTERY VOLTAGE
(11 - 14V)

0V

[Ignition switch: ON]

0 - 1.0V

[Engine is running]
Warm-up condition
Idle speed

0V

[Engine is running]
Warm-up condition
Idle speed

BATTERY VOLTAGE
(11 - 14V)
7 - 12V

29
(G)

128
(B)

Intake valve timing control solenoid valve (bank

2)

Output

[Engine is running]
Warm-up condition
Engine speed: 2,000rpm

JMBIA0038GB

Revision: 2007 June

EC-520

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

30
(Y)

31
(R)

33
(SB)

Description

40
(R)

48
(B)

128
(B)

Signal name

Throttle position sensor

1 (bank 1)

Throttle position sensor

1 (bank 2)

Heated oxygen sensor 2

heater (bank 2)

Input/
Output

Input

Input

Output

EC

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully released

More than 0.36V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully depressed

Less than 4.75V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully released

More than 0.36V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully depressed

Less than 4.75V

[Engine is running]
Engine speed: Below 3,600 rpm after
the following conditions are met
- Engine: after warming up
- Keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

Value
(Approx.)

Condition

10V

JMBIA0037GB

34
(B)

35
(W)

36
(O)

40
(R)

48
(B)

Throttle position sensor

2 (bank 1)

Throttle position sensor

2 (bank 2)

Sensor ground
[Brake booster pressure
sensor]

Input

Input

[Ignition switch: ON]

Engine stopped
[Engine is running]
Engine speed: Above 3,600 rpm

BATTERY VOLTAGE
(11 - 14V)

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully released

Less than 4.75V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully depressed

More than 0.36V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully released

Less than 4.75V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully depressed

More than 0.36V

Revision: 2007 June

EC-521

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

Description

Signal name

Value
(Approx.)

Condition

Input/
Output

4.0 - 5.0
[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on
rpm at idle
37
(W)

128
(B)

Crankshaft position sensor (POS)

JMBIA0041GB

Input
4.0 - 5.0

[Engine is running]
Engine speed: 2,000 rpm

JMBIA0042GB

38
(O)

39
(P)

96
(P)

36
(O)

Manifold absolute pressure (MAP) sensor

Brake booster pressure

sensor

Input

Input

[Engine is running]
Warm-up condition
Idle speed

1.2V

[Engine is running]
Warm-up condition
Engine speed: 2,000 rpm

1.5V

[Engine is running]
Warm-up condition
Idle speed
Brake pedal: Fully released

1.2V

[Engine is running]
Warm-up condition
Idle speed
Brake pedal: Fully depressed

3.0V

40
(R)

Sensor ground
[Throttle position sensor
(bank 1)]

43
(G)

48
(B)

Sensor power supply

[Throttle position sensor
(bank 2)]

[Ignition switch: ON]

5V

44
(L)

40
(R)

Sensor power supply

[Throttle position sensor
(bank 1)]

[Ignition switch: ON]

5V

45
(LG)

36
(O)

Sensor power supply

[Brake booster pressure
sensor]

[Ignition switch: ON]

5V

46
(R)

128
(B)

Sensor power supply

[Crankshaft position
sensor (POS)]

[Ignition switch: ON]

5V

47
(Y)

Sensor ground
[Crankshaft position
sensor (POS)]

48
(B)

Sensor ground
[Throttle position sensor
(bank 2)]

Revision: 2007 June

EC-522

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

Description

Signal name

Input/
Output

Value
(Approx.)

Condition

EC

0 - 14V

49
(GR)

128
(B)

Throttle control motor

(Close) (bank 2)

Output

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: In the middle of releasing operation

JMBIA0033GB

0 - 14V

[Ignition switch: ON]

Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully depressed
50
(V)

128
(B)

Throttle control motor

(Open) (bank 2)

F
JMBIA0031GB

Output

0 - 14V
[Ignition switch: ON]
Engine stopped
Selector lever: D (A/T) or 1st (M/T)
Accelerator pedal: Fully released

JMBIA0032GB

52
(R)

128
(B)

Throttle control motor relay power supply (bank

2)

Input

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

[Ignition switch: OFF]

0V

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

53
(W)

128
(B)

54
(Y)

CAN communication line

[VVEL control module]

Input/
output

55
(LG)

CAN communication line

[VVEL control module]

Input/
output

57
(L)

128
(B)

A/F sensor 1 (bank 1)

Input

[Ignition switch: ON]

2.2V

Ignition switch

Input

3.0 - 5.0
[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on
rpm at idle
59
(O)

128
(B)

Camshaft position sensor (PHASE) (bank 1)

O
JMBIA0045GB

Input
3.0 - 5.0

[Engine is running]
Engine speed: 2,000 rpm

JMBIA0046GB

Revision: 2007 June

EC-523

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)

Description

Signal name

Input/
Output

60
(G)

128
(B)

Sensor power supply

[Camshaft position sensor (PHASE) (bank 1),
Manifold absolute pressure (MAP) sensor, Power steering pressure
sensor]

61
(R)

128
(B)

A/F sensor 1 (bank 1)

Input

Value
(Approx.)

Condition

[Ignition switch: ON]

5V

[Engine is running]
Warm-up condition
Engine speed: 2,000 rpm

1.8V
Output voltage varies with air fuel
ratio.
3.0 - 5.0

[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on
rpm at idle
63
(L)

128
(B)

Camshaft position sensor (PHASE) (bank 2)

JMBIA0045GB

Input
3.0 - 5.0

[Engine is running]
Engine speed: 2,000 rpm

JMBIA0046GB

64
(SB)

128
(B)

Sensor power supply

[Camshaft position sensor (PHASE) (bank 2),
Battery current sensor]

65
(LG)

128
(B)

66
(V)
67
(P)

[Ignition switch: ON]

5V

A/F sensor 1 (bank 2)

Input

[Ignition switch: ON]

2.2V

128
(B)

A/F sensor 1 (bank 2)

Input

[Engine is running]
Warm-up condition
Engine speed: 2,000 rpm

1.8V
Output voltage varies with air fuel
ratio.

128
(B)

Intake air temperature

sensor (bank 1)

Input

[Engine is running]

0 - 4.8V
Output voltage varies with intake
air temperature.

Sensor ground
[Mass air flow sensor
(bank 1), Intake air temperature sensor (bank
1)]

68
(LG)

69
(W)

128
(B)

Knock sensor (bank 2)

Input

[Engine is running]
Idle speed

2.5V*1

71
(Y)

128
(B)

Engine coolant temperature sensor

Input

[Engine is running]

0 - 4.8V
Output voltage varies with engine
coolant temperature.

72
()

73
(W)

128
(B)

[Engine is running]
Idle speed

2.5V*1

Sensor ground
(Knock sensor)
Knock sensor (bank 1)

Revision: 2007 June

Input

EC-524

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

76
(W)

77
(SB)

78
(G)

79
(BR)

80
(O)

Description

128
(B)

68
(LG)

84
(B)

94
(Y)

128
(B)

81
(R)

Signal name

Heated oxygen sensor 2

(bank 1)

Mass air flow sensor

(bank 1)

Engine oil temperature

sensor

Mass air flow sensor

(bank 2)

Heated oxygen sensor 2

(bank 2)

Input

Input

Input

Input

Input

Fuel injector No. 6

85
(BR)

Fuel injector No. 2

128
(B)

EC

[Engine is running]
Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met
- Engine: after warming up
- Keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

0 - 1.0V

[Engine is running]
Warm-up condition
Idle speed

0.7 - 1.2V

[Engine is running]
Warm-up condition
Engine speed: 2,500 rpm

1.3 - 1.7V

[Engine is running]

0 - 4.8V
Output voltage varies with engine
oil temperature.

[Engine is running]
Warm-up condition
Idle speed

0.7 - 1.2V

[Engine is running]
Warm-up condition
Engine speed: 2,500 rpm

1.3 - 1.7V

[Engine is running]
Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met
- Engine: after warming up
- Keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load

[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on
rpm at idle

I
0 - 1.0V

(11 - 14V)

M
JMBIA0047GB

Output

BATTERY VOLTAGE

Fuel injector No. 5

(11 - 14V)

89
(GR)

Fuel injector No. 1

90
(O)

[Engine is running]
Warm-up condition
Engine speed: 2,000 rpm

Fuel injector No. 4

P
JMBIA0048GB

83
(LG)

BATTERY VOLTAGE

Fuel injector No. 3

82
(V)

86
(W)

Input/
Output

Value
(Approx.)

Condition

94
(Y)

Intake air temperature

sensor (bank 2)

Revision: 2007 June

Input

[Engine is running]

EC-525

0 - 4.8V
Output voltage varies with intake
air temperature.

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

84
(B)

Description

Signal name

Input/
Output

Sensor ground
(Heated oxygen sensor
2, Engine coolant temperature sensor, Engine
oil temperature sensor)

87
(Y)

96
(P)

Power steering pressure

sensor

91
(SB)

95
(G)

Battery current sensor

92
(G)

Sensor ground
[Camshaft position sensor (PHASE) (bank 2)]

93
(P)

128
(B)

Power supply for ECM

(Back-up)

Input

94
(Y)

Sensor ground
[Mass air flow sensor
(bank 2)]

95
(G)

96
(P)

97
(R)

98
(P)

100
(W)

104
(GR)

Output

Value
(Approx.)

