D DRIVELINE/AXLE

SECTION TF
TRANSFER
B

TF

E
CONTENTS
PRECAUTIONS .......................................................... 4 4WD SHIFT SWITCH AND INDICATOR LAMP... 18 F
Precautions for Supplemental Restraint System 4WD WARNING LAMP ....................................... 19
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN- ATP WARNING LAMP ......................................... 19
SIONER” .................................................................. 4 System Diagram ..................................................... 19 G
Precautions for Transfer Assembly and Transfer COMPONENTS FUNCTION ............................... 20
Control Unit Replacement ........................................ 4 CAN Communication .............................................. 20
METHOD FOR POSITION ADJUSTMENT ........... 4 SYSTEM DESCRIPTION .................................... 20
H
Precautions .............................................................. 4 TROUBLE DIAGNOSIS ............................................ 21
Service Notice .......................................................... 5 How to Perform Trouble Diagnosis ......................... 21
Wiring Diagrams and Trouble Diagnosis .................. 5 BASIC CONCEPT ............................................... 21
PREPARATION ........................................................... 6 Location of Electrical Parts ..................................... 22 I
Special Service Tools ............................................... 6 Circuit Diagram ....................................................... 23
Commercial Service Tools ........................................ 9 Wiring Diagram — T/F — ....................................... 24
NOISE, VIBRATION AND HARSHNESS (NVH) Inspections Before Trouble Diagnosis .................... 32 J
TROUBLESHOOTING .............................................. 10 TRANSFER FLUID CHECK ................................ 32
NVH Troubleshooting Chart ................................... 10 PREPARATION FOR ROAD TEST ..................... 32
TRANSFER FLUID ....................................................11 CHECK BEFORE ENGINE IS STARTED ........... 32
K
Replacement ...........................................................11 CHECK AT IDLE .................................................. 32
DRAINING ............................................................11 CRUISE TEST ..................................................... 34
FILLING ................................................................11 Trouble Diagnosis Chart for Symptoms .................. 34
Inspection ................................................................11 Transfer Control Unit Input/Output Signal Refer- L
FLUID LEAKAGE AND FLUID LEVEL .................11 ence Values ............................................................ 36
ALL-MODE 4WD SYSTEM ...................................... 12 TRANSFER CONTROL UNIT INSPECTION
Cross-section View ................................................ 12 TABLE ................................................................. 36 M
Power Transfer ....................................................... 13 CONSULT-II Function (ALL MODE AWD/4WD) ..... 44
POWER TRANSFER DIAGRAM ........................ 13 FUNCTION .......................................................... 44
POWER TRANSFER FLOW ............................... 14 CONSULT-II SETTING PROCEDURE ................ 44
System Description ................................................ 15 SELF-DIAG RESULT MODE ............................... 45
CONTROL SYSTEM ........................................... 15 DATA MONITOR MODE ...................................... 47
TRANSFER MOTOR .......................................... 16 WORK SUPPORT ............................................... 49
WAIT DETECTION SWITCH .............................. 17 Self-diagnostic Procedure ...................................... 50
NEUTRAL-4LO SWITCH .................................... 17 SELF-DIAGNOSTIC PROCEDURE (WITH
ATP SWITCH ...................................................... 17 CONSULT-II) ....................................................... 50
2-4WD SHIFT SOLENOID VALVE ...................... 17 SELF-DIAGNOSTIC PROCEDURE (WITHOUT
CLUTCH PRESSURE SOLENOID VALVE ......... 17 CONSULT-II) ....................................................... 50
LINE PRESSURE SWITCH ................................ 18 ERASE SELF-DIAGNOSIS ................................. 53
CLUTCH PRESSURE SWITCH .......................... 18 TROUBLE DIAGNOSIS FOR SYSTEM .................... 54
TRANSFER FLUID TEMPERATURE SENSOR... 18 Power Supply Circuit For Transfer Control Unit ...... 54
TRANSFER CONTROL UNIT ............................. 18 CONSULT-II REFERENCE VALUE IN DATA
TRANSFER CONTROL DEVICE ........................ 18 MONITOR MODE ................................................ 54

Revision: October 2005 TF-1 2005 QX56

 TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE ..........................................86
REFERENCE VALUE .......................................... 54 DIAGNOSTIC PROCEDURE ...............................87
DIAGNOSTIC PROCEDURE .............................. 55 COMPONENT INSPECTION ...............................90
COMPONENT INSPECTION .............................. 57 2-4WD Solenoid ......................................................91
Transfer Control Unit .............................................. 57 CONSULT-II REFERENCE VALUE IN DATA
DIAGNOSTIC PROCEDURE .............................. 57 MONITOR MODE ................................................91
Output Shaft Revolution Signal (TCM) ................... 58 TRANSFER CONTROL UNIT TERMINALS AND
DIAGNOSTIC PROCEDURE .............................. 58 REFERENCE VALUE ..........................................91
Vehicle Speed Sensor (ABS) .................................. 58 DIAGNOSTIC PROCEDURE ...............................91
DIAGNOSTIC PROCEDURE .............................. 58 COMPONENT INSPECTION ...............................94
Neutral-4LO Switch ................................................ 59 Transfer Motor .........................................................95
CONSULT-II REFERENCE VALUE IN DATA CONSULT-II REFERENCE VALUE IN DATA
MONITOR MODE ................................................ 59 MONITOR MODE ................................................95
TRANSFER CONTROL UNIT TERMINALS AND TRANSFER CONTROL UNIT TERMINALS AND
REFERENCE VALUE .......................................... 59 REFERENCE VALUE ..........................................96
DIAGNOSTIC PROCEDURE .............................. 60 DIAGNOSTIC PROCEDURE ...............................97
COMPONENT INSPECTION .............................. 62 COMPONENT INSPECTION ............................. 102
4WD Shift Switch .................................................... 62 Transfer Fluid Temperature ................................... 102
CONSULT-II REFERENCE VALUE IN DATA CONSULT-II REFERENCE VALUE IN DATA
MONITOR MODE ................................................ 62 MONITOR MODE .............................................. 102
TRANSFER CONTROL UNIT TERMINALS AND TRANSFER CONTROL UNIT TERMINALS AND
REFERENCE VALUE .......................................... 62 REFERENCE VALUE ........................................ 102
DIAGNOSTIC PROCEDURE .............................. 63 DIAGNOSTIC PROCEDURE ............................. 103
COMPONENT INSPECTION .............................. 66 COMPONENT INSPECTION ............................. 104
Wait Detection Switch ............................................. 66 Clutch Pressure Switch ......................................... 105
CONSULT-II REFERENCE VALUE IN DATA CONSULT-II REFERENCE VALUE IN DATA
MONITOR MODE ................................................ 66 MONITOR MODE .............................................. 105
TRANSFER CONTROL UNIT TERMINALS AND TRANSFER CONTROL UNIT TERMINALS AND
REFERENCE VALUE .......................................... 66 REFERENCE VALUE ........................................ 105
DIAGNOSTIC PROCEDURE .............................. 67 DIAGNOSTIC PROCEDURE ............................. 106
COMPONENT INSPECTION .............................. 69 COMPONENT INSPECTION ............................. 107
PNP Switch Signal (TCM) ...................................... 69 Line Pressure Switch ............................................ 108
DIAGNOSTIC PROCEDURE .............................. 69 CONSULT-II REFERENCE VALUE IN DATA
Actuator Motor ........................................................ 70 MONITOR MODE .............................................. 108
CONSULT-II REFERENCE VALUE IN DATA TRANSFER CONTROL UNIT TERMINALS AND
MONITOR MODE ................................................ 70 REFERENCE VALUE ........................................ 108
TRANSFER CONTROL UNIT TERMINALS AND DIAGNOSTIC PROCEDURE ............................. 109
REFERENCE VALUE .......................................... 70 COMPONENT INSPECTION ............................. 110
DIAGNOSTIC PROCEDURE .............................. 71 Throttle Position Signal (ECM) .............................. 111
COMPONENT INSPECTION .............................. 76 DIAGNOSTIC PROCEDURE ............................. 111
Actuator Position Switch ......................................... 77 ABS Operation Signal (ABS) ................................ 111
CONSULT-II REFERENCE VALUE IN DATA DIAGNOSTIC PROCEDURE ............................. 111
MONITOR MODE ................................................ 77 VDC Operation Signal (ABS) ................................ 112
TRANSFER CONTROL UNIT TERMINALS AND DIAGNOSTIC PROCEDURE ............................. 112
REFERENCE VALUE .......................................... 77 TCS Operation Signal (ABS) ................................ 112
DIAGNOSTIC PROCEDURE .............................. 78 DIAGNOSTIC PROCEDURE ............................. 112
COMPONENT INSPECTION .............................. 80 CAN Communication Line ..................................... 113
Transfer Control Device .......................................... 81 DIAGNOSTIC PROCEDURE ............................. 113
CONSULT-II REFERENCE VALUE IN DATA ATP Switch ............................................................ 113
MONITOR MODE ................................................ 81 CONSULT-II REFERENCE VALUE IN DATA
TRANSFER CONTROL UNIT TERMINALS AND MONITOR MODE .............................................. 113
REFERENCE VALUE .......................................... 81 TRANSFER CONTROL UNIT TERMINALS AND
DIAGNOSTIC PROCEDURE .............................. 82 REFERENCE VALUE ........................................ 113
Engine Speed Signal (ECM) ................................... 85 DIAGNOSTIC PROCEDURE ............................. 114
DIAGNOSTIC PROCEDURE .............................. 85 COMPONENT INSPECTION ............................. 115
Clutch Pressure Solenoid ....................................... 86 TROUBLE DIAGNOSIS FOR SYMPTOMS ............ 117
CONSULT-II REFERENCE VALUE IN DATA 4WD Shift Indicator Lamp and 4LO Indicator Lamp
MONITOR MODE ................................................ 86 Do Not Turn ON .................................................... 117
TRANSFER CONTROL UNIT TERMINALS AND SYMPTOM: ........................................................ 117

Revision: October 2005 TF-2 2005 QX56

 DIAGNOSTIC PROCEDURE .............................117 SIDE OIL SEAL ....................................................... 137
4WD Warning Lamp Does Not Turn ON .............. 121 Removal and Installation ...................................... 137 A
SYMPTOM: ....................................................... 121 REMOVAL ......................................................... 137
DIAGNOSTIC PROCEDURE ............................ 121 INSTALLATION ................................................. 137
4WD Shift Indicator Lamp or 4LO Indicator Lamp TRANSFER CONTROL DEVICE ............................ 138 B
Does Not Change ................................................. 123 Removal and Installation ...................................... 138
SYMPTOM: ....................................................... 123 AIR BREATHER HOSE .......................................... 139
DIAGNOSTIC PROCEDURE ............................ 124 Removal and Installation ...................................... 139
ATP Warning Lamp Turns ON .............................. 125 TRANSFER MOTOR ............................................... 140 C
SYMPTOM: ....................................................... 125 Removal and Installation ...................................... 140
DIAGNOSTIC PROCEDURE ............................ 125 REMOVAL ......................................................... 140
4LO Indicator Lamp Repeats Flashing ................. 127 INSTALLATION ................................................. 140 TF
SYMPTOM: ....................................................... 127 TRANSFER OIL FILTER ......................................... 141
DIAGNOSTIC PROCEDURE ............................ 127 Removal and Installation ...................................... 141
4WD Warning Lamp Flashes Rapidly .................. 128 REMOVAL ......................................................... 141 E
SYMPTOM: ....................................................... 128 INSTALLATION ................................................. 141
DIAGNOSTIC PROCEDURE ............................ 128 TRANSFER ASSEMBLY ........................................ 143
4WD Warning Lamp Flashes Slowly .................... 129 Removal and Installation ...................................... 143
SYMPTOM: ....................................................... 129 REMOVAL ......................................................... 143 F
DIAGNOSTIC PROCEDURE ............................ 129 INSTALLATION ................................................. 143
Heavy Tight-corner Braking Symptom Occurs ..... 130 Disassembly and Assembly .................................. 144
SYMPTOM: ....................................................... 130 COMPONENTS ................................................. 144 G
DIAGNOSTIC PROCEDURE ............................ 130 DISASSEMBLY ................................................. 146
4WD System Does Not Operate .......................... 131 INSPECTION AFTER DISASSEMBLY .............. 161
SYMPTOM: ....................................................... 131 ASSEMBLY ....................................................... 165 H
DIAGNOSTIC PROCEDURE ............................ 131 SERVICE DATA AND SPECIFICATIONS (SDS) .... 181
TRANSFER CONTROL UNIT ................................. 132 General Specifications .......................................... 181
Removal and Installation ...................................... 132 Inspection and Adjustment ................................... 181
I
REMOVAL ......................................................... 132 CLEARANCE BETWEEN INNER GEAR AND
INSTALLATION ................................................. 132 OUTER GEAR ................................................... 181
FRONT OIL SEAL .................................................. 133 CLUTCH ............................................................ 181
Removal and Installation ...................................... 133 PINION GEAR END PLAY ................................ 181 J
REMOVAL ......................................................... 133 CLEARANCE BETWEEN SHIFT FORK AND
INSTALLATION ................................................. 134 SLEEVE ............................................................ 181
REAR OIL SEAL .................................................... 135 SELECTIVE PARTS .......................................... 181 K
Removal and Installation ...................................... 135
REMOVAL ......................................................... 135
INSTALLATION ................................................. 135
L

Revision: October 2005 TF-3 2005 QX56

 PRECAUTIONS

PRECAUTIONS PFP:00001

Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER” EDS002H3

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 and SB section of this Service Man-
ual.
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 per-
formed by an authorized NISSAN/INFINITI dealer.
● Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
● 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.
Precautions for Transfer Assembly and Transfer Control Unit Replacement EDS002H4

When replacing transfer assembly or transfer control unit, check the 4WD shift indicator lamp as follows.
1. Turn ignition switch “ON”.
2. Check 4WD shift indicator lamp is turned ON for approx. 1 second.
● If OK, the position between transfer assembly and transfer control unit is correct.
● If NG, the position is different between transfer assembly and transfer control unit.
Adjust the position between transfer assembly and transfer control unit. Refer to TF-4, "METHOD FOR
POSITION ADJUSTMENT" .
METHOD FOR POSITION ADJUSTMENT
1. Start engine. Run the engine for at least 10 seconds.
2. Stop vehicle and move A/T selector lever to “N” position with brake pedal depressed. Stay in "N" for at
least 2 seconds.
3. Turn 4WD shift switch to “2WD” position. Stay in "2WD" for at least 2 seconds.
4. Turn ignition switch “OFF”.
5. Start engine.
6. Erase self-diagnosis. Refer to TF-47, "How to Erase Self-diagnostic Results" (with CONSULT-II) or TF-
53, "ERASE SELF-DIAGNOSIS" (without CONSULT-II).
7. Check 4WD shift indicator lamp. Refer to TF-32, "CHECK BEFORE ENGINE IS STARTED" .
If 4WD shift indicator lamp does not indicate "2WD", install new transfer control unit and retry the above
check.
Precautions EDS002H5

● Before connecting or disconnecting the transfer control

unit harness connector, turn ignition switch “OFF” and dis-
connect battery ground cable. Failure to do so may damage
the transfer control unit. Battery voltage is applied to trans-
fer control unit even if ignition switch is turned “OFF”.

SEF289H

Revision: October 2005 TF-4 2005 QX56

 PRECAUTIONS

● When connecting or disconnecting pin connectors into or

from transfer control unit, take care not to damage pin ter- A
minals (bend or break).
When connecting pin connectors make sure that there are
not any bends or breaks on transfer control unit pin termi-
B
nals.

SEF291H

TF
● Before replacing transfer control unit, perform transfer con-
trol unit input/output signal inspection and make sure
transfer control unit functions properly. Refer to TF-36,
E
"Transfer Control Unit Input/Output Signal Reference Val-
ues" .

G
MEF040DB

Service Notice EDS002H6

H
● After overhaul refill the transfer with new transfer fluid.
● Check the fluid level or replace the fluid only with the vehicle parked on level ground.
● During removal or installation, keep inside of transfer clear of dust or dirt. I
● Disassembly should be done in a clean work area.
● Before proceeding with disassembly, thoroughly clean the transfer. It is important to prevent the internal
parts from becoming contaminated by dirt or other foreign matter. J
● Check for the correct installation status prior to removal or disassembly. If matchmarks are required, be
certain they do not interfere with the function of the parts when applied.
● All parts should be carefully cleaned with a general purpose, non-flammable solvent before inspection or K
reassembly.
● Check appearance of the disassembled parts for damage, deformation, and unusual wear. Replace them
with new ones if necessary. L
● Gaskets, seals and O-rings should replaced any time the transfer is disassembled.
● In principle, tighten bolts or nuts gradually in several steps working diagonally from inside to outside. If
tightening sequence is specified, use it. M
● Observe the specified torque when assembling.
● Clean and flush the parts sufficiently and blow-dry them.
● Be careful not to damage sliding surfaces and mating surfaces.
● Use lint-free cloth or towels for wiping parts clean. Common shop rags can leave fibers that could interfere
with the operation of the transfer.
Wiring Diagrams and Trouble Diagnosis EDS002H7

When reading wiring diagrams, refer to the following:

● GI-15, "How to Read Wiring Diagrams".
● PG-4, "POWER SUPPLY ROUTING CIRCUIT".
When performing trouble diagnosis, refer to the following:
● GI-11, "How to Follow Trouble Diagnoses".
● GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident".

Revision: October 2005 TF-5 2005 QX56

 PREPARATION

PREPARATION PFP:00002

Special Service Tools EDS002HZ

The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number Description
(Kent-Moore No.)
Tool name
KV40104000 ● Removing self-lock nut
( — ) ● Installing self-lock nut
Flange wrench
a: 85 mm (3.35 in)
b: 65 mm (2.56 in)

NT659

ST33290001 ● Removing front oil seal

(J-34286) ● Removing rear oil seal
Puller
● Removing metal bushing

ZZA0601D

KV38100500 ● Installing front oil seal

( — ) a: 80 mm (3.15 in) dia.
Drift b: 60 mm (2.36 in) dia.

ZZA0811D

ST30720000 ● Installing rear oil seal

(J-25405) ● Installing mainshaft front bearing and oil
Drift seal
a: 77 mm (3.03 in) dia.
b: 55.5 mm (2.185 in) dia.

ZZA0811D

KV40105310 ● Installing dust cover

( — ) a: 89 mm (3.50 in) dia.
Drift b: 80.7 mm (3.17 in) dia.

ZZA1003D

ST22360002 ● Installing side oil seal

(J-25679-01) a: 23 mm (0.91 in) dia.
Drift b: 32 mm (1.26 in) dia.

ZZA1091D

ST35300000 ● Removing sun gear assembly and planetary

( — ) carrier assembly
Drift ● Removing carrier bearing
● Installing metal bushing
a: 59 mm (2.32 in) dia.
b: 45 mm (1.77 in) dia.
NT073

Revision: October 2005 TF-6 2005 QX56

 PREPARATION

Tool number Description

(Kent-Moore No.) A
Tool name
ST33200000 ● Removing mainshaft front bearing
(J-26082) ● Installing sun gear assembly and planetary B
Drift carrier assembly
● Installing mainshaft front bearing and oil
seal
C
a: 74.5 mm (2.933 in) dia.
NT661 b: 62.5 mm (2.461 in) dia.
ST30031000 ● Removing carrier bearing TF
( — ) ● Removing front drive shaft front bearing
Puller
● Removing front drive shaft rear bearing
a: 90 mm (3.54 in) dia. E
b: 50 mm (1.97 in) dia.

NT411

ST33710000 ● Removing needle bearing F

( — ) ● Removing metal bushing
Drift
a: 24 mm (0.94 in) dia.
b: 89 mm (3.5 in) G
c: 30 mm (1.18 in) dia.

ZZA1057D H
ST35325000 ● Removing metal bushing
( — ) a: 215 mm (8.46 in)
Drift bar b: 25 mm (0.98 in) dia. I
c: M12 × 1.5P

J
NT663

ST33052000 ● Removing front drive shaft front bearing

( — ) ● Removing front drive shaft rear bearing
Adapter K
● Installing mainshaft
a: 28 mm (1.10 in) dia.
b: 22 mm (0.87 in) dia.
L
NT431

ST22452000 ● Removing press flange snap ring

(J-34335) M
● Installing press flange snap ring
Drift
a: 45 mm (1.77 in) dia.
b: 36 mm (1.42 in) dia.
c: 400 mm (15.76 in) dia.

NT117

ST30911000 ● Removing press flange snap ring

( — ) ● Installing press flange snap ring
Puller
● Installing mainshaft
● Installing carrier bearing
a: 98 mm (3.86 in) dia.
b: 40.5 mm (1.594 in) dia.
NT664

Revision: October 2005 TF-7 2005 QX56

 PREPARATION

Tool number Description

(Kent-Moore No.)
Tool name
KV31103300 ● Removing press flange snap ring
( — ) ● Installing press flange snap ring
Drift
● Installing carrier bearing
a: 76.3 mm (3.004 in) dia.
b: 130 mm (5.12 in)

NT668

KV38100300 ● Removing mainshaft rear bearing

(J-25523) a: 54 mm (2.13 in) dia.
Drift b: 46 mm (1.81 in) dia.
c: 32 mm (1.26 in) dia.

ZZA1046D

ST15310000 ● Installing mainshaft rear bearing

(J-25640-B) a: 96 mm (3.78 in) dia.
Drift b: 84 mm (3.31 in) dia.

ZZA0908D

KV40100621 ● Installing front drive shaft front bearing

(J-25273) ● Installing front drive shaft rear bearing
Drift
a: 76 mm (2.99 in) dia.
b: 69 mm (2.72 in) dia.

NT086

ST30032000 ● Installing front drive shaft front bearing

(J-26010-01) ● Installing front drive shaft rear bearing
Base
a: 38 mm (1.50 in) dia.
b: 80 mm (3.15 in) dia.

NT660

ST3322000 ● Installing needle bearing

( — ) a: 37 mm (1.46 in) dia.
Drift b: 31 mm (1.22 in) dia.
b: 22 mm (0.87 in) dia.

ZZA1046D

Revision: October 2005 TF-8 2005 QX56

 PREPARATION

Commercial Service Tools EDS002I0

A
Tool name Description
Puller ● Removing companion flange
B

C
NT077

Pin punch ● Removing retainer pin

TF
● Installing retainer pin
a: 6 mm (0.24 in) dia.

NT410

Power tool ● Removing transfer case assembly F

PBIC0190E
H

Revision: October 2005 TF-9 2005 QX56

 NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING

NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING PFP:00003

NVH Troubleshooting Chart EDS002I1

Use the chart below to help you find the cause of the symptom. The numbers indicate the order of the inspec-
tion. If necessary, repair or replace these parts.

TF-144

TF-161

TF-161

TF-161
TF-11
Reference page

TRANSFER FLUID (Level too high)

SHIFT FORK (Worn or damaged)

TRANSFER FLUID (Level low)

BEARING (Worn or damaged)

OIL SEAL (Worn or damaged)
LIQUID GASKET (Damaged)

O-RING (Worn or damaged)

TRANSFER FLUID (Wrong)

GEAR (Worn or damaged)

SUSPECTED PARTS
(Possible cause)

Noise 1 2 3 3
Symptom Transfer fluid leakage 3 1 2 2 2
Hard to shift or will not shift 1 1 2

Revision: October 2005 TF-10 2005 QX56

 TRANSFER FLUID

TRANSFER FLUID PFP:31001

A
Replacement EDS002I2

DRAINING
1. Stop the engine.
B
2. Remove the drain plug and gasket to drain the transfer fluid as
shown.
3. Install the new gasket on the drain plug and install the drain plug
C
in the transfer. Tighten the drain plug to specification.
Drain plug : Refer to TF-144, "COMPONENTS" .
CAUTION: TF
Do not reuse the gasket.

E
SMA444B

FILLING
1. Remove the filler plug and gasket. Fill with new specified fluid F
until the fluid level reaches the specified limit near the filler plug
mounting hole as shown.
Fluid capacity and grade : Refer to MA-11, "Fluids G
and Lubricants" .
CAUTION:
Carefully fill the transfer with fluid. Filling should take H
approximately three minutes.
2. Leave the vehicle for three minutes and then check the fluid
level again as shown. SMA439B I
3. Install the new gasket on the filler plug and install the filler plug
in the transfer. Tighten the filler plug to specification.
Filler plug : Refer to TF-144, "COMPONENTS" . J

CAUTION:
Do not reuse the gasket.
K
Inspection EDS002I3

FLUID LEAKAGE AND FLUID LEVEL

1. Check for any fluid leaks from the transfer assembly or around it and correct as necessary. L
2. Remove the filler plug to check the fluid level at the filler plug
mounting hole as shown.
CAUTION: M
Do not start the engine while checking the fluid level.
3. Install the new gasket on the filler plug and install the filler plug
in the transfer. Tighten the filler plug to specification.
Filler plug : Refer to TF-144, "COMPONENTS" .
CAUTION:
Do not reuse the gasket.
SMA439B

Revision: October 2005 TF-11 2005 QX56

 ALL-MODE 4WD SYSTEM

ALL-MODE 4WD SYSTEM PFP:00000

Cross-section View EDS002H8

WDIA0202E

1. Center case 2. Front case 3. Internal gear

4. Planetary carrier assembly 5. Sun gear assembly 6. Main shaft
7. L-H sleeve 8. L-H fork 9. Shift rod
10. 2-4 sleeve 11. 2-4 fork 12. Drive chain
13. Front drive shaft 14. Control valve assembly 15. Transfer motor
16. Rear case 17. Clutch piston 18. Press flange
19. Multiple disc clutch 20. Clutch hub assembly 21. Clutch drum assembly

Revision: October 2005 TF-12 2005 QX56

 ALL-MODE 4WD SYSTEM

Power Transfer EDS002H9

POWER TRANSFER DIAGRAM A

TF

LDIA0053E

1. Center case 2. Chain 3. Multiple disc clutch M

4. Rear case 5. Mainshaft 6. Clutch hub assembly
7. Sub oil pump 8. Transfer motor 9. Control valve
10. Front drive shaft 11. Drain plug 12. 2-4 sleeve
13. Sun gear assembly 14. L-H sleeve 15. Planetary carrier assembly
16. Internal gear 17. Front case

Revision: October 2005 TF-13 2005 QX56

 ALL-MODE 4WD SYSTEM

POWER TRANSFER FLOW

WDIA0201E

Revision: October 2005 TF-14 2005 QX56

 ALL-MODE 4WD SYSTEM

System Description EDS002HA

CONTROL SYSTEM A

TF

WDIA0162E

Revision: October 2005 TF-15 2005 QX56

 ALL-MODE 4WD SYSTEM

ALL-MODE 4WD Transfer Basic Control

LDIA0055E

Hydraulic Control Circuits

WDIA0163E

TRANSFER MOTOR
● The transfer motor drives the sub-oil pump to provide proper lubrication and oil pressure control when the
vehicle is at standstill, during low-speed operations or is being driven in reverse.
● The main oil pump is operated by the driving force of the mainshaft. In other words, sufficient oil pressure
buildup does not occur when the vehicle is at standstill or during low-speed operations. While the vehicle
is being driven in reverse, the main oil pump rotates in the reverse direction. Therefore the main oil pump
does not discharge oil pressure. During any of the above vehicle operations, the transfer motor drives the
sub-oil pump to compensate for insufficient oil pressure.
● The transfer motor operates as follows.
– The motor relay turns OFF in the 2WD mode.
– The motor relay operates as described in the table below in modes other than the 2WD mode.