Condition

[Engine is running]
Steering wheel: Being turned

0.5 - 4.5V

[Engine is running]
Steering wheel: Not being turned

0.4 - 0.8V

[Engine is running]
Battery: Fully charged*2
Idle speed

2.6 - 3.5V

[Ignition switch: OFF]

BATTERY VOLTAGE
(11 - 14V)

Sensor ground
(Battery current sensor)

Sensor ground
[Camshaft position sensor (PHASE) (bank
1),Manifold absolute
pressure (MAP) sensor,
Power steering pressure
sensor]

[Ignition switch: ON]

Engine stopped
Accelerator pedal: Fully released

0.45 - 1.00V

[Ignition switch: ON]

Engine stopped
Accelerator pedal: Fully depressed

4.2 - 4.8V

[Ignition switch: ON]

Engine stopped
Accelerator pedal: Fully released

0.22 - 0.50V

[Ignition switch: ON]

Engine stopped
Accelerator pedal: Fully depressed

2.1 - 2.5V

Accelerator pedal position sensor 1

Accelerator pedal position sensor 2

Input

Input

Input

99
(L)

100
(W)

Sensor power supply

(Accelerator pedal position sensor 1)

[Ignition switch: ON]

5V

100
(W)

Sensor ground
(Accelerator pedal position sensor 1)

Revision: 2007 June

EC-526

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

101
(SB)

101
(SB)

Description

108
(Y)

108
(Y)

Signal name

ICC steering switch

(models with ICC system)

ASCD steering switch

(models with ASCD system)

Input/
Output

[Ignition switch: ON]

ICC steering switch: OFF

4.3V

[Ignition switch: ON]

MAIN switch: Pressed

0V

[Ignition switch: ON]

CANCEL switch: Pressed

1.3V

[Ignition switch: ON]

RESUME/ACCELERATE switch:
Pressed

3.7V

[Ignition switch: ON]

SET/COAST switch: Pressed

3V

[Ignition switch: ON]

DISTANCE switch: Pressed

2.2V

[Ignition switch: ON]

ASCD steering switch: OFF

4V

[Ignition switch: ON]

MAIN switch: Pressed

0V

[Ignition switch: ON]

CANCEL switch: Pressed

1V

[Ignition switch: ON]

RESUME/ACCELERATE switch:
Pressed

3V

[Ignition switch: ON]

SET/COAST switch: Pressed

2V

Input

[Ignition switch: ON]

1.8 - 4.8V

[Ignition switch: ON]

5V

Input

Input

102
(GR)

112
(SB)

EVAP control system

pressure sensor

103
(G)

104
(GR)

Sensor power supply

(Accelerator pedal position sensor 2)

Sensor ground
(Accelerator pedal position sensor 2)

104
(GR)

Refrigerant pressure
sensor

Input

106
(W)

128
(B)

Fuel tank temperature

sensor

Input

112
(SB)

Sensor power supply

(EVAP control system
pressure sensor)

Sensor ground
(ASCD/ICC steering
switch)

109
(G)

128
(B)

PNP switch

Revision: 2007 June

EC

116
(P)

108
(Y)

105
(L)

107
(BR)

Value
(Approx.)

Condition

[Engine is running]
Warm-up condition
Both A/C switch and blower fan motor
switch: ON (Compressor operates)

1.0 - 4.0V

[Engine is running]

0 - 4.8V
Output voltage varies with fuel
tank temperature.

[Ignition switch: ON]

5V

Input

[Ignition switch: ON]

Selector lever: P or N (A/T), Neutral (M/
T)

BATTERY VOLTAGE
(11 - 14V)

[Ignition switch: ON]

Selector lever: Except above

0V

EC-527

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
(Wire color)
+

Description

Signal name

Value
(Approx.)

Condition

Input/
Output

1V
[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on
rpm at idle
110
(R)

128
(B)

Engine speed output signal

JMBIA0076GB

Output
1V

[Engine is running]
Engine speed is 2,000 rpm

JMBIA0077GB

111
(O)

116
(P)

Sensor power supply

(Refrigerant pressure
sensor)

[Ignition switch: ON]

5V

112
(SB)

Sensor ground
(EVAP control system
pressure sensor)

113
(P)

CAN communication line

Input/
Output

114
(L)

CAN communication line

Input/
Output

116
(P)

Sensor ground
(Refrigerant pressure
sensor)

117
(V)

128
(B)

Data link connector

Input/
Output

[Ignition switch: ON]

GST: Disconnected

5V - BATTERY VOLTAGE (11 14V)

121
(LG)

128
(B)

EVAP canister vent control valve

Output

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

122
(P)

128
(B)

[Ignition switch: OFF]

Brake pedal: Fully released

0V

[Ignition switch: OFF]

Brake pedal: Slightly depressed

BATTERY VOLTAGE
(11 - 14V)

123
(B)
124
(B)

125
(R)

128
(B)

Power supply for ECM

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

128
(B)

[Ignition switch: ON]

Brake pedal: Slightly depressed

0V

126
(BR)

ICC brake switch (models with ICC system)

ASCD brake switch
(models with ASCD system)

[Ignition switch: ON]

Brake pedal: Fully released

BATTERY VOLTAGE
(11 - 14V)

127
(B)
128
(B)

Stop lamp switch

ECM ground

ECM ground

Input

Input

Input

: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)

Revision: 2007 June

EC-528

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

*1: This may vary depending on internal resistance of the tester.

**2: Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to PG-3, "How to Handle Battery".

Wiring Diagram - ENGINE CONTROL SYSTEM -

INFOID:0000000001734348

EC

Click here to view the eWD.

JCBWA0348GB

Revision: 2007 June

EC-529

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0349GB

Revision: 2007 June

EC-530

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0350GB

Revision: 2007 June

EC-531

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0351GB

Revision: 2007 June

EC-532

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0352GB

Revision: 2007 June

EC-533

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0353GB

Revision: 2007 June

EC-534

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0354GB

Revision: 2007 June

EC-535

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0355GB

Revision: 2007 June

EC-536

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0356GB

Revision: 2007 June

EC-537

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0357GB

Revision: 2007 June

EC-538

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0358GB

Revision: 2007 June

EC-539

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0359GB

Revision: 2007 June

EC-540

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0360GB

Revision: 2007 June

EC-541

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0361GB

Revision: 2007 June

EC-542

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0362GB

Revision: 2007 June

EC-543

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0363GB

Revision: 2007 June

EC-544

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0364GB

Revision: 2007 June

EC-545

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0365GB

Revision: 2007 June

EC-546

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0366GB

Revision: 2007 June

EC-547

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0367GB

Fail Safe

INFOID:0000000001734349

NON DTC RELATED ITEM

Revision: 2007 June

EC-548

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Engine operating condition in fail-safe mode
Engine speed will not
rise more than 2,500 rpm
due to the fuel cut

Reference
page

Detected items

Remarks

Malfunction indicator
lamp circuit

When there is an open circuit on MIL circuit, the ECM cannot warn the
driver by lighting up MIL when there is malfunction on engine control
system.
Therefore, when electrical controlled throttle and part of ECM related
diagnoses are continuously detected as NG for 5 trips, ECM warns the
driver that engine control system malfunctions and MIL circuit is open
by means of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL
circuit are detected and demands the driver to repair the malfunction.

EC
EC-503

DTC RELATED ITEM

DTC No.

Detected items

Engine operating condition in fail-safe mode

U0113
U1003
U1011
U1024

Can communication circuit

P0011
P0021

Intake valve timing control

The signal is not energized to the intake valve timing control solenoid valve and the valve
control does not function.

P0102
P0103
P010C
P010D

Mass air flow sensor circuit

Engine speed will not rise more than 2,400 rpm due to the fuel cut.

P0117
P0118

Engine coolant temperature sensor circuit

Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-III displays the engine coolant temperature decided by ECM.

VVEL actuator motor relay is turned off, and VVEL value is become at a minimam angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.

Condition

Engine coolant temperature decided

(CONSULT-III display)

Just as ignition switch is turned ON

or START

40C (104F)

Approx 4 minutes or more after engine starting

80C (176F)

Except as shown above

40 - 80C (104 - 176F)

(Depends on the time)

When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P0227
P0228
P1239
P2132
P2133
P2135

Throttle position sensor

The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.

P0500

Vehicle speed sensor

P0524

Engine oil pressure

P0605

ECM

(When ECM calculation function is malfunctioning:)

ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
ECM deactivates ASCD operation.

P0643

Sensor power supply

ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.

Revision: 2007 June

When the fail-safe system for vehicle speed sensor is activated, the cooling fan operates
(Highest) while engine is running.
The signal is not energized to the intake valve timing control solenoid valve and the valve
control does not function.
Engine speed will not rise more than 2,400 rpm due to the fuel cut.

EC-549

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DTC No.

Detected items

Engine operating condition in fail-safe mode

P1087
P1088

VVEL control function

VVEL of normal bank is controlled at VVEL angle of abnormal bank.

Engine speed will not rise more than 3,500 rpm due to the fuel cut.

P1089
P1092
P1608

VVEL control shaft position

sensor

P1608

VVEL control shaft position

sensor

VVEL actuator motor relay is turned off, and VVEL value is become at a minimam angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut

P1090
P1093

VVEL actuator motor

VVEL of normal bank is controlled at VVEL angle of abnormal bank.

Engine speed will not rise more than 3,500 rpm due to the fuel cut.

VVEL value is maintained at a fixed angle.

Engine speed will not rise more than 3,500 rpm due to the fuel cut

VVEL actuator motor relay is turned off, and VVEL value is become at a minimam angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P1091

VVEL actuator motor relay

VVEL actuator motor relay is turned off, and VVEL value is become at a minimam angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.

P1233
P2101

Electric throttle control

function

ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.

P1236
P2118

Throttle control motor

ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.

P1238
P2119

Electric throttle control actuator

(When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the
engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or
more.

P1290
P2100
P2103

Throttle control motor relay

P1606

VVEL control module

VVEL actuator motor relay is turned off, and VVEL value is become at a minimam angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.

P1805

Brake switch

ECM controls the electric throttle control actuator by regulating the throttle opening to a
small range.
Therefore, acceleration will be poor.

ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.

Vehicle condition

P2122
P2123
P2127
P2128
P2138

Accelerator pedal position

sensor

Driving condition

When engine is idling

Normal

When accelerating

Poor acceleration

The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.

DTC Inspection Priority Chart

INFOID:0000000001734350

If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.