Revision: October 2005 TF-16 2005 QX56

 ALL-MODE 4WD SYSTEM

Table 1
PNP switch “R” position VFF (Vehicle speed) A/T position Motor relay drive command
A

ON — R ON
Positions other than the “P” or
0 ON B
“N” positions
“P” or “N” position (See Table
— —
2.)
OFF C
0 < VFF ≤ 50 km/h (31 MPH) — ON
50 km/h (31 MPH) < VFF < 55
— HOLD
km/h (34 MPH)
TF
55 km/h (34 MPH) ≤ VFF — OFF

Table 2
E
Throttle position
A/T position N-4L SW 4WD mode
0 - 0.07/8 0.07/8 - 1/8 1/8 - MAX
LOCK (4H) ON ON ON F
OFF Positions other than
N the LOCK position OFF* HOLD ON
(2WD or AUTO)
G
ON — OFF* HOLD ON
P — — OFF* HOLD ON
*: After 2.5 seconds have elapsed. H
● 4WD shift switch, PNP switch, Neutral-4LO switch, vehicle speed sensor and throttle position sensor are
used in conjunction with the transfer motor.
I
WAIT DETECTION SWITCH
● The wait detection switch operates when there is “circulating” torque produced in the propeller shaft
(L→H) or when there is a phase difference between 2-4 sleeve and clutch drum (H→L). After the release
J
of the “circulating” torque, the wait detection switch helps provide the 4WD lock gear (clutch drum) shifts.
A difference may occur between the operation of the 4WD shift switch and actual drive mode. At this
point, the wait detection switch senses an actual drive mode.
● The wait detection switch operates as follows. K
– 4WD lock gear (clutch drum) locked: ON
– 4WD lock gear (clutch drum) released: OFF
L
● The wait detection switch senses an actual drive mode and the 4WD shift indicator lamp indicates the
vehicle drive mode.
NEUTRAL-4LO SWITCH M
The neutral-4LO switch detects that transfer gear is in neutral or 4LO (or shifting from neutral to 4LO) condi-
tion by L-H shift fork position.
ATP SWITCH
ATP switch detects if transfer gear is in a neutral condition by L-H shift fork position.
NOTE:
Transfer gear may be in a neutral condition in 4H-4LO.
2-4WD SHIFT SOLENOID VALVE
The 2-4WD shift solenoid valve operates to apply oil pressure to the wet-multiplate clutch, depending on the
drive mode. The driving force is transmitted to the front wheels through the clutch so the vehicle is set in the
4WD mode. Setting the vehicle in the 2WD mode requires no pressure buildup. In other words, pressure force
applied to the wet-multiplate clutch becomes zero.
CLUTCH PRESSURE SOLENOID VALVE
The clutch pressure solenoid valve distributes torque (front and rear) in AUTO mode.

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 ALL-MODE 4WD SYSTEM

LINE PRESSURE SWITCH

● With the transfer system design, control of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.
● The line pressure switch determines whether or not adequate line pressure has built up under different
operating conditions.
● The line pressure switch turns ON when line pressure is produced.
● The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH
● The clutch pressure switch determines whether or not adequate clutch pressure has built up under differ-
ent operating conditions.
● The clutch pressure switch turns ON when clutch pressure is produced.
● The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
TRANSFER FLUID TEMPERATURE SENSOR
The transfer temperature sensor detects the transfer fluid temperature and sends a signal to the transfer con-
trol unit.
TRANSFER CONTROL UNIT
● Transfer control unit controls transfer control device by input signals of each sensor and each switch.
● Self-diagnosis can be done.
TRANSFER CONTROL DEVICE
The transfer control device changes the state of transfer assembly between 2WD, AUTO, 4H⇔4LO with the
2WD, AUTO, 4H and 4LO signals of 4WD shift switch.
NOTE:
● To shift between 4H⇔4LO, stop the vehicle, depress the brake pedal and shift the transmission selector
to the "N" position. Depress and turn the 4WD shift switch. The shift switch will not shift to the desired
mode if the transmission is not in "N" or the vehicle is moving. The 4LO indicator lamp will be lit when the
4LO is engaged.
● Actuator motor and actuator position switch are integrated.
4WD SHIFT SWITCH AND INDICATOR LAMP
4WD Shift Switch
The 4WD shift switch allows selection from 2WD, AUTO, 4H or 4LO.
4WD Shift Indicator Lamp
● Displays driving conditions selected by 4WD shift switch with 2WD, AUTO and 4H indicators while engine
is running. (When 4WD warning lamp is turned on, all 4WD shift indicator lamps are turned off.)
● Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4LO Indicator Lamp
● Displays 4LO condition while engine is running. 4LO indicator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)
● Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.

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 ALL-MODE 4WD SYSTEM

4WD WARNING LAMP

Turns ON or FLASH when there is a malfunction in 4WD system. A
Also turns ON when ignition switch is turned ON, for purpose of lamp check. Turns OFF for approximately 1
second after the engine starts if system is normal.
4WD Warning Lamp Indication B

Condition Content 4WD warning lamp

During self-diagnosis Indicates the malfunction position by number of flickers. Flickers at malfunction mode. C
Checks the lamp by turning ON during engine starting. After
Lamp check* ON
engine starts, it turns OFF if there are no malfunctions.
Turns ON to indicate malfunction. When ignition switch is TF
Malfunction in 4WD system* ON
turned to “OFF” or the malfunction is corrected, it turns OFF.
When vehicle is driven with different Flickers once every 2 seconds. Flickers once every 2 sec-
diameters of front and rear tires Turns OFF when ignition switch is “OFF”. onds.
E
When fluid temperature is high or fluid temperature sensor cir-
High fluid temperature in transfer unit cuit is shorted, it flickers twice every second. Flickers twice a second.
It turns OFF when fluid temperature becomes normal.
F
Other than above (System is nor-
Lamp is OFF. OFF
mal.)
*: When 4WD warning lamp is ON, all the 4WD shift indicator lamps turn OFF.
G
ATP WARNING LAMP
Even if A/T selector lever is in “P” position, vehicle may move because A/T parking mechanism does not oper-
ate when transfer is under neutral condition. ATP warning lamp is turned on so as to indicate this condition to H
the driver.
System Diagram EDS002HB

WDIA0164E

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 ALL-MODE 4WD SYSTEM

COMPONENTS FUNCTION
Component parts Function
Transfer control unit Controls transfer control device and control valves.
Transfer control device Actuator motor and actuator position switch are integrated so as to switch driving types.
2-4WD shift solenoid valve Controls oil pressure and allows selection between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque (front and rear).
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sen-
Detects transfer fluid temperature.
sor
Wait detection switch Detects whether or not 4WD lock gear is locked.
Neutral-4LO switch Detects that transfer is under neutral-4LO condition (or shifting through neutral).
ATP switch Detects that transfer is under neutral condition.
4WD shift switch Allows selection from 2WD, AUTO, 4H or 4LO.
● Illuminates if malfunction is detected in electrical system of 4WD system.
4WD warning lamp ● There is 1 blink every 2 seconds if rotation difference of front wheels and rear wheels is large.
● There is 2 blinks every 1 second if high transfer fluid temperature is detected.
Indicates that A/T parking mechanism does not operate when A/T selector lever is in “P” position
ATP warning lamp
and transfer is under neutral condition.
4WD shift indicator lamp Displays driving condition selected by 4WD shift switch.
4LO indicator lamp Displays 4LO condition.
ABS actuator and electric unit
Transmits vehicle speed signal via CAN communication to transfer control unit.
(control unit)
Transmits the following signals via CAN communication to transfer control unit.
TCM ● Output shaft revolution signal
● A/T position indicator signal (PNP switch signal)
Transmits the following signals via CAN communication to transfer control unit.
ECM ● Engine speed signal
● Accelerator pedal position signal

CAN Communication EDS002HC

SYSTEM DESCRIPTION
Refer to LAN-5, "CAN COMMUNICATION" .

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 TROUBLE DIAGNOSIS

TROUBLE DIAGNOSIS PFP:00004

A
How to Perform Trouble Diagnosis EDS002HD

BASIC CONCEPT
● To perform trouble diagnosis, it is the most important to have understanding about vehicle systems (con- B
trol and mechanism) thoroughly.
● It is also important to clarify customer complaints before inspec-
tion.
First of all, reproduce symptoms, and understand them fully. C
Ask customer about his/her complaints carefully. In some cases,
it will be necessary to check symptoms by driving vehicle with
customer. TF
CAUTION:
Customers are not professional. It is dangerous to make an
easy guess like "maybe the customer means that...," or E
"maybe the customer mentions this symptom".
SEF233G

F
● It is essential to check symptoms right from the beginning in
order to repair malfunctions completely.
For intermittent malfunctions, reproduce symptoms based on
interview with customer and past examples. Do not perform G
inspection on ad hoc basis. Most intermittent malfunctions are
caused by poor contacts. In this case, it will be effective to shake
suspected harness or connector by hand. When repairing with- H
out any symptom diagnosis, you cannot judge if malfunctions
have actually been eliminated.
● After completing diagnosis, always erase diagnostic memory. I
Refer to TF-53, "ERASE SELF-DIAGNOSIS" . SEF234G

● For intermittent malfunctions, move harness or harness connec-

tor by hand. Then check for poor contact or reproduced open circuit. J

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 TROUBLE DIAGNOSIS

Location of Electrical Parts EDS002HE

WDIA0220E

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 TROUBLE DIAGNOSIS

Circuit Diagram EDS002HF

TF

WDWA0015E

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 TROUBLE DIAGNOSIS

Wiring Diagram — T/F — EDS002HG

WDWA0016E

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 TROUBLE DIAGNOSIS

TF

WDWA0017E

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 TROUBLE DIAGNOSIS

WDWA0018E

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 TROUBLE DIAGNOSIS

TF

WDWA0019E

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 TROUBLE DIAGNOSIS

WDWA0020E

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 TROUBLE DIAGNOSIS

TF

WDWA0021E

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 TROUBLE DIAGNOSIS

WDWA0022E

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 TROUBLE DIAGNOSIS

TF

WDWA0023E

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 TROUBLE DIAGNOSIS

Inspections Before Trouble Diagnosis EDS002HH

TRANSFER FLUID CHECK

Check fluid for leaks and fluid level. Refer to TF-11, "Inspection" .
PREPARATION FOR ROAD TEST
● The purpose of the test is to determine overall performance of
transfer and analyze causes of problems.
● When a malfunction is found in any part of transfer, perform the
road test to locate the malfunction area and repair the malfunc-
tion parts.
● The road test consists of the following three parts.
– Check before engine is started. Refer to TF-32, "CHECK
BEFORE ENGINE IS STARTED" .
– Check at idle. Refer to TF-32, "CHECK AT IDLE" .
– Cruise test. Refer to TF-34, "CRUISE TEST" . SMT089D

CHECK BEFORE ENGINE IS STARTED

1. CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface.
2. Turn ignition switch to “OFF” position.
3. Move A/T selector lever to “P” position.
4. Set 4WD shift switch to “2WD” position.
5. Turn ignition switch to “ON” position. (Do not start engine.)
Does 4WD shift indicator lamp turn ON for approximately 1 second?
YES >> GO TO 2.
NO >> Go to TF-117, "4WD Shift Indicator Lamp and 4LO Indicator Lamp Do Not Turn ON" .

2. CHECK 4WD WARNING LAMP

1. Turn ignition switch to “OFF” position.
2. Move A/T selector lever to “P” position.
3. Set 4WD shift switch to “2WD” position.
4. Turn ignition switch to “ON” position. (Do not start engine.)
Does 4WD warning lamp turn ON?
YES >> GO TO TF-32, "CHECK AT IDLE" .
NO >> GO TO TF-121, "4WD Warning Lamp Does Not Turn ON" .
CHECK AT IDLE
1. CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface and engage the parking brake.
2. Turn ignition switch to “OFF” position.
3. Move A/T selector lever to “P” position.
4. Set 4WD shift switch to “2WD” position.
5. Start engine.
Does 4WD shift indicator lamp turn ON?
YES >> GO TO 3.
NO >> GO TO 2.

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 TROUBLE DIAGNOSIS

2. CHECK 4WD WARNING LAMP A

Check 4WD warning lamp state?
Is 4WD warning lamp turned ON?
YES >> Perform the self-diagnosis. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CON- B
SULT-II)" (with CONSULT-II) or TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITHOUT CON-
SULT-II)" (without CONSULT-II).
NO >> Go to TF-123, "4WD Shift Indicator Lamp or 4LO Indicator Lamp Does Not Change" . C

3. CHECK 4WD SHIFT INDICATOR AND 4LO INDICATOR OPERATION

1. Brake pedal depressed. TF
2. Move A/T selector lever to “N” position.
3. Set 4WD shift switch to “2WD”, “AUTO”, “4H”, “4LO”, “4H”,
“AUTO” and “2WD” in order. (Stay at each switch position for at E
least 1 second.)
Do 4WD shift indicator and 4LO indicator lamps change properly?
Does buzzer sound? F
YES >> GO TO 4.
NO >> GO TO TF-123, "4WD Shift Indicator Lamp or 4LO Indi-
cator Lamp Does Not Change" . G

WDIA0136E

K
4. CHECK ATP WARNING LAMP
1. Move the A/T selector lever to “P” position.
2. Set 4WD shift switch from “4HI” to "4LO". L
While switching from "4HI" to "4LO", does 4WD shift indicator lamp turn OFF and ATP warning lamp turn ON?
YES >> GO TO TF-125, "ATP Warning Lamp Turns ON" .
NO >> GO TO 5. M

5. CHECK "WAIT" FUNCTION

1. Set 4WD shift switch from “4LO” to "4H".
2. Check 4LO indicator lamp state.
NOTE:
While “wait” function is operating, 4LO indicator lamp flashes.
Does 4LO indicator lamp flicker?
YES >> GO TO TF-127, "4LO Indicator Lamp Repeats Flashing" .
NO >> TF-34, "CRUISE TEST".