Revision: 2007 June

EC-550

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Priority
1

Detected items (DTC)

U0113 U1003 CAN communication line

U1000 U1001 CAN communication line
U1010 CAN communication
U1011 CAN communication
U1024 VVEL CAN communication line
P0101 P0102 P0103 P010B P010C P010D Mass air flow sensor
P010A Manifold absolute pressure (MAP) sensor
P0112 P0113 P0127 Intake air temperature sensor
P0117 P0118 P0125 Engine coolant temperature sensor
P0122 P0123 P0222 P0223 P0227 P0228 P1225 P1226 P1234 P1235 P1239 P2132 P2133 P2135 Throttle position sensor
P0128 Thermostat function
P0181 P0182 P0183 Fuel tank temperature sensor
P0196 P0197 P0198 Engine oil temperature sensor
P0327 P0328 P0332 P0333 Knock sensor
P0335 Crankshaft position sensor (POS)
P0340 P0345 Camshaft position sensor (PHASE)
P0460 P0461 P0462 P0463 Fuel level sensor
P0500 Vehicle speed sensor
P0555 Brake booster pressure sensor
P0605 ECM
P0643 Sensor power supply
P0700 TCM
P0705 P0850 Park/neutral position (PNP) switch
P1089 P1092 P1608 VVEL control shaft position sensor
P1606 P1607 VVEL control module
P0705 P0850 Park/neutral position (PNP) switch
P1550 P1551 P1552 P1553 P1554 Battery current sensor
P1610 - P1615 NATS
P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor

EC

Revision: 2007 June

EC-551

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Priority
2

Detected items (DTC)

P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater
P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
P0075 P0081 Intake valve timing control solenoid valve
P0130 P0131 P0132 P0133 P0150 P0151 P0152 P0153 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
P0441 EVAP control system purge flow monitoring
P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
P0447 P0448 EVAP canister vent control valve
P0451 P0452 P0453 EVAP control system pressure sensor
P0550 Power steering pressure sensor
P0603 ECM power supply
P0710 P0717 P0720 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P1730 P1752 P1757 P1762 P1767 P1772
P1774 A/T related sensors, solenoid valves and switches
P1087 P1088 VVEL system
P1090 P1093 VVEL actuator motor
P1091 VVEL actuator motor relay
P1217 Engine over temperature (OVERHEAT)
P1233 P2101 Electric throttle control function
P1236 P2118 Throttle control motor
P1290 P2100 P2103 Throttle control motor relay
P1805 Brake switch

P0011 P0021 Intake valve timing control

P0171 P0172 P0174 P0175 Fuel injection system function
P0300 - P0306 Misfire
P0420 P0430 Three way catalyst function
P0442 P0456 EVAP control system (SMALL LEAK, VERY SMALL LEAK)
P0455 EVAP control system (GROSS LEAK)
P0506 P0507 Idle speed control system
P0524 Engine oil pressure
P100A P100B VVEL system
P1148 P1168 Closed loop control
P1211 TCS control unit
P1212 TCS communication line
P1238 P2119 Electric throttle control actuator
P1421 Cold start control
P1564 ICC steering switch / ASCD steering switch
P1568 ICC command value
P1572 ICC brake switch / ASCD brake switch
P1574 ICC vehicle speed sensor / ASCD vehicle speed sensor
P1715 Turbine revolution sensor

DTC Index

INFOID:0000000001734351

:Applicable : Not applicable

DTC*1
CONSULT-III
GST*2

ECM*3

Items
(CONSULT-III screen terms)

SRT code

Trip

MIL

Reference
page

U0113

0113

CAN COMM CIRCUIT

1 (A/T models)
2 (M/T models)

(A/T models)
(M/T models)

EC-144

U1000

1000*4

CAN COMM CIRCUIT

1 (A/T models)
2 (M/T models)

(A/T models)
(M/T models)

EC-146

U1001

1001*4

CAN COMM CIRCUIT

1 (with ASCD)
1 or 2 (with ICC)

EC-146

U1003

1003

CAN COMM CIRCUIT

EC-144

(A/T models)
(M/T models)

EC-147

U1010

1010

CONTROL UNIT(CAN)

1 (A/T models)
2 (M/T models)

U1011

1011

CONTROL UNIT (CAN)

1 (A/T models)
2 (M/T models)

(A/T models)
(M/T models)

EC-148

U1024

1024

VVEL CAN COMM CIRCUIT

EC-149

Revision: 2007 June

EC-552

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DTC*1
CONSULT-III
GST*2

ECM*3

Items
(CONSULT-III screen terms)

SRT code

Trip

MIL

Reference
page

P0000

0000

NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED.

Flashing*7

P0011

0011

INT/V TIM CONT-B1

EC-151

P0021

0021

INT/V TIM CONT-B2

EC-151

P0031

0031

A/F SEN1 HTR (B1)

EC-155

P0032

0032

A/F SEN1 HTR (B1)

EC-155

P0037

0037

HO2S2 HTR (B1)

EC-158

P0038

0038

HO2S2 HTR (B1)

EC-158

P0051

0051

A/F SEN1 HTR (B2)

EC-155

P0052

0052

A/F SEN1 HTR (B2)

EC-155

P0057

0057

HO2S2 HTR (B2)

EC-158

P0058

0058

HO2S2 HTR (B2)

EC-158

P0075

0075

INT/V TIM V/CIR-B1

EC-162

P0081

0081

INT/V TIM V/CIR-B2

EC-162

P0101

0101

MAF SEN/CIRCUIT-B1

EC-165

P0102

0102

MAF SEN/CIRCUIT-B1

EC-172

P0103

0103

MAF SEN/CIRCUIT-B1

EC-172

P010A

010A

ABSL PRES SEN/CIRC

EC-177

P010B

010B

MAF SEN/CIRCUIT-B2

EC-165

P010C

010C

MAF SEN/CIRCUIT-B2

EC-172

P010D

010D

MAF SEN/CIRCUIT-B2

EC-172

P0112

0112

IAT SEN/CIRCUIT-B1

EC-181

P0113

0113

IAT SEN/CIRCUIT-B1

EC-181

P0117

0117

ECT SEN/CIRC

EC-184

P0118

0118

ECT SEN/CIRC

EC-184

P0122

0122

TP SEN 2/CIRC-B1

EC-187

P0123

0123

TP SEN 2/CIRC-B1

EC-187

P0125

0125

ECT SENSOR

EC-190

P0127

0127

IAT SENSOR-B1

EC-193

P0128

0128

THERMSTAT FNCTN

EC-195

P0130

0130

A/F SENSOR1 (B1)

EC-197

P0131

0131

A/F SENSOR1 (B1)

EC-201

P0132

0132

A/F SENSOR1 (B1)

EC-204

P0133

0133

A/F SENSOR1 (B1)

EC-207

P0137

0137

HO2S2 (B1)

EC-212

P0138

0138

HO2S2 (B1)

EC-218

P0139

0139

HO2S2 (B1)

EC-226

P0150

0150

A/F SENSOR1 (B2)

EC-197

P0151

0151

A/F SENSOR1 (B2)

EC-201

P0152

0152

A/F SENSOR1 (B2)

EC-204

P0153

0153

A/F SENSOR1 (B2)

EC-207

P0157

0157

HO2S2 (B2)

EC-212

Revision: 2007 June

EC-553

G37 Coupe

EC

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DTC*1
CONSULT-III
GST*2

ECM*3

Items
(CONSULT-III screen terms)

SRT code

Trip

MIL

Reference
page

P0158

0158

HO2S2 (B2)

EC-218

P0159

0159

HO2S2 (B2)

EC-226

P0171

0171

FUEL SYS-LEAN-B1

EC-232

P0172

0172

FUEL SYS-RICH-B1

EC-236

P0174

0174

FUEL SYS-LEAN-B2

EC-232

P0175

0175

FUEL SYS-RICH-B2

EC-236

P0181

0181

FTT SENSOR

EC-240

P0182

0182

FTT SEN/CIRCUIT

EC-243

P0183

0183

FTT SEN/CIRCUIT

EC-243

P0196

0196

EOT SENSOR

EC-246

P0197

0197

EOT SEN/CIRC

EC-249

P0198

0198

EOT SEN/CIRC

EC-249

P0222

0222

TP SEN 1/CIRC-B1

EC-252

P0223

0223

TP SEN 1/CIRC-B1

EC-252

P0227

0227

TP SEN 2/CIRC-B2

EC-187

P0228

0228

TP SEN 2/CIRC-B2

EC-187

P0300

0300

MULTI CYL MISFIRE

EC-255

P0301

0301

CYL 1 MISFIRE

EC-255

P0302

0302

CYL 2 MISFIRE

EC-255

P0303

0303

CYL 3 MISFIRE

EC-255

P0304

0304

CYL 4 MISFIRE

EC-255

P0305

0305

CYL 5 MISFIRE

EC-255

P0306

0306

CYL 6 MISFIRE

EC-255

P0327

0327

KNOCK SEN/CIRC-B1

EC-261

P0328

0328

KNOCK SEN/CIRC-B1

EC-261

P0332

0332

KNOCK SEN/CIRC-B2

EC-261

P0333

0333

KNOCK SEN/CIRC-B2

EC-261

P0335

0335

CKP SEN/CIRCUIT

EC-264

P0340

0340

CMP SEN/CIRC-B1

EC-268

P0345

0345

CMP SEN/CIRC-B2

EC-268

P0420

0420

TW CATALYST SYS-B1

EC-272

P0430

0430

TW CATALYST SYS-B2

EC-272

P0441

0441

EVAP PURG FLOW/MON

EC-277

P0442

0442

EVAP SMALL LEAK

EC-282

P0443

0443

PURG VOLUME CONT/V

EC-288

P0444

0444

PURG VOLUME CONT/V

EC-293

P0445

0445

PURG VOLUME CONT/V

EC-293

P0447

0447

VENT CONTROL VALVE

EC-296

P0448

0448

VENT CONTROL VALVE

EC-300

P0451

0451

EVAP SYS PRES SEN

EC-304

P0452

0452

EVAP SYS PRES SEN

EC-307

P0453

0453

EVAP SYS PRES SEN

EC-312

Revision: 2007 June

EC-554

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DTC*1
CONSULT-III
GST*2
P0455

ECM*3
0455

SRT code

Trip

MIL

Reference
page

EVAP GROSS LEAK

EC-318

EC

EC-324

Items
(CONSULT-III screen terms)