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 TROUBLE DIAGNOSIS

CRUISE TEST

1. CHECK INPUT SIGNAL

1. Warm up engine to normal operating temperature.
2. Park vehicle on flat surface.
3. Move A/T selector lever to “P” position.
4. Set 4WD shift switch to “AUTO” position.
5. Start engine.
6. Drive vehicle for at least 30 seconds at a speed higher than 20 km/h (12 MPH).
Check 4WD warning lamp turned ON?
On steady>>Perform the self-diagnosis. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CON-
SULT-II)" (with CONSULT-II) or TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITHOUT CON-
SULT-II)" (without CONSULT-II).
Flash rapidly>>GO TO TF-128, "4WD Warning Lamp Flashes Rapidly" .
Flash slowly>>GO TO TF-129, "4WD Warning Lamp Flashes Slowly" .
NO >> GO TO 2.

2. CHECK TIGHT CORNER BRAKING SYMPTOM (1)

1. Set 4WD shift switch to “AUTO” position.
2. Drive vehicle at speed lower than 20 km/h (12 MPH) with steering wheel fully turned.
Does tight corner braking symptom occur?
YES >> GO TO TF-130, "Heavy Tight-corner Braking Symptom Occurs" .
NO >> GO TO 3.

3. CHECK TIGHT CORNER BRAKING SYMPTOM (2)

1. Set 4WD shift switch to “4HI” position.
2. Drive vehicle at speed lower than 20 km/h (12 MPH) with steering wheel fully turned.
Does tight corner braking symptom occur?
YES >> Inspection End.
NO >> GO TO TF-131, "4WD System Does Not Operate" .
Trouble Diagnosis Chart for Symptoms EDS002HI

If 4WD warning lamp turns ON, perform self-diagnosis. Refer to TF-50, "Self-diagnostic Procedure" .
Symptom Condition Check item Reference page
Power supply and ground for transfer
4WD shift indicator lamp and 4LO indicator
control unit
lamp do not turn ON
Ignition switch: ON TF-117
(4WD shift indicator lamp and 4LO indicator Transfer shut off relay
lamp check)
Combination meter
Power supply and ground for transfer
control unit
4WD warning lamp does not turn ON
Ignition switch: ON TF-121
(4WD warning lamp check) Transfer shut off relay
Combination meter

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 TROUBLE DIAGNOSIS

Symptom Condition Check item Reference page

A
4WD shift switch
Wait detection switch
Neutral-4LO switch B
ATP switch
4WD shift indicator lamp or 4LO indicator
Engine running 2-4WD solenoid TF-123
lamp does not change
Transfer control device C
Actuator motor
Actuator position switch
TF
Transfer inner parts
CAN communication line
4WD shift switch E
PNP switch signal
ATP warning lamp turns ON Engine running TF-125
ATP switch
F
Combination meter
Transfer inner parts
Wait detection switch G
4LO indicator lamp repeats flashing Engine running Neutral-4LO switch TF-127
Transfer inner parts
H
Transfer fluid temperature
4WD warning lamp flashes rapidly (2 times/
While driving Tire size is different between front and TF-128
second)
rear of vehicle
I
Tire size is different between front and
rear of vehicle.
4WD warning lamp flashes slowly
While driving TF-129
(1 time/2 seconds) Transfer fluid temperature
J
Clutch pressure switch
CAN communication line
● While driving
4WD shift switch K
● AUTO mode
Heavy tight-corner braking symptom occurs
● Steering wheel is Accelerator pedal position signal TF-130
(See NOTE.)
turned fully to either Clutch pressure solenoid
side L
Transfer inner parts
4WD shift switch
4WD system does not operate While driving Clutch pressure switch TF-131 M
Transfer inner parts

NOTE:
● Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not
a malfunction.
● Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is "4H" or "4LO", steering wheel is turned fully to either side.

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 TROUBLE DIAGNOSIS

Transfer Control Unit Input/Output Signal Reference Values EDS002HJ

TRANSFER CONTROL UNIT INSPECTION TABLE

Specifications with CONSULT-II
Monitored item [Unit] Content Condition Display value
Vehicle stopped 0 km/h (0 MPH)
Approximately
VHCL/S SEN·FR [km/h] Wheel speed (Front Vehicle running equal to the indi-
or [mph] wheel) CAUTION: cation on speed-
Check air pressure of tire under standard condition. ometer (Inside of
±10%)
Vehicle stopped 0 km/h (0 MPH)
Approximately
VHCL/S SEN·RR [km/h] Wheel speed (Rear Vehicle running equal to the indi-
or [mph] wheel) CAUTION: cation on speed-
Check air pressure of tire under standard condition. ometer (Inside of
±10%)
Engine stopped
0 rpm
(Engine speed: Less than 400 rpm)

ENGINE SPEED [rpm] Engine speed Approximately

Engine running equal to the indi-
(Engine speed: 400 rpm or more) cation on tachom-
eter
Accelerator pedal posi- Accelerator pedal: Release Approx. 0.5V
THRTL POS SEN [V] tion (APP) sensor signal
voltage Accelerator pedal: Fully depressed Approx. 4.0V

Transfer fluid tempera-

FLUID TEMP SE [V] Transfer fluid temperature approx. 20 - 80°C (68 - 176°F) Approx. 1.1 - 0.3V
ture signal voltage
Power supply voltage for
BATTERY VOLT [V] Ignition switch: ON Battery voltage
transfer control unit

Input condition from 4WD shift switch: 2WD ON

2WD SWITCH [ON/OFF]
4WD shift switch 4WD shift switch: AUTO, 4H or 4LO OFF

AUTO SWITCH [ON/ Input condition from 4WD shift switch: AUTO ON
OFF] 4WD shift switch 4WD shift switch: 2WD, 4H or 4LO OFF

LOCK SWITCH [ON/ Input condition from 4WD shift switch: 4H ON

OFF] 4WD shift switch 4WD shift switch: 2WD, AUTO or 4LO OFF

Input condition from 4WD shift switch: 4LO ON

4L SWITCH [ON/OFF]
4WD shift switch 4WD shift switch: 2WD, AUTO or 4H OFF
4WD shift switch: 2WD,
OFF
AUTO or 4H
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (While actuator OFF → ON
N POSI SW TF [ON/ Condition of neutral-4LO
OFF] switch ● A/T selector lever “N” posi- motor is operating.)
tion 4WD shift switch: 4LO to
● Brake pedal depressed 4H (While actuator motor ON → OFF
is operating.)
4WD shift switch: 4LO ON

● Vehicle stopped 4WD shift switch

: 4H to 4LO or 4LO to 4H
● Engine running ON
ATP SWITCH [ON/OFF] Condition of ATP switch (While actuator motor is
● A/T selector lever “N” operating.)
● Brake pedal depressed Except the above OFF

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 TROUBLE DIAGNOSIS

Monitored item [Unit] Content Condition Display value

A
4WD shift switch: 2WD,
OFF
AUTO or 4H
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (While actuator OFF → ON B
WAIT DETCT SW [ON/ Condition of wait detec- motor is operating.)
OFF] tion switch ● A/T selector lever “N” posi-
tion 4WD shift switch: 4LO to
● Brake pedal depressed 4H (While actuator motor OFF → ON C
is operating.)
4WD shift switch: 4LO ON
● A/T selector lever “D” position TF
ON
● 4WD shift switch: 2WD, AUTO or 4H
● Except the above ● Ignition switch: ON
LINE PRES SW [ON/ Condition of line pres- E
● The vehicle has been left ● A/T selector lever: “P”
OFF] sure switch
at room temperature for 5 or "N" position OFF
minutes and more with
ignition switch in “OFF” ● 4WD shift switch: other
than AUTO F
position.
● Vehicle stopped
● Engine running
G
● A/T selector lever “D” position ON
● 4WD shift switch: AUTO or 4H (“Wait” function is not
CL PRES SW [ON / Condition of clutch pres- operating.)
OFF] sure switch H
● Vehicle stopped
● Engine running
OFF
● 4WD shift switch: 2WD (“Wait” function is not operat-
I
ing.)
● Vehicle stopped A/T selector lever posi-
N POSI SW AT [ON/ Input condition from A/T ON
● Engine running tion: N
OFF] PNP switch J
● Brake pedal depressed Except the above OFF
● Vehicle stopped A/T selector lever posi-
R POSI SW AT [ON/ Input condition from A/T ON
● Engine running tion: R
OFF] PNP switch K
● Brake pedal depressed Except the above OFF
● Vehicle stopped A/T selector lever posi-
P POSI SW AT [ON/ Input condition from A/T ON
● Engine running tion: P L
OFF] PNP switch
● Brake pedal depressed Except the above OFF

ABS OPER SW [ON/ Condition of ABS operat- ABS is operating. ON

OFF] ing M
ABS is not operating. OFF

VDC OPER SW [ON/ Condition of VDC operat- VDC is operating. ON

OFF] ing VDC is not operating. OFF

TCS OPER SW [ON/ Condition of TCS operat- TCS is operating. ON

OFF] ing TCS is not operating. OFF
Condition of throttle When depressing accelerator pedal
THROTTLE POSI [0.0/8] 0.0/8 - 8.0/8
opening (Value rises gradually in response to throttle position.)
● Vehicle stopped 4WD shift switch: 2WD 2WD
Control status of 4WD ● Engine running 4WD shift switch: AUTO AUTO
4WD MODE [AUTO/ (Output condition of
LOCK/2WD/4L] 4WD shift indicator lamp ● A/T selector lever “N” posi- 4WD shift switch: 4H LOCK
and 4LO indicator lamp) tion
● Brake pedal depressed 4WD shift switch: 4LO 4L

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 TROUBLE DIAGNOSIS

Monitored item [Unit] Content Condition Display value

Vehicle stopped 0 km/h (0 MPH)
Approximately
VHCL/S COMP [km/h] or Vehicle running equal to the indi-
Vehicle speed
[mph] CAUTION: cation on speed-
Check air pressure of tire under standard condition. ometer (Inside of
±10%)
4WD shift switch: 2WD 0 kg-m
● Vehicle stopped
39 - 1,353 N·m
● Engine running 4WD shift switch: AUTO (4 - 138 kg-m, 29 -
Condition of control
COMP CL TORQ [kgm] ● A/T selector lever “N” posi- 998 ft-lb)
torque
tion 1,353 N·m
4WD shift switch: 4H or
● Brake pedal depressed (138 kg-m, 998 ft-
4LO
lb)
● Vehicle stopped 4WD shift switch: 2WD 4%
● Engine running 4WD shift switch: AUTO 96 - 4%
Condition of clutch pres-
DUTY SOLENOID [%] ● A/T selector lever “N” posi-
sure solenoid
tion 4WD shift switch: 4H or
4%
4LO
● Brake pedal depressed
4WD shift switch: 2WD OFF
4WD shift switch: AUTO

● Vehicle stopped 4WD shift switch: 4H ON

● Engine running 4WD shift switch: 4LO

Condition of 2-4WD shift
2-4WD SOL [ON/OFF] ● A/T selector lever “N” posi- 4WD shift switch: AUTO
solenoid valve
tion (“Wait” function is operat- OFF
● Brake pedal depressed ing.)
4WD shift switch: 4H
(“Wait” function is operat- OFF
ing.)
4WD shift switch: 2WD OFF
4WD shift switch: AUTO

● Vehicle stopped 4WD shift switch: 4H ON

● Engine running 4WD shift switch: 4LO

2-4WD SOL MON [ON/ Check signal for transfer
OFF] control unit signal output ● A/T selector lever “N” posi- 4WD shift switch: AUTO
tion (“Wait” function is operat- OFF
● Brake pedal depressed ing.)
4WD shift switch: 4H
(“Wait” function is operat- OFF
ing.)
4WD shift switch: 2WD OFF
OFF
4WD shift switch: AUTO
("ON" for approx. 2
or 4LO (A/T selector lever
sec. after shifting
“P” or “N” position)
to “P” and “N”.)
● Accelerator pedal 4WD shift switch: AUTO
depressed or 4LO (Except for A/T
ON
MOTOR RELAY [ON/ Condition of transfer ● Vehicle stopped selector lever “P” or “N”
OFF] motor relay position)
● Engine running
OFF
● Brake pedal depressed 4WD shift switch: 4H (A/T
("ON" for approx. 2
selector lever “P” posi-
sec. after shifting
tion)
to “P”.)
4WD shift switch: 4H
(Except for A/T selector ON
lever “P” position)

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 TROUBLE DIAGNOSIS

Monitored item [Unit] Content Condition Display value

A
4WD shift switch: 2WD OFF
OFF
4WD shift switch: AUTO
("ON" for approx. 2
or 4LO (A/T selector lever B
sec. after shifting
“P” or “N” position)
to “P” and “N”.)
● Accelerator pedal 4WD shift switch: AUTO
depressed or 4LO (Except for A/T
ON C
MOTOR RELAY MON Check signal for transfer ● Vehicle stopped selector lever “P” or “N”
[ON/OFF] control unit signal output position)
● Engine running
OFF TF
● Brake pedal depressed 4WD shift switch: 4H (A/T
("ON" for approx. 2
selector lever “P” posi-
sec. after shifting
tion)
to “P”.)
4WD shift switch: 4H E
(Except for A/T selector ON
lever “P” position)

4WD FAIL LAMP [ON/ Condition of 4WD warn- 4WD warning lamp: ON ON F
OFF] ing lamp 4WD warning lamp: OFF OFF
Condition of 4WD shift 2WD indicator lamp of 4WD shift indicator lamp: OFF OFF
2WD IND [ON/OFF] indicator lamp (2WD G
indicator lamp) 2WD indicator lamp of 4WD shift indicator lamp: ON ON

Condition of 4WD shift AUTO indicator lamp of 4WD shift indicator lamp: OFF OFF
AUTO IND [ON/OFF] indicator lamp (AUTO H
indicator lamp) AUTO indicator lamp of 4WD shift indicator lamp: ON ON

Condition of 4WD shift Lock indicator lamp of 4WD shift indicator lamp: OFF OFF
LOCK IND [ON/OFF] indicator lamp (Lock indi-
Lock indicator lamp of 4WD shift indicator lamp: ON ON I
cator lamp)