P0456

0456

EVAP VERY SML LEAK

*6

P0460

0460

FUEL LEV SEN SLOSH

EC-331

P0461

0461

FUEL LEVEL SENSOR

EC-333

P0462

0462

FUEL LEVL SEN/CIRC

EC-335

P0463

0463

FUEL LEVL SEN/CIRC

EC-335

EC-337

SEN/CIRC*5

P0500

0500

VEH SPEED

P0506

0506

ISC SYSTEM

EC-339

P0507

0507

ISC SYSTEM

EC-341

P0524

0524

ENGINE OIL PRESSURE

EC-343

P0550

0550

PW ST P SEN/CIRC

EC-346

P0555

0555

BRAKE BSTR PRES SEN/CIRC

EC-349

P0603

0603

ECM BACK UP/CIRCUIT

EC-354

P0605

0605

ECM

1 or 2

or

EC-356

P0643

0643

SENSOR POWER/CIRC

EC-358

P0700

0700

TCM

TM-121

P0705

0705

PNP SW/CIRC

TM-122

P0710

0710

ATF TEMP SEN/CIRC

TM-144

P0717

0717

TURBINE SENSOR

TM-124

P0720

0720

VEH SPD SEN/CIR AT*5

TM-125

P0731

0731

A/T 1ST GR FNCTN

TM-130

P0732

0732

A/T 2ND GR FNCTN

TM-132

P0733

0733

A/T 3RD GR FNCTN

TM-134

P0734

0734

A/T 4TH GR FNCTN

TM-136

P0735

0735

A/T 5TH GR FNCTN

TM-138

P0740

0740

TCC SOLENOID/CIRC

TM-140

P0744

0744

A/T TCC S/V FNCTN

TM-141

P0745

0745

L/PRESS SOL/CIRC

TM-142

P0850

0850

P-N POS SW/CIRCUIT

EC-361

P100A

100A

VVEL SYSTEM-B1

EC-365

P100B

100B

VVEL SYSTEM-B2

EC-365

P1087

1087

VVEL SYSTEM-B1

EC-369

P1088

1088

VVEL SYSTEM-B2

EC-369

P1089

1089

VVEL POS SEN/CIRC-B1

EC-370

P1090

1090

VVEL ACTR MOT-B1

EC-374

P1091

1091

VVEL ACTR MOT PWR

1 or 2

EC-378

P1092

1092

VVEL POS SEN/CIRC-B2

EC-370

P1093

1093

VVEL ACTR MOT-B2

EC-374

P1148

1148

CLOSED LOOP-B1

EC-381

P1168

1168

CLOSED LOOP-B2

EC-381

P1211

1211

TCS C/U FUNCTN

EC-382

P1212

1212

TCS/CIRC

EC-383

Revision: 2007 June

EC-555

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DTC*1
CONSULT-III
GST*2

ECM*3

Items
(CONSULT-III screen terms)

SRT code

Trip

MIL

Reference
page

P1217

1217

ENG OVER TEMP

EC-384

P1225

1225

CTP LEARNING-B1

EC-388

P1226

1226

CTP LEARNING-B1

EC-390

P1233

1233

ETC FNCTN/CIRC-B2

EC-392

P1234

1234

CTP LEARNING-B2

EC-388

P1235

1235

CTP LEARNING-B2

EC-390

P1236

1236

ETC MOT-B2

EC-396

P1238

1238

ETC ACTR-B2

EC-399

P1239

1239

TP SENSOR-B2

EC-401

P1290

1290

ETC MOT PWR-B2

EC-404

P1421

1421

COLD START CONTROL

EC-406

P1550

1550

BAT CURRENT SENSOR

EC-408

P1551

1551

BAT CURRENT SENSOR

EC-411

P1552

1552

BAT CURRENT SENSOR

EC-411

P1553

1553

BAT CURRENT SENSOR

EC-414

P1554

1554

BAT CURRENT SENSOR

EC-417

P1564

1564

ASCD SW

EC-421
(with ASCD)
EC-424
(with ICC)

P1568

1568

ICC COMMAND VALUE

EC-427

EC-428
(with ASCD)
EC-435
(with ICC)

P1572

1572

ASCD BRAKE SW

EC-443
(with ASCD)
EC-445
(with ICC)

VVEL CONTROL MODULE

1 or 2

or

EC-447

VVEL CONTROL MODULE

EC-449

1608

VVEL SENSOR POWER/CIRC

EC-451

P1610

1610

LOCK MODE

SEC-38

P1611

1611

ID DISCARD IMM-ECM

SEC-39

P1612

1612

CHAIN OF ECM-IMMU

SEC-41

P1615

1615

DIFFERENCE OF KEY

SEC-45

P1715

1715

IN PULY SPEED

EC-454

P1574

1574

ASCD VHL SPD SEN

P1606

1606

P1607

1607

P1608

P1730

1730

A/T INTERLOCK

TM-148

P1752

1752

I/C SOLENOID/CIRC

TM-150

P1757

1757

FR/B SOLENOID/CIRC

TM-151

P1762

1762

D/C SOLENOID/CIRC

TM-152

P1767

1767

HLR/C SOL/CIRC

TM-153

P1772

1772

LC/B SOLENOID/CIRC

TM-154

P1774

1774

LC/B SOLENOID FNCT

TM-155

P1805

1805

BRAKE SW/CIRCUIT

EC-455

Revision: 2007 June

EC-556

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DTC*1
CONSULT-III
GST*2

ECM*3

Items
(CONSULT-III screen terms)

SRT code

Trip

MIL

Reference
page

EC

P2100

2100

ETC MOT PWR-B1

EC-404

P2101

2101

ETC FNCTN/CIRC-B1

EC-392

P2103

2103

ETC MOT PWR

EC-404

P2118

2118

ETC MOT-B1

EC-396

P2119

2119

ETC ACTR-B1

EC-399

P2122

2122

APP SEN 1/CIRC

EC-458

P2123

2123

APP SEN 1/CIRC

EC-458

P2127

2127

APP SEN 2/CIRC

EC-462

P2128

2128

APP SEN 2/CIRC

EC-462

P2132

2132

TP SEN 1/CIRC-B2

EC-252

P2133

2133

TP SEN 1/CIRC-B2

EC-252

P2135

2135

TP SENSOR-B1

EC-401

P2138

2138

APP SENSOR

EC-466

P2A00

2A00

A/F SENSOR1 (B1)

EC-471

P2A03

2A03

A/F SENSOR1 (B2)

EC-471

*1: 1st trip DTC No. is the same as DTC No.

*2: This number is prescribed by SAE J2012.

*3: In Diagnostic Test Mode II (Self-diagnostic results), this number is controlled by NISSAN.
*4: The troubleshooting for this DTC needs CONSULT-III.

*5: When the fail-safe operations for both self-diagnoses occur, the MIL illuminates.
*6: SRT code will not be set if the self-diagnostic result is NG.
*7: When the ECM is in the mode of displaying SRT status, MIL may flash. For the details, refer to How to Display SRT Status.

How to Set SRT Code

INFOID:0000000001734352

To set all SRT codes, self-diagnosis for the items indicated above must be performed one or more times. Each
diagnosis may require a long period of actual driving under various conditions.
WITH CONSULT-III
Perform corresponding DTC Confirmation Procedure one by one based on Performance Priority in the table
on SRT Item.
WITHOUT CONSULT-III
The most efficient driving pattern in which SRT codes can be properly set is explained on the next page. The
driving pattern should be performed one or more times to set all SRT codes.

Revision: 2007 June

EC-557

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

DRIVING PATTERN

PBIB3455E

The time required for each diagnosis varies with road surface conditions, weather, altitude, individual driving
habits, etc.
Zone A refers to the range where the time, required for the diagnosis under normal conditions*, is the shortest.
Zone B refers to the range where the diagnosis can still be performed if the diagnosis is not completed within
zone A.
*: Normal conditions refer to the following:
Revision: 2007 June

EC-558

G37 Coupe

ECM
[VQ37VHR]
< ECU DIAGNOSIS >
Sea level
Flat road
A
Ambient air temperature: 20 - 30C (68 - 86F)
Diagnosis is performed as quickly as possible under normal conditions.
Under different conditions [For example: ambient air temperature other than 20 - 30C (68 - 86F)], diagnoEC
sis may also be performed.
Pattern 1:
The engine is started at the engine coolant temperature of 10 to 35C (14 to 95F)
(where the voltage between the ECM terminal 71 and ground is 3.0 - 4.3V).
C
The engine must be operated at idle speed until the engine coolant temperature is greater than 70C
(158F) (where the voltage between the ECM terminal 71 and ground is lower than 1.4V).
The engine is started at the fuel tank temperature of warmer than 0C (32F) (where the voltage D
between the ECM terminal 106 and ground is less than 4.1V).
Pattern 2:
When steady-state driving is performed again even after it is interrupted, each diagnosis can be conducted.
E
In this case, the time required for diagnosis may be extended.
Pattern 3:
Operate vehicle following the driving pattern shown in the figure.
Release the accelerator pedal during decelerating vehicle speed
F
from 90 km/h (56 MPH) to 0 km/h (0 MPH).
Pattern 4:
The accelerator pedal must be held very steady during steadyG
state driving.
If the accelerator pedal is moved, the test must be conducted all
over again.
*1: Depress the accelerator pedal until vehicle speed is 90 km/h (56
H
MPH), then release the accelerator pedal and keep it released for
more than 10 seconds. Depress the accelerator pedal until vehicle
PBIB2244E
speed is 90 km/h (56 MPH) again.
I
*2: Checking the vehicle speed with GST is advised.
Suggested Transmission Gear Position for A/T Models
Set the selector lever in the D position with the overdrive switch turned ON.

Suggested Upshift Speeds for M/T Models

Shown below are suggested vehicle speeds for shifting into a higher gear. These suggestions relate to fuel
economy and vehicle performance. Actual upshift speeds will vary according to road conditions, the weather
and individual driving habits.