Condition of 4LO indica- 4LO indicator lamp: OFF OFF

4L IND [ON/OFF]
tor lamp condition 4LO indicator lamp: ON ON J
Condition of ATP indica- ATP indicator lamp: ON ON
ATP IND [ON/OFF]
tor lamp ATP indicator lamp: OFF OFF
● Vehicle stopped 4WD shift switch: 4LO ON K
Condition of actuator ● Engine running
SHIFT POS SW1 [ON/
position switch 1 ● A/T selector lever “N” posi- 4WD shift switch: 2WD,
OFF] OFF
(Low) tion AUTO or 4H L
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4H,
ON M
● Engine running AUTO or 2WD
Condition of actuator
SHIFT POS SW2 [ON/
position switch 2 ● A/T selector lever “N” posi-
OFF]
(High) tion 4WD shift switch: 4LO OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (“Wait” function is ON
Output condition to actu- operating.)
SHIFT ACT1 [ON/OFF] ● A/T selector lever “N” posi-
ator motor (High)
tion
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (“Wait” function is ON
SHIFT AC MON1 [ON/ Check signal for transfer operating.)
OFF] control unit signal output ● A/T selector lever “N” posi-
tion
Except the above OFF
● Brake pedal depressed

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 TROUBLE DIAGNOSIS

Monitored item [Unit] Content Condition Display value

● Vehicle stopped 4WD shift switch: 4LO to
● Engine running 4H (“Wait” function is ON
Output condition to actu- operating.)
SHIFT ACT2 [ON/OFF] ● A/T selector lever “N” posi-
ator motor (Low)
tion
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4LO to
● Engine running 4H (“Wait” function is ON
SHIFT AC MON2 [ON/ Check signal for transfer operating.)
OFF] control unit signal output ● A/T selector lever “N” posi-
tion
Except the above OFF
● Brake pedal depressed
T/F F SPEED [km/h] or
Displayed, but do not use.
[mph]
Condition of vehicle Approximately
A/T R SPEED [km/h] or
speed sensor A/T (Revo- During driving matches the out-
[mph]
lution sensor) put shaft speed.
AT GEAR POSI [1/2/3/4/ Condition of A/T selec-
Displays actual A/T gear position. 1/2/3/4/5
5] tor lever position

Specifications Between Transfer Control Unit Terminals

TRANSFER CONTROL UNIT TERMINAL CONNECTOR LAYOUT

WDIA0204E

NOTE:
Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
● Vehicle stopped 4WD shift switch: 2WD 0V
● Engine running

1 GR 2-4WD shift solenoid valve ● A/T selector lever

“N” position 4WD shift switch: AUTO, 4H or 4LO Battery voltage
● Brake pedal
depressed

4WD shift indicator lamp 2WD indicator lamp: OFF Battery voltage
2 B/W
(2WD indicator lamp) 2WD indicator lamp: ON 0V
3 B Ground Always 0V
● Vehicle stopped 4WD shift switch: 4H to 4LO (“Wait” func-
Battery voltage
● Engine running tion is operating.)

4 Y/L Transfer shift high relay ● A/T selector lever

“N” position
Except the above 0V
● Brake pedal
depressed
4WD warning lamp: ON 0V
5 W/B 4WD warning lamp
4WD warning lamp: OFF Battery voltage

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 TROUBLE DIAGNOSIS

Wire
Terminal Item Condition Data (Approx.)
color A
6 B Ground Always 0V
7 L CAN-H — —
B
8 P CAN-L — —

4WD shift switch 4WD shift switch: 2WD Battery voltage

9 G/W Ignition switch: ON
(2WD) 4WD shift switch: AUTO, 4H or 4LO 0V C
● Vehicle stopped 4WD shift switch: AUTO 4 - 14V
● Engine running
● A/T selector lever TF
10 L/W Transfer dropping resistor
“N” position 4WD shift switch: 2WD, 4H or 4LO Less than 1V
● Brake pedal
depressed E
4WD shift indicator lamp Lock indicator lamp of 4WD shift indicator lamp: OFF Battery voltage
11 L
(Lock indicator lamp) Lock indicator lamp of 4WD shift indicator lamp: ON 0V
4LO indicator lamp: OFF Battery voltage F
12 W/G 4LO indicator lamp
4LO indicator lamp: ON 0V
● Vehicle stopped 4WD shift switch: 4LO to 4H (“Wait” func-
Battery voltage G
● Engine running tion is operating.)

13 G/B Transfer shift low relay ● A/T selector lever

“N” position
Except the above 0V H
● Brake pedal
depressed
4WD shift switch: 2WD Battery voltage
I
Battery voltage
(0V for approx.
4WD shift switch: AUTO or 4LO (A/T
2 sec. after
selector lever “P” or “N” position)
● Accelerator pedal shifting to “P” J
depressed and “N”.)
● Vehicle stopped 4WD shift switch: AUTO or 4LO (Except
14 LG Transfer motor relay 0V
● Engine running for A/T selector lever “P” or “N” position)
K
● Brake pedal Battery voltage
depressed 4WD shift switch: 4H (A/T selector lever (0V for approx.
“P” position) 2 sec. after
shifting to “P”.) L
4WD shift switch: 4H (Except for A/T
0V
selector lever “P” position)
ATP indicator lamp: ON 0V
M
15 L/B ATP warning lamp
ATP indicator lamp: OFF Battery voltage
Ignition switch: ON Battery voltage
16 Y/R Power supply
Ignition switch: OFF 0V

4WD shift switch 4WD shift switch: 4H Battery voltage

18 O Ignition switch: ON
(4H) 4WD shift switch: 2WD, AUTO or 4LO 0V
● Vehicle stopped 4WD shift switch: AUTO 1.5 - 3V
● Engine running
Clutch pressure solenoid ● A/T selector lever
19 L
valve “N” position 4WD shift switch: 2WD, 4H or 4LO Less than 1V
● Brake pedal
depressed

4WD shift indicator lamp ● AUTO indicator lamp of 4WD shift indicator lamp: OFF Battery voltage
21 BR
(AUTO indicator lamp) AUTO indicator lamp of 4WD shift indicator lamp: ON 0V

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 TROUBLE DIAGNOSIS

Wire
Terminal Item Condition Data (Approx.)
color
Ignition switch: ON Battery voltage
22 Y/R Power supply
Ignition switch: OFF 0V

4WD shift switch 4WD shift switch: 4LO Battery voltage

23 R Ignition switch: ON
(4LO) 4WD shift switch: 2WD, AUTO or 4H 0V

4WD shift switch 4WD shift switch: AUTO Battery voltage

24 LG/R Ignition switch: ON
(AUTO) 4WD shift switch: 2WD, 4H or 4LO 0V

● Vehicle stopped 4WD shift switch: 2WD, AUTO or 4H Battery voltage

● Engine running 4WD shift switch: 4H to 4LO (While actua- Battery volt-
● A/T selector lever tor motor is operating.) age → 0V
25 V Neutral-4LO switch
“N” position 4WD shift switch: 4LO to 4H (While actua- 0V → Battery
● Brake pedal tor motor is operating.) voltage
depressed 4WD shift switch: 4LO 0V
● Vehicle stopped 4WD shift switch: 4H, AUTO or 2WD 0V
● Engine running
Actuator position switch 2 ● A/T selector lever
27 W/L
(High) “N” position 4WD shift switch: 4LO Battery voltage
● Brake pedal
depressed
28 B/G Sensor ground Always 0V
Ignition switch: ON Battery voltage
29 L/W Ignition switch monitor
Ignition switch: OFF 0V
Ignition switch: ON 0V
30 SB Shut off relay
Ignition switch: OFF Battery voltage
Transfer fluid temperature approx. 20°C
1.1V
Transfer fluid temperature (68°F)
31 G Ignition switch: ON
sensor Transfer fluid temperature approx. 80°C
0.3V
(176°F)
● Vehicle stopped 4WD shift switch: 4H to 4LO (“Wait” func-
Battery voltage
● Engine running tion is operating.)
Transfer shift high relay ● A/T selector lever
33 R/L
monitor “N” position
Except the above 0V
● Brake pedal
depressed
● Vehicle stopped
● Engine running 4WD shift switch: AUTO or 4H (“Wait”
0V
● A/T selector lever function is not operating.)
34 BR Clutch pressure switch “D” position
● Vehicle stopped 4WD shift switch: 2WD (“Wait” function is
Battery voltage
● Engine running not operating.)

● Ignition switch: ON
● A/T selector lever “D” position 0V
● 4WD shift switch: AUTO
● After the vehicle
BR/
35 Line pressure switch has been left at
W ● Ignition switch: ON
room temperature
for 5 minutes and ● A/T selector lever: “P” or "N" position Battery voltage
more with ignition ● 4WD shift switch: other than AUTO
switch in “OFF”
position.

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 TROUBLE DIAGNOSIS

Wire
Terminal Item Condition Data (Approx.)
color A
● Vehicle stopped 4WD shift switch: 4H to 4LO or 4LO to 4H
0V
● Engine running (While actuator motor is operating.)
● A/T selector lever B
40 L ATP switch
“N”
Except the above Battery voltage
● Brake pedal
depressed C
4WD shift switch: 2WD 0V
0V
(Battery volt- TF
4WD shift switch: AUTO or 4LO (A/T age for approx.
selector lever “P” or “N” position) 2 sec. after
● Accelerator pedal shifting to “P”
depressed and “N”.) E
Transfer motor relay moni- ● Vehicle stopped 4WD shift switch: AUTO or 4LO (Except
41 R Battery voltage
tor ● Engine running for A/T selector lever “P” or “N” position)
● Brake pedal 0V F
depressed (Battery volt-
4WD shift switch: 4H (A/T selector lever
age for approx.
“P” position)
2 sec. after
G
shifting to “P”.)
4WD shift switch: 4H (Except for A/T
Battery voltage
selector lever “P” position)
H
● Vehicle stopped 4WD shift switch: 4LO to 4H (“Wait” func-
Battery voltage
● Engine running tion is operating.)
Transfer shift low relay ● A/T selector lever
42 P/G I
monitor “N” position
Except the above 0V
● Brake pedal
depressed
J
● Vehicle stopped 4WD shift switch: 2WD, AUTO or 4H Battery voltage
● Engine running 4WD shift switch: 4H to 4LO (While actua- Battery volt-
● A/T selector lever tor motor is operating.) age → 0V
43 G/Y Wait detection switch K
“N” position 4WD shift switch: 4LO to 4H (While actua- 0V → Battery
● Brake pedal tor motor is operating.) voltage
depressed 4WD shift switch: 4LO 0V
L
● Vehicle stopped 4WD shift switch: 4LO 0V
● Engine running
Actuator position switch 1 ● A/T selector lever
44 LG/B M
(Low) “N” position 4WD shift switch: 2WD, AUTO or 4H Battery voltage
● Brake pedal
depressed
45 B Ground Always 0V

Power supply Ignition switch: ON Battery voltage

47 W
(Memory back-up) Ignition switch: OFF Battery voltage
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS

CONSULT-II Function (ALL MODE AWD/4WD) EDS002HK

FUNCTION
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
ALL MODE AWD/4WD diag-
Description
nostic mode
SELF-DIAG RESULTS Displays transfer control unit self-diagnosis results.
DATA MONITOR Displays transfer control unit input/output data in real time.
Supports inspections and adjustments. Commands are transmitted to the transfer control unit for set-
WORK SUPPORT ting the status suitable for required operation, input/output signals are received from the transfer con-
trol unit and received data is displayed.
CAN DIAG SUPPORT
The results of transmit/receive diagnosis of CAN communication can be read.
MNTR
ECU PART NUMBER Transfer control unit part number can be read.

CONSULT-II SETTING PROCEDURE

CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carry out CAN communication.
NOTE:
For details, refer to the separate “CONSULT-II Operations Manual”.
1. Turn ignition switch “OFF”.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data
link connector on vehicle.
3. Turn ignition switch “ON”.

BBIA0369E

4. Touch “START (NISSAN BASED VHCL)”.

BCIA0029E

5. Touch “ALL MODE AWD/4WD”.

If “ALL MODE AWD/4WD” is not indicated, go to GI-39, "CON-
SULT-II Data Link Connector (DLC) Circuit" .
6. Perform each diagnostic test mode according to each service
procedure.

BCIA0030E

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 TROUBLE DIAGNOSIS

SELF-DIAG RESULT MODE

Operation Procedure A
1. Perform “CONSULT-II SETTING PROCEDURE”. Refer to TF-44, "CONSULT-II SETTING PROCEDURE"
.
2. With engine at idle, touch “SELF-DIAG RESULTS”. B
Display shows malfunction experienced since the last erasing
operation.
NOTE: C
● The details for “TIME” are as follow:

– “0”: Error currently detected with transfer control unit.