Unit: km/h (MPH)

Gear change

For normal acceleration in low altitude areas

[less than 1,219 m (4,000 ft)]

For quick acceleration in low altitude areas or in

high altitude areas [over 1,219 m (4,000 ft)]

1st to 2nd

13 (8)

24 (15)

2nd to 3rd

26 (16)

40 (25)

3rd to 4th

40 (25)

64 (40)

4th to 5th

50 (30)

72 (45)

5th to 6th

53 (33)

80 (50)

Suggested Maximum Speed in Each Gear

Downshift to a lower gear if the engine is not running smoothly, or if you need to accelerate.
Do not exceed the maximum suggested speed (shown below) in any gear. For level road driving, use the highest gear suggested for that speed. Always observe posted speed limits and drive according to the road conditions to ensure sage operation. Do not over-rev the engine when shifting to a lower gear as it may cause
engine damage or loss of vehicle control.

Revision: 2007 June

Gear

km/h (MPH)

1st

63 (39)

2nd

103 (64)

3rd

148 (92)

4th

EC-559

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Gear

km/h (MPH)

5th

6th

Test Value and Test Limit

INFOID:0000000001734353

The following is the information specified in Service $06 of SAE J1979.

The test value is a parameter used to determine whether a system/circuit diagnostic test is OK or NG while
being monitored by the ECM during self-diagnosis. The test limit is a reference value which is specified as the
maximum or minimum value and is compared with the test value being monitored.
These data (test value and test limit) are specified by Test ID (TID) and Component ID (CID) and can be displayed on the GST screen.

Item

OBDMID

01H

Self-diagnostic test item

Air fuel ratio (A/F) sensor 1

(Bank 1)

DTC

Test value and Test

limit
(GST display)
TID

P0131

83H

0BH

Minimum sensor output voltage

for test cycle

P0131

84H

0BH

Maximum sensor output voltage

for test cycle

P0130

85H

0BH

Minimum sensor output voltage

for test cycle

P0130

86H

0BH

Maximum sensor output voltage

for test cycle

P0133

87H

04H

Response rate: Response ratio

(Lean to Rich)

P0133

88H

04H

Response rate: Response ratio

(Rich to Lean)

P2A00

89H

84H

The amount of shift in air fuel ratio

P2A00

8AH

84H

The amount of shift in air fuel ratio

P0130

8BH

0BH

Difference in sensor output voltage

P0133

8CH

83H

Response gain at the limited frequency

P0138

07H

0CH

Minimum sensor output voltage

for test cycle

P0137

08H

0CH

Maximum sensor output voltage

for test cycle

P0138

80H

0CH

Sensor output voltage

P0139

81H

0CH

Difference in sensor output voltage

P0143

07H

0CH

Minimum sensor output voltage

for test cycle

P0144

08H

0CH

Maximum sensor output voltage

for test cycle

P0146

80H

0CH

Sensor output voltage

P0145

81H

0CH

Difference in sensor output voltage

HO2S

02H

03H

Revision: 2007 June

Heated oxygen sensor 2

(Bank 1)

Heated oxygen sensor 3

(Bank 1)

Description

Unit and
Scaling
ID

EC-560

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Item

OBDMID

Self-diagnostic test item

DTC

P0151

05H

Air fuel ratio (A/F) sensor 1

(Bank 2)

Test value and Test

limit
(GST display)

07H

21H

Heated oxygen sensor 2

(Bank 2)

Heated oxygen sensor 3

(Bank2)

Three way catalyst function

(Bank1)

CATALYST

22H

Revision: 2007 June

Three way catalyst function

(Bank2)

Description

TID

Unit and
Scaling
ID

83H

0BH

Minimum sensor output voltage

for test cycle

EC

P0151

84H

0BH

Maximum sensor output voltage

for test cycle

P0150

85H

0BH

Minimum sensor output voltage

for test cycle

P0150

86H

0BH

Maximum sensor output voltage

for test cycle

P0153

87H

04H

Response rate: Response ratio

(Lean to Rich)

P0153

88H

04H

Response rate: Response ratio

(Rich to Lean)

P2A03

89H

84H

The amount of shift in air fuel ratio

P2A03

8AH

84H

The amount of shift in air fuel ratio

P0150

8BH

0BH

Difference in sensor output voltage

P0153

8CH

83H

Response gain at the limited frequency

P0158

07H

0CH

Minimum sensor output voltage

for test cycle

HO2S

06H

P0157

08H

0CH

Maximum sensor output voltage

for test cycle

P0158

80H

0CH

Sensor output voltage

P0159

81H

0CH

Difference in sensor output voltage

P0163

07H

0CH

Minimum sensor output voltage

for test cycle

P0164

08H

0CH

Maximum sensor output voltage

for test cycle

P0166

80H

0CH

Sensor output voltage

P0165

81H

0CH

Difference in sensor output voltage

P0420

80H

01H

O2 storage index

P0420

82H

01H

Switching time lag engine exhaust

index value

P2423

83H

0CH

Difference in 3rd O2 sensor output voltage

P2423

84H

84H

O2 storage index in HC trap catalyst

P0430

80H

01H

O2 storage index

P0430

82H

01H

Switching time lag engine exhaust

index value

P2424

83H

0CH

Difference in 3rd O2 sensor output voltage

P2424

84H

84H

O2 storage index in HC trap catalyst

EC-561

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Item

EGR
SYSTEM

EVAP
SYSTEM

O2 SENSOR
HEATER

SECONDARY AIR

OBDMID

31H

Self-diagnostic test item

EGR function

DTC

Test value and Test

limit
(GST display)

Description

TID

Unit and
Scaling
ID

P0400

80H

96H

Low Flow Faults: EGR temp

change rate (short term)

P0400

81H

96H

Low Flow Faults: EGR temp

change rate (long term)

P0400

82H

96H

Low Flow Faults: Difference between max EGR temp and EGR
temp under idling condition

P0400

83H

96H

Low Flow Faults: Max EGR temp

P1402

84H

96H

High Flow Faults: EGR temp increase rate

39H

EVAP control system leak

(Cap Off)

P0455

80H

0CH

Difference in pressure sensor output voltage before and after pull

down

3BH

EVAP control system leak

(Small leak)

P0442

80H

05H

Leak area index (for more than

0.04inch)

P0456

80H

05H

Leak area index (for more than

0.02inch)

P0456

81H

FDH

Maximum internal pressure of

EVAP system during monitoring

P0441

83H

0CH

Difference in pressure sensor output voltage before and after vent

control value close

3CH

EVAP control system

(Very small leak)

3DH

Purge flow system

41H

A/F sensor 1 heater

(Bank 1)

Low Input:P0031
High Input:P0032

81H

0BH

Converted value of Heater electric

current to voltage

42H

Heated oxygen sensor 2

(Bank 1)

Low Input:P0037
High Input:P0038

80H

0CH

Converted value of Heater electric

current to voltage

43H

Heated oxygen sensor 3

(Bank 1)

P0043

80H

0CH

Converted value of Heater electric

current to voltage

45H

A/F sensor 1 heater

(Bank 2)

Low Input:P0051
High Input:P0052

81H

0BH

Converted value of Heater electric

current to voltage

46H

Heated oxygen sensor 2

(Bank 2)

Low Input:P0057
High Input:P0058

80H

0CH

Converted value of Heater electric

current to voltage

47H

Heated oxygen sensor 3

(Bank 2)

P0063

80H

0CH

Converted value of Heater electric

current to voltage

P0411

80H

01H

Secondary Air Injection System

Incorrect Flow Detected

Bank1: P0491
Bank2: P0492

81H

01H

Secondary Air Injection System

Insufficient Flow

P2445

82H

01H

Secondary Air Injection System

Pump Stuck Off

P2448

83H

01H

Secondary Air Injection System

High Airflow

Bank1: P2440
Bank2: P2442

84H

01H

Secondary Air Injection System

Switching Valve Stuck Open

P2440

85H

01H

Secondary Air Injection System

Switching Valve Stuck Open

P2444

86H

01H

Secondary Air Injection System

Pump Stuck On

71H

Revision: 2007 June

Secondary Air system

EC-562

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Item

OBDMID

Self-diagnostic test item

81H

Fuel injection system function

(Bank 1)

82H

Fuel injection system function

(Bank 2)

FUEL
SYSTEM

MISFIRE

A1H

Revision: 2007 June

DTC

Test value and Test

limit
(GST display)

A
Description

TID

Unit and
Scaling
ID

P0171 or P0172

80H

2FH

Long term fuel trim

P0171 or P0172

81H

24H

The number of lambda control

clamped

P0174 or P0175

80H

2FH

Long term fuel trim

P0174 or P0175

81H

24H

The number of lambda control

clamped

P0301

80H

24H

Misfiring counter at 1000rev of the

first cylinder

P0302

81H

24H

Misfiring counter at 1000rev of the

second cylinder

P0303

82H

24H

Misfiring counter at 1000rev of the

third cylinder

P0304

83H

24H

Misfiring counter at 1000rev of the

fourth cylinder

EC

P0305

84H

24H

Misfiring counter at 1000rev of the

fifth cylinder

P0306

85H

24H

Misfiring counter at 1000rev of the

sixth cylinder

P0307

86H

24H

Misfiring counter at 1000rev of the

seventh cylinder

P0308

87H

24H

Misfiring counter at 1000rev of the

eighth cylinder

P0300

88H

24H

Misfiring counter at 1000rev of the

multiple cylinders

P0301

89H

24H

Misfiring counter at 200rev of the

first cylinder

P0302

8AH

24H

Misfiring counter at 200rev of the

second cylinder

P0303

8BH

24H

Misfiring counter at 200rev of the

third cylinder

P0304

8CH

24H

Misfiring counter at 200rev of the

fourth cylinder

P0305

8DH

24H

Misfiring counter at 200rev of the

fifth cylinder

P0306

8EH

24H

Misfiring counter at 200rev of the

fifth cylinder

P0307

8FH

24H

Misfiring counter at 200rev of the

fifth cylinder

P0308

90H

24H

Misfiring counter at 200rev of the

fifth cylinder

P0300

91H

24H

Misfiring counter at 1000rev of the

single cylinder

P0300

92H

24H

Misfiring counter at 200rev of the

single cylinder

P0300

93H

24H

Misfiring counter at 200rev of the

multiple cylinders

Multiple Cylinder Misfire

EC-563

G37 Coupe

ECM
[VQ37VHR]

< ECU DIAGNOSIS >

Item

OBDMID

A2H

A3H

A4H

A5H

Self-diagnostic test item

DTC

Test value and Test

limit
(GST display)
TID

P0301

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0301

0CH

24H

Misfire counts for last/current driving cycles

P0302

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0302

0CH

24H

Misfire counts for last/current driving cycles

P0303

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0303

0CH

24H

Misfire counts for last/current driving cycles

P0304

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0304

0CH

24H

Misfire counts for last/current driving cycles

P0305

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0305

0CH

24H

Misfire counts for last/current driving cycles

P0306

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0306

0CH

24H

Misfire counts for last/current driving cycles

P0307

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0307

0CH

24H

Misfire counts for last/current driving cycles

P0308

0BH

24H

EWMA (Exponential Weighted

Moving Average) misfire counts
for last 10 driving cycles

P0308

0CH

24H

Misfire counts for last/current driving cycles

No.1 Cylinder Misfire

No.2 Cylinder Misfire

No.3 Cylinder Misfire

No.4 Cylinder Misfire

MISFIRE

A6H

A7H

A8H

A9H

Revision: 2007 June

Description

Unit and
Scaling
ID

No.5 Cylinder Misfire

No.6 Cylinder Misfire

No.7 Cylinder Misfire

No.8 Cylinder Misfire

EC-564

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

VVEL CONTROL MODULE

Reference Value

INFOID:0000000001903105

TERMINAL LAYOUT

EC

JMBIA0857ZZ

PHYSICAL VALUES
NOTE:
VVEL control module is located behind the IPDM E/R. For this inspection, remove hoodledge cover (RH).
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-III.

G
Terminal No.

Description

Signal name

1
(W)

14
(B)

VVEL actuator motor relay

power supply (bank 2)

Input

Value
(Approx.)

Condition

Input/
Output

H
[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

0 - 14V
[Engine is running]
Warm-up condition
Idle speed

2
(L/B)

14
(B)

VVEL actuator motor

(High lift) (bank 2)

JMBIA0854ZZ

Output
0 - 14V

[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

M
JMBIA0855ZZ

3
(G)

4
(W)

4
(W)

VVEL control shaft position sensor 2 (bank 1)

Sensor ground
[VVEL control shaft position sensor 2 (bank 1)]

Revision: 2007 June

Input

[Engine is running]
Warm-up condition
Idle speed

Approx.0.25 - 1.40V

[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

Approx.0.25 - 4.75V

EC-565

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
+

5
(R)

Description

6
(B)

Signal name

VVEL control shaft position sensor 2 (bank 2)

Input

Value
(Approx.)

Condition

Input/
Output

[Engine is running]
Warm-up condition
Idle speed

Approx.0.25 - 1.40V

[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

Approx.0.25 - 4.75V

6
(B)

Sensor ground
[VVEL control shaft position sensor 2 (bank 2)]

7
(SB)

6
(B)

Sensor power supply

[VVEL control shaft position sensor 2 (bank 2)]

[Ignition switch: ON]

5V

8
(O)

14
(B)

Power supply for VVEL

control module

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

9
(LG)

4
(W)

Sensor power supply

[VVEL control shaft position sensor 2 (bank 1)]

[Ignition switch: ON]

5V

11
(G)

CAN communication line

[ECM]

Input/
Output

0 - 14V

[Engine is running]
Warm-up condition
Idle speed
12
(G)

14
(B)

VVEL actuator motor

(High lift) (bank 1)

JMBIA0854ZZ

Output
0 - 14V
[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

JMBIA0855ZZ

13
(W)

14
(B)

VVEL actuator motor relay

power supply (bank 1)

14
(B)

Revision: 2007 June

Input

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

[Engine is running]
Idle speed

EC-566

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
+

Description

Signal name

Value
(Approx.)

Condition

Input/
Output

0 - 14V

EC

[Engine is running]
Warm-up condition
Idle speed

15
(L/Y)

14
(B)

VVEL actuator motor (Low

lift) (bank 2)

JMBIA0854ZZ

Output

0 - 14V
[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

F
JMBIA0855ZZ

16
(R)

17
(L)

18
(G)

17
(L)

19
(W)

VVEL control shaft position sensor 1 (bank 1)

Sensor ground
[VVEL control shaft position sensor 1 (bank 1)]

VVEL control shaft position sensor 1 (bank 2)

Input

Input

[Engine is running]
Warm-up condition
Idle speed

3.50 - 4.75V

[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

0.25 - 4.75V

[Engine is running]
Warm-up condition
Idle speed

3.50 - 4.75V

[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly

0.25 - 4.75V

19
(W)

Sensor ground
[VVEL control shaft position sensor 1 (bank 2)]

20
(BR)

19
(W)

Sensor power supply

[VVEL control shaft position sensor 1 (bank 2)]

[Ignition switch: ON]

5V

21
(V)

14
(B)

VVEL actuator motor relay

abort signal

Input

[Engine is running]
Warm-up condition
Idle speed

0V

22
(P)

17
(L)

Sensor power supply

[VVEL position sensor 1
(bank 1)]

[Ignition switch: ON]

5V

23
(Y)

14
(B)

VVEL control motor relay

Output

[Ignition switch: OFF]

BATTERY VOLTAGE
(11 - 14V)

[Ignition switch: ON]

0 - 1.0V

24
(L)

CAN communication line

Revision: 2007 June

Input/
Output

EC-567

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

Terminal No.
+

Description

Signal name

Value
(Approx.)

Condition

Input/
Output

0 - 14V
[Engine is running]
Warm-up condition
Idle speed

25
(BR)

14
(B)

VVEL control motor (Low

lift) (bank 1)

JMBIA0854ZZ

Output
0 - 14V
[Engine is running]
Warm-up condition
When revving engine up to 2,000
rpm quickly
JMBIA0855ZZ

: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)

Revision: 2007 June

EC-568

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

Wiring Diagram - ENGINE CONTROL SYSTEM -

INFOID:0000000001911753

Click here to view the eWD.

EC

P
JCBWA0348GB

Revision: 2007 June

EC-569

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0349GB

Revision: 2007 June

EC-570

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0350GB

Revision: 2007 June

EC-571

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0351GB

Revision: 2007 June

EC-572

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0352GB

Revision: 2007 June

EC-573

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0353GB

Revision: 2007 June

EC-574

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0354GB

Revision: 2007 June

EC-575

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0355GB

Revision: 2007 June

EC-576

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0356GB

Revision: 2007 June

EC-577

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0357GB

Revision: 2007 June

EC-578

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0358GB

Revision: 2007 June

EC-579

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0359GB

Revision: 2007 June

EC-580

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0360GB

Revision: 2007 June

EC-581

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0361GB

Revision: 2007 June

EC-582

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0362GB

Revision: 2007 June

EC-583

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0363GB

Revision: 2007 June

EC-584

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0364GB

Revision: 2007 June

EC-585

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0365GB

Revision: 2007 June

EC-586

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

EC

O
JCBWA0366GB

Revision: 2007 June

EC-587

G37 Coupe

VVEL CONTROL MODULE

[VQ37VHR]

< ECU DIAGNOSIS >

JCBWA0367GB

Revision: 2007 June

EC-588

G37 Coupe

ENGINE CONTROL SYSTEM SYMPTOMS

[VQ37VHR]

< SYMPTOM DIAGNOSIS >

SYMPTOM DIAGNOSIS

ENGINE CONTROL SYSTEM SYMPTOMS

Symptom Table

INFOID:0000000001734354

EC

SYSTEM BASIC ENGINE CONTROL SYSTEM

C

ROUGH IDLE/HUNTING

IDLING VIBRATION

SLOW/NO RETURN TO IDLE

OVERHEATS/WATER TEMPERATURE HIGH

EXCESSIVE FUEL CONSUMPTION

EXCESSIVE OIL CONSUMPTION

BATTERY DEAD (UNDER CHARGE)

AM

HA

LACK OF POWER/POOR ACCELERATION

AL

SPARK KNOCK/DETONATION

AK

HESITATION/SURGING/FLAT SPOT

AJ

ENGINE STALL

AH

AB

AC

AD

AE

Fuel pump circuit

Fuel pressure regulator system

Fuel injector circuit

Evaporative emission system

Positive crankcase ventilation system

3
4

E
Reference
page

H
EC-490

EC-601

EC-487

EC-81

EC-13

Incorrect ignition timing adjustment

EC-13

Ignition circuit

EC-498

EC-140

EC-165,
EC-172

Mass air flow sensor circuit

1
Engine coolant temperature sensor circuit

EC-184,
EC-190

3
1

2
3

Knock sensor circuit

Revision: 2007 June

EC-458,
EC-462,
EC-466

EC-589

EC-197,
EC-201,
EC-204,
EC-207,
EC-471
EC-187,
EC-252,
EC-388,
EC-390,
EC-401

Throttle position sensor circuit

Accelerator pedal position sensor circuit

EC-392,
EC-399

Air fuel ratio (A/F) sensor 1 circuit

EC-509

Electric throttle control actuator

Main power supply and ground circuit

Incorrect idle speed adjustment

Ignition

AG

HARD/NO START/RESTART (EXCP. HA)

Air

AF

AA

Warranty symptom code

Fuel

HIGH IDLE/LOW IDLE

SYMPTOM

EC-261

G37 Coupe

ENGINE CONTROL SYSTEM SYMPTOMS

[VQ37VHR]

< SYMPTOM DIAGNOSIS >

ENGINE STALL

HESITATION/SURGING/FLAT SPOT

SPARK KNOCK/DETONATION

LACK OF POWER/POOR ACCELERATION

HIGH IDLE/LOW IDLE

ROUGH IDLE/HUNTING

IDLING VIBRATION

SLOW/NO RETURN TO IDLE

OVERHEATS/WATER TEMPERATURE HIGH

EXCESSIVE FUEL CONSUMPTION

EXCESSIVE OIL CONSUMPTION

BATTERY DEAD (UNDER CHARGE)

Warranty symptom code

HARD/NO START/RESTART (EXCP. HA)

SYMPTOM

AA

AB

AC

AD

AE

AF

AG

AH

AJ

AK

AL

AM

HA

Engine oil temperature sensor

Reference
page

EC-246,
EC-249

Crankshaft position sensor (POS) circuit

EC-264

Camshaft position sensor (PHASE) circuit

EC-268

Vehicle speed signal circuit

Power steering pressure sensor circuit

3
3

EC-337
EC-346

EC-354,
EC-356

EC-162

Manifold abslute pressure (MAP) sensor

EC-177

Brake booster pressure sensor

EC-349

ECM

Intake valve timing control solenoid valve circuit

VVEL control module

EC447,EC449

VVEL actuator motor

EC-374

VVEL actuator motor relay

EC-378

VVEL actuator shaft position sensor

EC-370

PNP switch circuit

Refrigerant pressure sensor circuit

3
3

Electrical load signal circuit

Air conditioner circuit
ABS actuator and electric unit (control unit)

3
3

EC-361

EC-511

3
2

EC-485
3

HAC-5
BRC-4

1 - 6: The numbers refer to the order of inspection.