– Except for “0”: Error detected in the past and memorized TF

with transfer control unit.
Detects frequency of driving after DTC occurs (frequency
of turning ignition switch “ON/OFF”). E
SDIA2687E

Display Item List

Items (CONSULT-II screen F
Diagnostic item is detected when... Check item
terms)
CONTROL UNIT 1 ● Malfunction is detected in the memory (RAM) system of transfer
TF-57, "Transfer Control Unit"
[P1802] control unit.
G
CONTROL UNIT 2 ● Malfunction is detected in the memory (ROM) system of transfer
TF-57, "Transfer Control Unit"
[P1803] control unit.
CONTROL UNIT 3 ● Malfunction is detected in the memory (EEPROM) system of H
TF-57, "Transfer Control Unit"
[P1804] transfer control unit.
● Malfunction is detected in output shaft revolution signal that is
VHCL SPEED SEN·AT output from TCM through CAN communication. TF-58, "Output Shaft Revolution
[P1807] Signal (TCM)" I
● Improper signal is input while driving.
● Malfunction is detected in vehicle speed signal that is output from
VHCL SPEED SEN·ABS ABS actuator and electric unit (control unit) through CAN commu- TF-58, "Vehicle Speed Sensor
nication. J
[P1808] (ABS)"
● Improper signal is input while driving.
CONTROL UNIT 4
● AD converter system of transfer control unit is malfunctioning. TF-57, "Transfer Control Unit" K
[P1809]
4L POSI SW TF ● Improper signal from neutral-4LO switch is input due to open or
TF-59, "Neutral-4LO Switch"
[P1810] short circuit.
L
BATTERY VOLTAGE ● Power supply voltage for transfer control unit is abnormally low TF-54, "Power Supply Circuit For
[P1811] while driving. Transfer Control Unit"
4WD MODE SW ● More than two switch inputs are simultaneously detected due to
TF-62, "4WD Shift Switch" M
[P1813] short circuit of 4WD shift switch.
4WD DETECT SWITCH ● Improper signal from wait detection switch is input due to open or
TF-66, "Wait Detection Switch"
[P1814] short circuit.
PNP SW/CIRC ● When A/T PNP switch signal is malfunction or communication TF-69, "PNP Switch Signal
[P1816] error between the vehicles. (TCM)"
● Motor does not operate properly due to open or short circuit in
actuator motor.
SHIFT ACTUATOR ● Malfunction is detected in the actuator motor. (When 4WD shift
TF-70, "Actuator Motor"
[P1817] switch is operated and actuator motor is not operated)
● Malfunction is detected in transfer shift high relay and transfer
shift low relay.
● Improper signal from actuator position switch is input due to open
SHIFT ACT POSI SW or short circuit. TF-77, "Actuator Position
[P1818] Switch"
● Malfunction is detected in the actuator position switch.

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 TROUBLE DIAGNOSIS

Items (CONSULT-II screen

Diagnostic item is detected when... Check item
terms)
● Transfer control device actuator circuit is shorted or open. (Mal-
functions are detected when transfer shift relay circuit is open/
shorted or relay monitor circuit is open/shorted.) TF-81, "Transfer Control Device"
SHIFT ACT CIR ● Malfunction occurs in transfer control device drive circuit.
[P1819]
● Malfunction is detected in transfer shut off relay.
TF-54, "Power Supply Circuit For
Malfunction is detected in transfer shut off relay.
Transfer Control Unit"
● Malfunction is detected in engine speed signal that is output from
ENGINE SPEED SIG ECM through CAN communication. TF-85, "Engine Speed Signal
[P1820] (ECM)"
● Improper signal is input while driving.
DUTY SOLENOID ● Proper voltage is not applied to clutch pressure solenoid valve TF-86, "Clutch Pressure Sole-
[P1822] due to open or short circuit. noid"
2-4WD SOLENOID ● Proper voltage is not applied to 2-4WD solenoid valve due to
TF-91, "2-4WD Solenoid"
[P1823] open or short circuit.
MOTOR RELAY ● Motor does not operate properly due to open or short circuit in
TF-95, "Transfer Motor"
[P1824] transfer motor or motor relay.
OIL TEMP SEN ● Signal voltage from fluid temperature sensor is abnormally high TF-102, "Transfer Fluid Temper-
[P1826] (Transfer fluid temperature is abnormally low) while driving. ature"
● Improper signal from clutch pressure switch is input due to open
CLUTCH PRES SW or short circuit. TF-105, "Clutch Pressure
[P1827] Switch"
● Malfunction occurs in clutch pressure switch or hydraulic circuit.
● Improper signal from line pressure switch is input due to open or
LINE PRES SW short circuit. TF-108, "Line Pressure Switch"
[P1828]
● Malfunction occurs in line pressure switch or hydraulic circuit.
● Malfunction is detected in accelerator pedal position signal that is
THROTTLE POSI SEN output from ECM through CAN communication. TF-111, "Throttle Position Signal
[P1829] ● Signal voltage from accelerator pedal position sensor is abnor- (ECM)"
mally high or low.
● Malfunction is detected in ABS operation signal that is output
ABS OP SIG TF-111, "ABS Operation Signal
from ABS actuator and electric unit (control unit) through CAN
[P1830] (ABS)"
communication.
● Malfunction is detected in VDC operation signal that is output
VDC OP SIG TF-112, "VDC Operation Signal
from ABS actuator and electric unit (control unit) through CAN
[P1831] (ABS)"
communication.
TCS OP SIG ● Malfunction is detected in TCS operation signal that is output TF-112, "TCS Operation Signal
[P1832] from ABS through CAN communication. (ABS)"
CAN COMM CIRCUIT TF-113, "CAN Communication
● Malfunction has been detected from CAN communication line.
[U1000] Line"
NO DTC IS DETECTED.
FURTHER TESTING MAY ● No NG item has been detected. —
BE REQUIRED.
CAUTION:
● If “CAN COMM CIRCUIT [U1000]” is displayed with other DTCs, first perform the trouble diagnosis for CAN communica-
tion line.
● If “VHCL SPEED SEN·AT [P1808]”, “ABS OP SIG [P1830]”, “VDC OP SIG [P1831]” or “TCS OP SIG [P1832]” is displayed,
first perform the trouble diagnosis for ABS system.
● If “VHCL SPEED SEN·AT [P1808]”, is displayed, first perform the trouble diagnosis for A/T system.
NOTE:
● If "SHIFT ACT POSI SW [P1818]" or “SHIFT ACT CIR [P1819]” is displayed, first erase self-diagnostic results. ("SHIFT ACT POSI
SW [P1818]" or “SHIFT ACT CIR [P1819]” may be displayed after installing transfer control unit or transfer assembly.)
● If “CL PRES SW [P1827]” or “LINE PRES SW [P1828]” is displayed only while driving in reverse, check the continuity of “R” posi-
tion on A/T PNP switch. When there is nothing wrong with the electrical system, check the hydraulic system.

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 TROUBLE DIAGNOSIS

How to Erase Self-diagnostic Results

1. Perform applicable inspection of malfunctioning item and then repair or replace. A
2. Start engine and select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE” on CONSULT-II screen to erase DTC memory.
B
CAUTION:
If memory cannot be erased, perform applicable diagnosis.
DATA MONITOR MODE C
Operation Procedure
1. Perform “CONSULT-II SETTING PROCEDURE”. Refer to TF-44, "CONSULT-II SETTING PROCEDURE"
. TF
2. Touch “DATA MONITOR”.
3. Select from “SELECT MONITOR ITEM”, screen of data monitor mode is displayed.
NOTE: E
When malfunction is detected, CONSULT-II performs REAL-TIME DIAGNOSIS.
Also, any malfunction detected while in this mode will be displayed at real time.
Display Item List F
×: Standard –: Not applicable
Monitor item selection

Monitored item (Unit) SELEC- Remarks

G
ECU INPUT MAIN
TION FROM
SIGNALS SIGNALS
MENU
Wheel speed calculated by ABS actuator and H
VHCL/S SEN·FR [km/h] or [mph] × – × electric unit (control unit).
Signal input with CAN communication line.
Wheel speed calculated by TCM. I
VHCL/S SEN·RR [km/h] or [mph] × – ×
Signal input with CAN communication line.
Engine speed calculated by ECM.
ENGINE SPEED [rpm] × – ×
Signal input with CAN communication line.
J
Accelerator pedal position (APP) sensor sig-
THRTL POS SEN [V] × – × nal voltage is displayed.
Signal input with CAN communication line.
K
Transfer fluid temperature sensor signal volt-
FLUID TEMP SE [V] × – ×
age is displayed.
BATTERY VOLT [V] × – × Power supply voltage for transfer control unit.
L
2WD SWITCH [ON/OFF] × – × 4WD shift switch status is displayed.
AUTO SWITCH [ON/OFF] × – × 4WD shift switch status is displayed.
4WD shift switch status is displayed. M
LOCK SWITCH [ON/OFF] × – ×
(LOCK means 4H of 4WD shift switch.)
4WD shift switch status is displayed.
4L SW [ON/OFF] × – ×
(4L means 4LO of 4WD shift switch.)
N POSI SW TF [ON/OFF] × – × Neutral-4LO switch signal status is displayed.
ATP SWITCH [ON/OFF] × – × ATP switch signal status is displayed.
WAIT DETCT SW [ON/OFF] × – × Wait detection switch status is displayed.
LINE PRES SW [ON/OFF] × – × Line pressure switch status is displayed.
CL PRES SW [ON / OFF] × – × Clutch pressure switch status is displayed.
“N” position signal of A/T PNP switch status
N POSI SW AT [ON/OFF] × – × is displayed.
Signal input with CAN communication line.
“R” position signal of A/T PNP switch status
R POSI SW AT [ON/OFF] × – × is displayed.
Signal input with CAN communication line.

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 TROUBLE DIAGNOSIS

Monitor item selection

Monitored item (Unit) SELEC- Remarks

ECU INPUT MAIN
TION FROM
SIGNALS SIGNALS
MENU
“P” position signal of A/T PNP switch status is
P POSI SW AT [ON/OFF] × – × displayed.
Signal input with CAN communication line.
ABS operation signal status is displayed.
ABS OPER SW [ON/OFF] × – ×
Signal input with CAN communication line.
VDC operation signal status is displayed.
VDC OPER SW [ON/OFF] × – ×
Signal input with CAN communication line.
TCS operation signal status is displayed.
TCS OPER SW [ON/OFF] × – ×
Signal input with CAN communication line.
Thottle position status is displayed.
THROTTLE POSI [0.0/8] – × ×
Signal input with CAN communication line.
Control status of 4WD recognized by transfer
4WD MODE [AUTO/LOCK/2WD/4L] – × ×
control unit. (AUTO, 4H, 2WD or 4LO)
Vehicle speed recognized by transfer control
VHCL/S COMP [km/h] or [mph] – × ×
unit.
Calculated torque recognized by transfer
COMP CL TORQ [kgm] – × ×
control unit.
DUTY SOLENOID [%] – × × Control value of clutch pressure solenoid.
2-4WD SOL [ON/OFF] – × × Output condition to 2-4WD solenoid.
Check signal for transfer control unit signal
2-4WD SOL MON [ON/OFF] – – ×
output.
Transfer motor relay signal status is dis-
MOTOR RELAY [ON/OFF] – × ×
played.
Check signal for transfer control unit signal
MOTOR RELAY MON [ON/OFF] – – ×
output.
Control status of 4WD warning lamp is dis-
4WD FAIL LAMP [ON/OFF] – × ×
played.
Control status of 4WD shift indicator lamp
2WD IND [ON/OFF] – – ×
(2WD indicator lamp) is displayed.
Control status of 4WD shift indicator lamp
AUTO IND [ON/OFF] – – ×
(2WD and AUTO indicator lamp) is displayed.
Control status of 4WD shift indicator lamp
LOCK IND [ON/OFF] – – × (2WD, AUTO and Lock indicator) is dis-
played.
Control status of 4LO indicator lamp is dis-
4L IND [ON/OFF] – – ×
played.
Control status of ATP warning lamp is dis-
ATP IND [ON/OFF] – – ×
played.
Actuator position switch 1 (Low) signal status
SHIFT POS SW1 [ON/OFF] × – ×
is displayed.
Actuator position switch 2 (high) signal status
SHIFT POS SW2 [ON/OFF] × – ×
is displayed.
Output condition to actuator motor (clock-
SHIFT ACT1 [ON/OFF] – × ×
wise)
Check signal for transfer control unit signal
SHIFT AC MON1 [ON/OFF] × – ×
output
Output condition to actuator motor (counter-
SHIFT ACT2 [ON/OFF] – × ×
clockwise)
Check signal for transfer control unit signal
SHIFT AC MON2 [ON/OFF] × – ×
output

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 TROUBLE DIAGNOSIS

Monitor item selection

A
Monitored item (Unit) SELEC- Remarks
ECU INPUT MAIN
TION FROM
SIGNALS SIGNALS
MENU
T/F F SPEED [km/h] or [mph] × – × Displayed, but do not use. B
Output shaft revolution signal (Revolution
A/T R SPEED [km/h] or [mph] × – × sensor) calculated by TCM.
Signal input with CAN communication line. C
AT GEAR POSI [1/2/3/4/5] × – × A/T actual gear position is displayed.
The value measured by the voltage probe is
Voltage [V] – – ×
displayed. TF
Frequency [Hz] – – ×
DUTY-HI (high) [%] – – ×
The value measured by the pulse probe is E
DUTY-LOW (low) [%] – – ×
displayed.
PLS WIDTH-HI [msec] – – ×
PLS WIDTH-LOW [msec] – – × F
WORK SUPPORT
When there is no problem with transfer and 4WD system, following symptom in “AUTO” mode may be claimed
by a customer. G
● Vibration when accelerating on a low µ road (snow-covered or icy road)
It is possible to deal with these symptoms by changing “CLUTCH FORCE RELEASE LIMIT VALUE”.
However, be careful when changing the values because it may adversely affect driving performance. H
NOTE:
A slight shock is felt at a few hertz as if it were being pushed lightly from behind.
I
Operation Procedure
1. Perform “CONSULT-II SETTING PROCEDURE”. Refer to TF-44, "CONSULT-II SETTING PROCEDURE"
.
J
2. Touch “WORK SUPPORT”.
3. Select from “CLUTCH/F RLS LIM ADJ”, screen of data monitor mode is displayed.
K

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 TROUBLE DIAGNOSIS

Clutch Force Release Limit Adjustment

1. Current CLUTCH FORCE RELEASE LIMIT value “0.3 kgm”
appears under “CONDITION SETTING” on CONSULT-II display.
1.2 kg-m : Tight corner braking symptom is allevi-
ated. However, vibration may occur when
accelerating on a low µ road (icy road, etc.).
0.3 kg-m : Initial set value.
0.2 kg-m : Do not set to this value because the tight
corner braking symptom will get worse.
2. Touch “1.2” on the display. SMT968D

3. Display changes to “NOW ADJUSTING” in a short time.

SMT969D

4. When clutch force release limit value is set to “1.2 kgm”, current
value “0.3 kgm” shown on display will be replaced by “1.2 kgm”
and “ADJUSTMENT COMPLETE” will appear at the same time.
Clutch force release limit value setting is now complete.