(continued on next page)

SYSTEM ENGINE MECHANICAL & OTHER

Revision: 2007 June

EC-590

G37 Coupe

ENGINE CONTROL SYSTEM SYMPTOMS

[VQ37VHR]

< SYMPTOM DIAGNOSIS >

SYMPTOM

Fuel

Fuel tank
Fuel piping

HARD/NO START/RESTART (EXCP. HA)

ENGINE STALL

HESITATION/SURGING/FLAT SPOT

SPARK KNOCK/DETONATION

LACK OF POWER/POOR ACCELERATION

HIGH IDLE/LOW IDLE

ROUGH IDLE/HUNTING

IDLING VIBRATION

SLOW/NO RETURN TO IDLE

OVERHEATS/WATER TEMPERATURE HIGH

EXCESSIVE FUEL CONSUMPTION

EXCESSIVE OIL CONSUMPTION

BATTERY DEAD (UNDER CHARGE)

Warranty symptom code

AA

AB

AC

AD

AE

AF

AG

AH

AJ

AK

AL

AM

HA

Air

EM-27

Air cleaner

EM-27

5
5

EM-28

Battery

PG-96

K
1

CHG-22,
CHG-23

Starter circuit

Signal plate

EM-120

PNP switch

TM-9, TM122

Cylinder head gasket

EM-32

Cylinder head

EM-27

Air leakage from intake manifold/

Collector/Gasket

Generator circuit

Air duct

Electric throttle control actuator

Engine

Air leakage from air duct

(Mass air flow sensor electric
throttle control actuator)

Cranking

FL-4

Valve deposit
Poor fuel (Heavy weight gasoline,
Low octane)

C
Reference
page

FL-11

Vapor lock

EC

STR-17

EM-106

Cylinder block
4

Piston
Piston ring
Connecting rod

O
EM-120

Bearing
Crankshaft

Revision: 2007 June

EC-591

G37 Coupe

ENGINE CONTROL SYSTEM SYMPTOMS

[VQ37VHR]

< SYMPTOM DIAGNOSIS >

Valve
mechanism

ENGINE STALL

HESITATION/SURGING/FLAT SPOT

SPARK KNOCK/DETONATION

LACK OF POWER/POOR ACCELERATION

HIGH IDLE/LOW IDLE

ROUGH IDLE/HUNTING

IDLING VIBRATION

SLOW/NO RETURN TO IDLE

OVERHEATS/WATER TEMPERATURE HIGH

EXCESSIVE FUEL CONSUMPTION

EXCESSIVE OIL CONSUMPTION

BATTERY DEAD (UNDER CHARGE)

Warranty symptom code

HARD/NO START/RESTART (EXCP. HA)

SYMPTOM

AA

AB

AC

AD

AE

AF

AG

AH

AJ

AK

AL

AM

HA

Timing chain

EM-62

Camshaft

EM-93

Intake valve timing control

Intake valve

Exhaust manifold/Tube/Muffler/
Gasket

EM-62
3

Exhaust valve
Exhaust

Reference
page

EM-106

EX-4, EX-6

LU-9, LU11, LU-12,

LU-13

Three way catalyst

Lubrication

Cooling

Oil pan/Oil strainer/Oil pump/Oil

filter/Oil gallery/Oil cooler

Oil level (Low)/Filthy oil

,LU-6

Radiator/Hose/Radiator filler cap

CO-12,
CO-12

Thermostat
Water pump
Water gallery

5
5

Cooling fan

CO-21
CO-25
CO-18

Coolant level (Low)/Contaminated coolant

IVIS (INFINITI Vehicle Immobilizer System
NATS)

CO-23

CO-8
SEC-5

1 - 6: The numbers refer to the order of inspection.

Revision: 2007 June

EC-592

G37 Coupe

NORMAL OPERATING CONDITION

[VQ37VHR]

< SYMPTOM DIAGNOSIS >

NORMAL OPERATING CONDITION

Description

A
INFOID:0000000001734355

FUEL CUT CONTROL (AT NO LOAD AND HIGH ENGINE SPEED)

EC

If the engine speed is above 1,400 rpm under no load (for example, the selector lever position is neutral and
engine speed is over 1,400 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies based on engine speed. However, if the engine speed is above 4,000 rpm, fuel will be cut off in a few seconds. Fuel cut will be operated until the engine speed reaches 1,000 rpm, then fuel cut will be cancelled.
NOTE:
This function is different from deceleration control listed under Multiport Fuel Injection (MFI) System, EC-34,
"System Description".

TORQUE CUT CONTROL (AT HIGH ENGINE OIL TEMPERATURE)

ECM receives engine oil temperature signal from engine oil temperature sensor.
To avoid VVEL performance, ECM performs the engine torque cut control at high engine oil temperature.
If engine oil temperature is too high, engine oil viscosity will change. As a result, engine oil pressure is
decreased. This control is to control the VVEL operating angle by operating the VVEL actuator sub assembly.
If this control is operated, engine performance will decrease, then maximum engine speed is reduced a little,
for example.
NOTE:
If the engine oil temperature sensor is deteriorated, its characteristic will change.
In this case, the operating temperature for engine torque cut control might be decrease.
Perform Component Inspection of the engine oil temperature sensor to check for the deterioration.
Refer to EC-248, "Component Inspection".

Revision: 2007 June

EC-593

G37 Coupe

PRECAUTIONS
[VQ37VHR]

< PRECAUTION >

PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"

INFOID:0000000001912134

The Supplemental Restraint System such as AIR BAG and SEAT BELT PRE-TENSIONER, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS AIRBAG and SEAT BELT of this
Service Manual.
WARNING:
To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal
injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag
Module, see the SRS AIRBAG.
Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or harness connectors.

Precaution for Procedure without Cowl Top Cover

INFOID:0000000001912135

When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.

PIIB3706J

Precautions For Xenon Headlamp Service

INFOID:0000000001912136

WARNING:
Comply with the following warnings to prevent any serious accident.
Disconnect the battery cable (negative terminal) or the power supply fuse before installing, removing, or touching the xenon headlamp (bulb included). The xenon headlamp contains high-voltage
generated parts.
Never work with wet hands.
Check the xenon headlamp ON-OFF status after assembling it to the vehicle. Never turn the xenon
headlamp ON in other conditions. Connect the power supply to the vehicle-side connector.
(Turning it ON outside the lamp case may cause fire or visual impairments.)
Never touch the bulb glass immediately after turning it OFF. It is extremely hot.
CAUTION:
Comply with the following cautions to prevent any error and malfunction.
Install the xenon bulb securely. (Insufficient bulb socket installation may melt the bulb, the connector, the housing, etc. by high-voltage leakage or corona discharge.)
Never perform HID circuit inspection with a tester.
Never touch the xenon bulb glass with hands. Never put oil and grease on it.
Dispose of the used xenon bulb after packing it in thick vinyl without breaking it.
Never wipe out dirt and contamination with organic solvent (thinner, gasoline, etc.).

Revision: 2007 June

EC-594

G37 Coupe

PRECAUTIONS
[VQ37VHR]

< PRECAUTION >

On Board Diagnostic (OBD) System of Engine and A/T

INFOID:0000000001734359

A
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
EC
Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any repair
or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will C
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
Certain systems and components, especially those related to OBD, may use a new style slide-lock- D
ing type harness connector. For description and how to disconnect, refer to PG-86, "Description".
Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to light up due to the short circuit.
Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube E
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.
Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and F
TCM (Transmission control module) before returning the vehicle to the customer.

General Precautions

INFOID:0000000001734360

Always use a 12 volt battery as power source.

Do not attempt to disconnect battery cables while engine is
running.
Before connecting or disconnecting the ECM harness connector, turn ignition switch OFF and disconnect negative battery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
Before removing parts, turn ignition switch OFF and then disconnect battery ground cable.

J
SEF289H

Do not disassemble ECM.

If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is disconnected. However, this is not an indication of a malfunction. Do not replace parts because of a slight variation.
If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values

JMBIA0057ZZ

Revision: 2007 June

EC-595

G37 Coupe

PRECAUTIONS
< PRECAUTION >
When connecting ECM harness connector (A), fasten (B) it
securely with a lever as far as it will go as shown in the figure.
1.

ECM

C.

Loosen

[VQ37VHR]

JMBIA0029ZZ

When connecting or disconnecting pin connectors into or

from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) voltage to develop in coil and condenser, thus resulting in damage to ICs.
Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to prevent engine control system malfunctions due to receiving external noise, degraded operation
of ICs, etc.
Keep engine control system parts and harness dry.
Before replacing ECM, perform ECM Terminals and Reference
Value inspection and make sure ECM functions properly.
Refer to EC-513, "Reference Value".
Handle mass air flow sensor carefully to avoid damage.
Do not clean mass air flow sensor with any type of detergent.
Do not disassemble electric throttle control actuator.
Even a slight leak in the air intake system can cause serious
incidents.
Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).

PBIB0090E

MEF040D

After performing each TROUBLE DIAGNOSIS, perform DTC

Confirmation Procedure or Component Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Component Function Check should be a good result if the repair is completed.

SEF217U

Revision: 2007 June

EC-596

G37 Coupe

PRECAUTIONS
< PRECAUTION >
When measuring ECM signals with a circuit tester, never allow
the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the
ground.

[VQ37VHR]
A

EC

G
SEF348N

B1 indicates the bank 1, B2 indicates the bank 2 as shown in

the figure.
Do not operate fuel pump when there is no fuel in lines.
Tighten fuel hose clamps to the specified torque.

SEC893C

Do not depress accelerator pedal when starting.

Immediately after starting, do not rev up engine unnecessarily.
Do not rev up engine just prior to shutdown.

N
SEF709Y

Revision: 2007 June

EC-597

G37 Coupe

PRECAUTIONS
< PRECAUTION >
When installing C.B. ham radio or a mobile phone, be sure to
observe the following as it may adversely affect electronic
control systems depending on installation location.
- Keep the antenna as far as possible from the electronic control units.
- Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
- Adjust the antenna and feeder line so that the standing-wave
ratio can be kept smaller.
- Be sure to ground the radio to vehicle body.

Revision: 2007 June

EC-598

[VQ37VHR]

SEF708Y

G37 Coupe

PREPARATION
[VQ37VHR]

< PREPARATION >

PREPARATION

PREPARATION
Special Service Tools

INFOID:0000000001734361

NOTE:
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool name

EC

Description

D
Checking fuel pressure

(J-44321)
Fuel pressure gauge
kit

F
LEC642

Commercial Service Tools

INFOID:0000000001734362

Tool name
(Kent-Moore No.)

Description

Leak detector
i.e.: (J-41416)

Locating the EVAP leak

J
S-NT703

Applying positive pressure through EVAP service

port

EVAP service port

adapter
i.e.: (J-41413-OBD)

S-NT704

Fuel filler cap adapter

i.e.: (MLR-8382)

Checking fuel tank vacuum relief valve opening

pressure

O
S-NT815

Socket wrench

Removing and installing engine coolant temperature sensor

S-NT705

Revision: 2007 June

EC-599

G37 Coupe

PREPARATION
[VQ37VHR]

< PREPARATION >

Tool name
(Kent-Moore No.)

Description
Reconditioning the exhaust system threads before
installing a new oxygen sensor. Use with antiseize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for Titania Oxygen Sensor

Oxygen sensor thread

cleaner
i.e.: (J-43897-18)
(J-43897-12)

AEM488

Anti-seize lubricant

Lubricating oxygen sensor thread cleaning tool

when reconditioning exhaust system threads.

i.e.: (PermatexTM
133AR or equivalent
meeting MIL specification MIL-A-907)

S-NT779

Revision: 2007 June

EC-600

G37 Coupe

FUEL PRESSURE
[VQ37VHR]

< ON-VEHICLE MAINTENANCE >

ON-VEHICLE MAINTENANCE

FUEL PRESSURE
Inspection

INFOID:0000000001734363

EC

FUEL PRESSURE RELEASE

C

With CONSULT-III

1.
2.
3.
4.
5.

Turn ignition switch ON.

Perform FUEL PRESSURE RELEASE in WORK SUPPORT mode with CONSULT-III.
Start engine.
After engine stalls, crank it two or three times to release all fuel pressure.
Turn ignition switch OFF.

Without CONSULT-III

1.
2.
3.
4.
5.

Remove fuel pump fuse (1) located in IPDM E/R (2).

Start engine.
After engine stalls, crank it two or three times to release all fuel
pressure.
Turn ignition switch OFF.
Reinstall fuel pump fuse after servicing fuel system.

JMBIA0021ZZ

FUEL PRESSURE CHECK

CAUTION:
Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel
pressure cannot be completely released because CV36 models do not have fuel return system.
Use Fuel Pressure Gauge Kit (J-44321) to check fuel pressure.
1. Release fuel pressure to zero.
2. Install the inline fuel quick disconnected fitting (A) between fuel
damper (1) and injector tube.
3. Connect the fuel pressure test gauge (quick connector adapter
hose) (B) to the inline fuel quick disconnected fitting.
4. Turn ignition switch ON and check for fuel leakage.
5. Start engine and check for fuel leakage.
6. Read the indication of fuel pressure gauge.

At idling : Approximately 350 kPa (3.57 kg/cm2, 51 psi)

7.

If result is unsatisfactory, check fuel hoses and fuel tubes for

clogging.
If OK, Replace fuel filter and fuel pump assembly.
If NG, Repair or replace.

Revision: 2007 June

EC-601

JMBIA0028ZZ

G37 Coupe

EVAP LEAK CHECK

[VQ37VHR]

< ON-VEHICLE MAINTENANCE >

EVAP LEAK CHECK

Inspection

INFOID:0000000001734364

CAUTION:
Do not use compressed air or a high pressure pump.
Do not exceed 4.12 kPa (0.042 kg/cm2, 0.6 psi) of pressure in EVAP system.
NOTE:
Do not start engine.
Improper installation of EVAP service port adapter to the EVAP service port may cause a leak.

WITH CONSULT-III
1.
2.
3.
4.
5.
6.
7.

To locate the EVAP leak, install EVAP service port adapter and
pressure pump to EVAP service port.
Turn ignition switch ON.
Select the EVAP SYSTEM CLOSE of WORK SUPPORT
mode with CONSULT-III.
Touch START. A bar graph (Pressure indicating display) will
appear on the screen.
Apply positive pressure to the EVAP system until the pressure
indicator reaches the middle of the bar graph.
Remove EVAP service port adapter and hose with pressure
pump.
Locate the leak using a leak detector. Refer to EC-80, "System
Diagram".

SEF462UA

SEF200U

WITHOUT CONSULT-III
1.
2.
3.

4.

To locate the EVAP leak, install EVAP service port adapter and
pressure pump to EVAP service port.
Apply battery voltage between the terminals of EVAP canister
vent control valve to make a closed EVAP system.
To locate the leak, deliver positive pressure to the EVAP system
until pressure gauge points reach 1.38 to 2.76 kPa (0.014 to
0.028 kg/cm2, 0.2 to 0.4 psi).
Remove EVAP service port adapter and hose with pressure
pump.
SEF462UA

Revision: 2007 June

EC-602

G37 Coupe

EVAP LEAK CHECK

< ON-VEHICLE MAINTENANCE >
5. Locate the leak using a leak detector. Refer to EC-80, "System
Diagram".

[VQ37VHR]
A

EC

C
SEF200U

Revision: 2007 June

EC-603

G37 Coupe

EVAP CANISTER
[VQ37VHR]

< ON-VEHICLE REPAIR >

ON-VEHICLE REPAIR
EVAP CANISTER
Exploded View

INFOID:0000000001734365

JMBIA0049GB

1.

EVAP canister system pressure sen- 2.

sor

O-ring

4.

O-ring

EVAP canister vent control valve

5.

3.

EVAP canister

Refer to GI-3, "Contents" for symbols not described on the above.

Removal and Installation

INFOID:0000000001734366

REMOVAL
1. Lift up the vehicle.
2. Remove EVAP canister fixing bolt.
3. Remove EVAP canister.
NOTE:
The EVAP canister vent control valve and EVAP canister system pressure sensor can be removed without
removing the EVAP canister.

INSTALLATION
Install in the reverse order of removal.
NOTE:
Tighten EVAP canister fixing bolt to the specified torque.

DISASSEMBLY
1.

2.

Turn EVAP canister vent control valve counterclockwise.

A

: Lock

: Unlock

Remove the EVAP canister vent control valve.

PBIB2730E

Revision: 2007 June

EC-604

G37 Coupe

EVAP CANISTER
[VQ37VHR]

< ON-VEHICLE REPAIR >

ASSEMBLY
Assemble in the reverse order of disassembly.
CAUTION:
Always replace O-ring with a new one.

Inspection

INFOID:0000000001734367

Check EVAP canister as follows:

1. Block port (B).
2. Blow air into port (A) and check that it flows freely out of port (C).
3. Release blocked port (B).
4. Apply vacuum pressure to port (B) and check that vacuum pressure exists at the ports (A) and (C).
5. Block port (A) and (B).
6. Apply pressure to port (C) and check that there is no leakage.

EC

E
PBIB2728E

Revision: 2007 June

EC-605

G37 Coupe

SERVICE DATA AND SPECIFICATIONS (SDS)

[VQ37VHR]

< SERVICE DATA AND SPECIFICATIONS (SDS)

SERVICE DATA AND SPECIFICATIONS (SDS)

SERVICE DATA AND SPECIFICATIONS (SDS)
Idle Speed

INFOID:0000000001734368

Transmission

Condition

Specification

A/T

No load* (in P or N position)

650 50 rpm

M/T

No load* (in Neutral position)

650 50 rpm

*: Under the following conditions

A/C switch: OFF
Electric load: OFF (Lights, heater fan & rear window defogger)
Steering wheel: Kept in straight-ahead position

Ignition Timing

INFOID:0000000001734369

Transmission

Condition

Specification

A/T

No load* (in P or N position)

10 5 BTDC

M/T

No load* (in Neutral position)

10 5 BTDC

*: Under the following conditions

A/C switch: OFF
Electric load: OFF (Lights, heater fan & rear window defogger)
Steering wheel: Kept in straight-ahead position

Calculated Load Value

INFOID:0000000001734370

Condition

Specification (Using CONSULT-III or GST)

At idle

5 35 %

At 2,500 rpm

5 35 %

Mass Air Flow Sensor

INFOID:0000000001734371

Supply voltage

Battery voltage (11 14 V)

Output voltage at idle

0.7 1.2 V*
2.0 6.0 gm/sec at idle*
7.0 20.0 gm/sec at 2,500 rpm*

Mass air flow (Using CONSULT-III or GST)

*: Engine is warmed up to normal operating temperature and running under no load.

Revision: 2007 June

EC-606

G37 Coupe