SMT970D

Self-diagnostic Procedure EDS002HL

SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)

Refer to TF-45, "SELF-DIAG RESULT MODE" .
SELF-DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-II)
Description
If the engine starts when there is something wrong with the 4WD system, the 4WD warning lamp turns ON or
flickers in the combination meter. When the system functions properly, the warning lamp turns ON when the
ignition switch is turned to “ON”, and it turns OFF after engine starts. To locate the cause of a problem, start
the self-diagnosis function. The 4WD warning lamp in the combination meter will indicate the problem area by
flickering according to the self-diagnostic results. As for the details of the 4WD warning lamp flickering pat-
terns, refer to TF-51, "Diagnostic Procedure" .

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 TROUBLE DIAGNOSIS

Diagnostic Procedure
1. Warn up engine. A
2. Move A/T selector lever to “P” position.
3. Turn 4WD shift switch to “2WD” position.
B
4. Turn ignition switch “ON” and “OFF” at least twice, and then turn ignition switch “OFF”.
5. Turn 4WD shift switch to “AUTO” position.
6. Turn ignition switch “ON”. (Do not start engine.)
C
7. 4WD warning lamp ON.
If 4WD warning lamp does not turn ON, refer to TF-121, "4WD Warning Lamp Does Not Turn ON" .
8. Move A/T selector lever to “R” position. TF
9. Turn 4WD shift switch to “2WD”, “AUTO” and “2WD” in order.
10. Move A/T selector lever to “D” position.
11. Turn 4WD shift switch to “LOCK”, “AUTO” and “LOCK” in order. E
12. Move A/T selector lever to “N” position.
13. Turn 4WD shift switch to “AUTO” position.
14. Move A/T selector lever to “P” position. F
15. Read the flickering of 4WD warning lamp.
Refer to TF-51, "Judgement Self-diagnosis" .
G
Judgement Self-diagnosis
When a malfunction is detected, the malfunction route is indicated by flickering of the 4WD warning lamp.
H

PDIA0227E
K

Flickering pattern or
Items Malfunction Check items
flickering condition L
● Malfunction is detected in output shaft revolution signal TF-58, "Output Shaft
Output shaft revolution that is output from TCM through CAN communication.
2 Revolution Signal
signal (from TCM)
● Improper signal is input while driving. (TCM)"
M
Clutch pressure sole- ● Proper voltage is not applied to clutch pressure solenoid TF-86, "Clutch Pres-
3
noid signal valve due to open or short circuit. sure Solenoid"
● Proper voltage is not applied to 2-4WD solenoid valve TF-91, "2-4WD Sole-
4 2-4WD solenoid signal
due to open or short circuit. noid"
● Motor does not operate properly due to open or short cir-
5 Transfer motor TF-95, "Transfer Motor"
cuit in transfer motor or motor relay.
● Malfunction is detected in vehicle speed signal that is
Vehicle speed signal output from ABS actuator and electric unit (control unit) TF-58, "Vehicle Speed
6 through CAN communication.
(from ABS) Sensor (ABS)"
● Improper signal is input while driving.
● Malfunction has been detected from CAN communica- TF-113, "CAN Commu-
7 CAN communication
tion line. nication Line"
TF-54, "Power Supply
● AD converter system of transfer control unit is malfunc-
8 AD converter Circuit For Transfer
tioning.
Control Unit"

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 TROUBLE DIAGNOSIS

Flickering pattern or
Items Malfunction Check items
flickering condition
● Signal voltage from fluid temperature sensor is abnor-
Transfer fluid tempera- TF-102, "Transfer Fluid
9 mally high (Transfer fluid temperature is abnormally low)
ture Temperature"
while driving.
● Improper signal from neutral-4LO switch is input due to TF-59, "Neutral-4LO
10 Neutral-4LO switch
open or short circuit. Switch"
● Improper signal from clutch pressure switch is input due
to open or short circuit. TF-105, "Clutch Pres-
11 Clutch pressure switch
● Malfunction occurs in clutch pressure switch or hydraulic sure Switch"
circuit.
● Improper signal from line pressure switch is input due to
open or short circuit. TF-108, "Line Pressure
12 Line pressure switch
● Malfunction occurs in line pressure switch or hydraulic Switch"
circuit.
● Malfunction is detected in engine speed signal that is
Engine speed signal output from ECM through CAN communication. TF-85, "Engine Speed
13
(from ECM) Signal (ECM)"
● Improper signal is input while driving.
● Malfunction is detected in accelerator pedal position sig-
nal that is output from ECM through CAN communica-
Throttle position sen- tion. TF-111, "Throttle Posi-
14
sor (from ECM) tion Signal (ECM)"
● Signal voltage from accelerator pedal position sensor is
abnormally high or low.
TF-54, "Power Supply
● Power supply voltage for transfer control unit is abnor-
15 Power supply Circuit For Transfer
mally low while driving.
Control Unit"
● More than two switch inputs are simultaneously detected TF-62, "4WD Shift
16 4WD shift switch
due to short circuit of 4WD shift switch. Switch"
● Malfunction is detected in ABS operation signal that is
ABS operation signal TF-111, "ABS Operation
17 output from ABS actuator and electric unit (control unit)
(from ABS) Signal (ABS)"
through CAN communication.
● Improper signal from wait detection switch is input due to TF-66, "Wait Detection
18 Wait detection switch
open or short circuit. Switch"
● Motor does not operate properly due to open or short cir-
cuit in actuator motor.
TF-70, "Actuator
● Malfunction is detected in the actuator motor. (When
Motor", TF-54, "Power
19 Actuator motor 4WD shift switch is operated and actuator motor is not
Supply Circuit For
operated)
Transfer Control Unit"
● Malfunction is detected in transfer shift high relay and
transfer shift low relay.
● Improper signal from actuator position switch is input
Actuator position due to open or short circuit. TF-77, "Actuator Posi-
20
switch tion Switch"
● Malfunction is detected in the actuator position switch.
● Transfer control device actuator circuit is shorted or
open. (Malfunctions are detected when motor relay cir-
cuit is open/shorted or relay transfer shift circuit is open/ TF-81, "Transfer Con-
shorted.) trol Device"
21 Actuator circuit
● Malfunction occurs in transfer control device drive circuit.
TF-54, "Power Supply
● Malfunction is detected in transfer shut off relay. Circuit For Transfer
Control Unit"
● Malfunction is detected in VDC operation signal that is
VDC operation signal TF-112, "VDC Opera-
22 output from ABS actuator and electric unit (control unit)
(from VDC) tion Signal (ABS)"
through CAN communication.
● Malfunction is detected in TCS operation signal that is
TCS operation signal TF-112, "TCS Opera-
23 output from ABS actuator and electric unit (control unit)
(from TCS) tion Signal (ABS)"
through CAN communication.

Revision: October 2005 TF-52 2005 QX56

 TROUBLE DIAGNOSIS

Flickering pattern or
Items Malfunction Check items
flickering condition A
PNP switch signal ● When A/T PNP switch signal is malfunctioning or com- TF-69, "PNP Switch
24
(from TCM) munication error between the vehicles. Signal (TCM)"
Repeats flickering B
— Circuits that the self-diagnosis covers have no malfunction. —
every 2 to 5 sec.

● Power supply failure of memory back-up. TF-54, "Power Supply

Repeats flickering
every 0.25 sec.
Data erase display Circuit For Transfer C
● Battery performance is poor. Control Unit"
TF-69, "PNP Switch
PNP switch or 4WD ● PNP switch or 4WD shift switch circuit is shorted or
No flickering Signal (TCM)", TF-62, TF
shift switch open.
"4WD Shift Switch"
CAUTION:
● If “CAN communication” is displayed with other DTCs, first perform the trouble diagnosis for CAN communication line.
E
● If “ABS operation signal”, “VDC operation signal" or “TCS operation signal" is displayed, first perform the trouble diag-
nosis for ABS system.
● If “Output shaft revolution signal” is displayed, first perform the trouble diagnosis for A/T system.
F
NOTE:
● If "actuator position switch" or “actuator circuit” is displayed, first erase self-diagnostic results. ("Actuator position switch" or “actua-
tor circuit” may be displayed after installing transfer control unit or transfer assembly.)
● If “clutch pressure switch” or “line pressure switch” is displayed only while driving in reverse, check the continuity of “R” position on G
A/T PNP switch. When there is nothing wrong with the electrical system, check the hydraulic system.

ERASE SELF-DIAGNOSIS
H
● In order to make it easier to find the cause of hard-to-duplicate malfunctions, malfunction information is
stored into the control unit as necessary during use by the user. This memory is not erased no matter how
many times the ignition switch is turned ON and OFF.
I
● However, this information is erased by turning ignition switch “OFF” after performing self-diagnostics or by
erasing the memory using the CONSULT-II.

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 TROUBLE DIAGNOSIS FOR SYSTEM

TROUBLE DIAGNOSIS FOR SYSTEM PFP:00000

Power Supply Circuit For Transfer Control Unit EDS002I4

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Monitored item [Unit] Content Condition Display value
Power supply voltage for
BATTERY VOLT [V] Ignition switch: ON Battery voltage
transfer control unit

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
3 B Ground Always 0V
6 B Ground Always 0V
Ignition switch: ON Battery voltage
16 Y/R Power supply
Ignition switch: OFF 0V
Ignition switch: ON Battery voltage
22 Y/R Power supply
Ignition switch: OFF 0V
Ignition switch: ON Battery voltage
29 L/W Ignition switch monitor
Ignition switch: OFF 0V
Ignition switch: ON 0V
30 SB Shut off relay
Ignition switch: OFF Battery voltage
45 B Ground Always 0V

Power supply Ignition switch: ON Battery voltage

47 W
(Memory back-up) Ignition switch: OFF Battery voltage
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK POWER SUPPLY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Connect transfer control unit harness connector. B
3. Check voltage between transfer control unit harness connector
terminals and ground.
C
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142
22 (Y/R) - Ground 0V TF
29 (L/W) - Ground
E143 30 (SB) - Ground
Battery voltage E
47 (W) - Ground
WDIA0165E

4. Turn ignition switch “ON”. (Do not start engine.) F

5. Check voltage between transfer control unit harness connector
terminals and ground.
G
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142
22 (Y/R) - Ground Battery voltage H
29 (L/W) - Ground
E143 30 (SB) - Ground 0V
I
WDIA0166E
47 (W) - Ground Battery voltage

OK or NG
OK >> GO TO 2. J
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
● 10A fuses No. 26 located in fuse and fusible link box and No. 59 located in the fuse and relay
box. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" . K
● 20A fuse No. 53 located in the IPDM E/R. Refer to PG-4, "POWER SUPPLY ROUTING CIR-
CUIT" .
● Harness for short or open between battery and transfer control unit harness connector termi- L
nals 47.
● Harness for short or open between battery and transfer control unit harness connector terminal
29. M
● Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 1 (G), and 3 (G).
● Harness for short or open between transfer shut off relay harness connector E69 terminal 2
(SB) and transfer control unit harness connector terminal 30.
● Harness for short or open between transfer shut off relay harness connector E69 terminal 5 (Y/
R) and transfer control unit harness connector terminals 16 (Y/R) and 22 (Y/R).
● Battery and ignition switch. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .

● Transfer shut off relay. Refer to TF-57, "COMPONENT INSPECTION" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK GROUND CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminals 3 (B), 6 (B), E143 terminal 45 (B) and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.

SDIA2691E

3. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 4.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

4. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) A
2. Remove transfer shut off relay. Refer to TF-22, "Location of Electrical Parts" .
3. Apply 12V direct current between transfer shut off relay termi-
nals 1 and 2. B
4. Check continuity between relay terminals 3 and 5.
Condition Continuity C
12V direct current supply between terminals 1 and 2 Yes
OFF No
TF
5. If NG, replace the transfer shut off relay. Refer to TF-22, "Loca-
tion of Electrical Parts" .
SCIA1245E
E
Transfer Control Unit EDS002I5

DIAGNOSTIC PROCEDURE
1. INSPECTION START F

Do you have CONSULT-II?

YES or NO G
YES >> GO TO 2.
NO >> GO TO 3.
H
2. PERFORM SELF-DIAGNOSIS (WITH CONSULT-II)
With CONSULT-II
I
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE”. J
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Perform the self-diagnosis again.
Is the “CONTROL UNIT 1 [P1802]”, “CONTROL UNIT 2 [P1803]”, “CONTROL UNIT 3 [P1804]” or “CONTROL K
UNIT 4 [P1809]” displayed?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End. L

3. PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-II)

Without CONSULT-II M
1. Perform the self-diagnosis and then erase self-diagnostic results. Refer to TF-50, "SELF-DIAGNOSTIC
PROCEDURE (WITHOUT CONSULT-II)" and TF-53, "ERASE SELF-DIAGNOSIS" .
2. Perform the self-diagnosis again.
Do the self-diagnostic results indicate AD converter?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.

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 TROUBLE DIAGNOSIS FOR SYSTEM

Output Shaft Revolution Signal (TCM) EDS002I6

DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH TCM
Perform self-diagnosis with TCM. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.

2. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with TCM again. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE
(WITH CONSULT-II)" .
Vehicle Speed Sensor (ABS) EDS002I7

DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-29, "SELF-DIAGNO-
SIS" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.

2. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ABS actuator and electric unit (control unit) again. Refer to BRC-29,
"SELF-DIAGNOSIS" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

Neutral-4LO Switch EDS002I8

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE A

Data are reference value.
Monitored item Content Condition Display value
4WD shift switch: 2WD, B
OFF
AUTO or 4H
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (While actuator OFF → ON C
N POSI SW TF [ON/ Condition of neutral-4LO motor is operating.)
OFF] switch ● A/T selector lever “N”
position 4WD shift switch: 4LO to
● Brake pedal depressed 4H (While actuator motor ON → OFF
is operating.)
TF
4WD shift switch: 4LO ON

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE E

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
F
● Vehicle stopped 4WD shift switch: 2WD, AUTO or 4H Battery voltage
● Engine running 4WD shift switch: 4H to 4LO (While actua- Battery volt-
A/T selector tor motor is operating.) age → 0V
25 V Neutral-4LO switch ● G
lever “N” position 4WD shift switch: 4LO to 4H (While actua- 0V → Battery
● Brake pedal tor motor is operating.) voltage
depressed 4WD shift switch: 4LO 0V H
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.
I

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
1. CHECK 4LO POSITION SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “N POSI SW TF”.
Condition Display value
4WD shift switch: 2WD,
OFF
AUTO or 4H

● Vehicle stopped 4WD shift switch: 4H to

4LO (While actuator OFF → ON
● Engine running motor is operating.)
● A/T selector lever “N” position
4WD shift switch: 4LO to
● Brake pedal depressed 4H (While actuator motor ON → OFF
is operating.) SDIA2692E

4WD shift switch: 4LO ON

Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)
4WD shift switch: Battery
2WD, AUTO or 4H voltage
● Vehicle stopped
4WD shift switch: 4H Battery
● Engine running to 4LO (While actuator voltage
25 (V) - ● A/T selector lever motor is operating.) → 0V
E143
Ground “N” position SDIA2693E

4WD shift switch: 4LO 0V →

● Brake pedal to 4H (While actuator Battery
depressed motor is operating.) voltage
4WD shift switch: 4LO 0V

OK or NG
OK >> GO TO 5.
NG >> GO TO 2.

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND NEUTRAL-4LO SWITCH

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the neutral-4LO switch harness connector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 25 (V) and neutral-4LO switch harness con-
nector F60 terminal 13 (V).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

SDIA2694E

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK GROUND CIRCUIT A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect neutral-4LO switch harness connector.
3. Check continuity between neutral-4LO switch harness connec- B
tor F60 terminal 12 (B) and ground.
Continuity should exist.
C
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4. TF
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
E
SDIA2695E

4. CHECK 4LO SWITCH

F
1. Turn ignition switch “OFF”.
2. Disconnect neutral-4LO switch harness connector.
3. Remove neutral-4LO switch. Refer to TF-22, "Location of Electrical Parts" . G
4. Push and release neutral-4LO switch and check continuity
between neutral-4LO switch terminals 12 and 13.
H
Terminal Condition Continuity
Push neutral-4LO switch Yes
12 - 13
Release neutral-4LO switch No I
OK or NG
OK >> GO TO 5.
NG >> Replace neutral-4LO switch. Refer to TF-22, "Location J
of Electrical Parts" . SDIA2696E

5. CHECK TRANSFER CONTROL UNIT K

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
L
OK or NG
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts. M

6. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect neutral-4LO switch harness connector.
3. Remove neutral-4LO switch. Refer to TF-22, "Location of Electrical Parts" .
4. Push and release neutral-4LO switch and check continuity
between neutral-4LO switch terminals 12 and 13.
Terminal Condition Continuity
Push neutral-4LO switch Yes
12 - 13
Release neutral-4LO switch No

5. If NG, replace the neutral-4LO switch. Refer to TF-22, "Location

of Electrical Parts" .

SDIA2696E

4WD Shift Switch EDS002I9

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Monitored item [Unit] Content Condition Display value

2WD SWITCH [ON/ Input condition from 4WD 4WD shift switch: 2WD ON
OFF] shift switch 4WD shift switch: AUTO, 4H or 4LO OFF

AUTO SWITCH [ON/ Input condition from 4WD 4WD shift switch: AUTO ON
OFF] shift switch 4WD shift switch: 2WD, 4H or 4LO OFF

LOCK SWITCH [ON/ Input condition from 4WD 4WD shift switch: 4H ON
OFF] shift switch 4WD shift switch: 2WD, AUTO or 4LO OFF

Input condition from 4WD 4WD shift switch: 4LO ON

4L SWITCH [ON/OFF]
shift switch 4WD shift switch: 2WD, AUTO or 4H OFF
● Vehicle stopped 4WD shift switch: 2WD 2WD
Control status of 4WD ● Engine running 4WD shift switch: AUTO AUTO
4WD MODE [AUTO/ (Output condition of 4WD
LOCK/2WD/4L] shift indicator lamp and ● A/T selector lever “N” 4WD shift switch: 4H LOCK
4LO indicator lamp) position
● Brake pedal depressed 4WD shift switch: 4LO 4L

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color

4WD shift switch 4WD shift switch: 2WD Battery voltage

9 G/W Ignition switch: ON
(2WD) 4WD shift switch: AUTO, 4H or 4LO 0V

4WD shift switch 4WD shift switch: 4H Battery voltage

18 O Ignition switch: ON
(4H) 4WD shift switch: 2WD, AUTO or 4LO 0V

4WD shift switch 4WD shift switch: 4LO Battery voltage

23 R Ignition switch: ON
(4LO) 4WD shift switch: 2WD, AUTO or 4H 0V

4WD shift switch 4WD shift switch: AUTO Battery voltage

24 LG/R Ignition switch: ON
(AUTO) 4WD shift switch: 2WD, 4H or 4LO 0V
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK 4WD SHIFT SWITCH SIGNAL
With CONSULT-II
B
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out ON/OFF switching action of the “2WD SWITCH”,
C
“AUTO SWITCH”, “LOCK SWITCH”, “4L SWITCH” with operat-
ing 4WD shift switch.

TF

SDIA2697E
F

Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.) G
2. Check voltage between transfer control unit harness connector
terminals and ground.
H
Terminal Voltage
Connector Condition
(Wire color) (Approx.)

9 (G/W) - 4WD shift switch: 2WD Battery voltage

ground
I
4WD shift switch: AUTO, 4H or 4LO 0V
4WD shift switch: 4H Battery voltage
18 (O) -
ground 4WD shift switch: 2WD, AUTO or
0V
J
4LO
E142 WDIA0148E
4WD shift switch: 4LO Battery voltage
23 (R) -
ground 4WD shift switch: 2WD, AUTO or K
0V
4H

24 (LG/R) - 4WD shift switch: AUTO Battery voltage

ground 4WD shift switch: 2WD, 4H or 4LO 0V L

OK or NG
OK >> GO TO 5. M
NG >> GO TO 2.

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK 4WD SHIFT SWITCH POWER SUPPLY CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect 4WD shift switch harness connector.
3. Check voltage between 4WD shift switch harness connector ter-
minal 1 and ground.
Connector Terminal (Wire color) Voltage (Approx.)
M141 1 (W/R) - Ground 0V

SDIA2383E

4. Turn ignition switch “ON”. (Do not start engine.)

5. Check voltage between 4WD shift switch harness connector ter-
minal 1 and ground.
Connector Terminal (Wire color) Voltage (Approx.)
M141 1 (W/R) - Ground Battery voltage
OK or NG
OK >> GO TO 3.
NG >> Go to TF-54, "Power Supply Circuit For Transfer Control
Unit" .
PDIA0210E

3. CHECK HARNESS BETWEEN 4WD SHIFT SWITCH AND TRANSFER CONTROL UNIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the 4WD shift switch harness connector.
3. Check continuity between the following terminals.
– Transfer control unit harness connector E142 terminal 9 (G/W)
and 4WD shift switch harness connector M141 terminal 2 (G/W).
– Transfer control unit harness connector E142 terminal 18 (O)
and 4WD shift switch harness connector M141 terminal 5 (O).
– Transfer control unit harness connector E142 terminal 23 (R)
and 4WD shift switch harness connector M141 terminal 6 (R).
– Transfer control unit harness connector E142 terminal 24 (LG/R)
and 4WD shift switch harness connector M141 terminal 3 (LG/
R). SDIA2699E

Continuity should exist.

Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
● Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 3 (G).
● Power supply circuit for transfer control unit. Refer to PG-4, "POWER SUPPLY ROUTING CIR-
CUIT" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

4. CHECK 4WD SHIFT SWITCH A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect 4WD shift switch harness connector.
3. Operate 4WD shift switch and check continuity between 4WD B
shift switch terminals.
Connector Terminal Condition Continuity
C
4WD shift switch: 2WD Yes
1-2 4WD shift switch: AUTO, 4H and
No
4LO TF
4WD shift switch: AUTO Yes
1-3 4WD shift switch: 2WD, 4H and
No
4LO E
WDIA0205E
4WD shift switch: 2WD No
1-4
M141 4WD shift switch: AUTO, 4H and
Yes
4LO F
4WD shift switch: 4H Yes
1-5 4WD shift switch: 2WD, AUTO,
No G
and 4LO
4WD shift switch: 4LO Yes
1-6 4WD shift switch: 2WD, AUTO
and 4H
No H

OK or NG
OK >> GO TO 5. I
NG >> Replace 4WD shift switch.

5. CHECK TRANSFER CONTROL UNIT

J
Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG K
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts. L
6. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while. M
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 second.)
2. Disconnect 4WD shift switch harness connector.
3. Operate 4WD shift switch and check continuity between 4WD
shift switch terminals.
Connector Terminal Condition Continuity
4WD shift switch: 2WD Yes
1-2 4WD shift switch: AUTO, 4H and
No
4LO
4WD shift switch: AUTO Yes
1-3 4WD shift switch: 2WD, 4H and
No
4LO
WDIA0205E
4WD shift switch: 2WD No
1-4
M141 4WD shift switch: AUTO, 4H and
Yes
4LO
4WD shift switch: 4H Yes
1-5 4WD shift switch: 2WD, AUTO,
No
and 4LO
4WD shift switch: 4LO Yes
1-6 4WD shift switch: 2WD, AUTO
No
and 4H

4. If NG, replace the 4WD shift switch.

Wait Detection Switch EDS002IA

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Monitored item Content Condition Display value
4WD shift switch: 2WD,
OFF
AUTO or 4H
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (While actuator OFF → ON
WAIT DETCT SW [ON/ Condition of wait detection motor is operating.)
OFF] switch ● A/T selector lever “N”
position 4WD shift switch: 4LO to
● Brake pedal depressed 4H (While actuator motor ON → OFF
is operating.)
4WD shift switch: 4LO ON

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color

● Vehicle stopped 4WD shift switch: 2WD, AUTO or 4H Battery voltage

● Engine running 4WD shift switch: 4H to 4LO (While actua- Battery volt-
● A/T selector tor motor is operating.) age → 0V
43 G/Y Wait detection switch
lever “N” position 4WD shift switch: 4LO to 4H (While actua- 0V → Battery
● Brake pedal tor motor is operating.) voltage
depressed 4WD shift switch: 4LO 0V
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK WAIT DETECTION SWITCH SIGNAL
With CONSULT-II
B
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “WAIT DETCT SW”.
C
Condition Display value
4WD shift switch: 2WD, AUTO
OFF TF
or 4H

● Vehicle stopped 4WD shift switch: 4H to 4LO

(While actuator motor is operat- OFF → ON
● Engine running ing.) E
● A/T selector lever “N” position
4WD shift switch: 4LO to 4H
● Brake pedal depressed (While actuator motor is operat- ON → OFF
ing.) PDIA0221E
F
4WD shift switch: 4LO ON

Without CONSULT-II G
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground. H

Terminal
Voltage
Connector (Wire Condition
(Approx.)
color) I
4WD shift switch: Battery
2WD, AUTO or 4H voltage
● Vehicle stopped J
4WD shift switch: 4H Battery
● Engine running to 4LO (While actua- voltage
43 (G/Y) ● A/T selector lever tor motor is operating.) → 0V
E143
- Ground “N” position SDIA2701E

4WD shift switch: 4LO 0V → K

● Brake pedal to 4H (While actuator Battery
depressed motor is operating.) voltage
4WD shift switch: 4LO 0V L
OK or NG
OK >> GO TO 5.
NG >> GO TO 2. M

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND WAIT DETECTION SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the wait detection switch harness connector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 43 (G/Y) and wait detection switch harness
connector F59 terminal 10 (G/Y).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

SDIA2702E

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK GROUND CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect wait detection switch harness connector.
3. Check continuity between wait detection switch harness con-
nector F59 terminal 11 (B) and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.

SDIA2703E

4. CHECK WAIT DETECTION SWITCH

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect wait detection switch harness connector.
3. Remove wait detection switch. Refer to TF-22, "Location of Electrical Parts" .
4. Push and release wait detection switch and check continuity
between wait detection switch terminals 10 and 11.
Terminal Condition Continuity
Push wait detection switch Yes
10 - 11
Release wait detection switch No

OK or NG
OK >> GO TO 5.
NG >> Replace wait detection switch. Refer to TF-22, "Loca-
tion of Electrical Parts" . SDIA2704E

5. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

6. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) A
2. Disconnect wait detection switch harness connector.
3. Remove wait detection switch. Refer to TF-22, "Location of Electrical Parts" .
B
4. Push and release wait detection switch and check continuity
between wait detection switch terminals 10 and 11.
Terminal Condition Continuity C
Push wait detection switch Yes
10 - 11
Release wait detection switch No
TF
5. If NG, replace the wait detection switch. Refer to TF-22, "Loca-
tion of Electrical Parts" .

E
SDIA2704E

PNP Switch Signal (TCM) EDS002IB

DIAGNOSTIC PROCEDURE F
1. CHECK DTC WITH TCM
Perform self-diagnosis with TCM. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)" . G
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2. H

2. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref- I
erence Values" .
OK or NG
J
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
K
3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
L
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with TCM again. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE
M
(WITH CONSULT-II)" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

Actuator Motor EDS002IC

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Monitored item Content Condition Display value
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (“Wait” function is ON
Output condition to operating.)
SHIFT ACT1 [ON/OFF] ● A/T selector lever “N”
actuator motor (High)
position
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4H to
● Engine running 4LO (“Wait” function is ON
Check signal for trans-
operating.)
SHIFT AC MON1 [ON/OFF] fer control unit signal ● A/T selector lever “N”
output position
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4LO to
● Engine running 4H (“Wait” function is ON
Output condition to operating.)
SHIFT ACT2 [ON/OFF] ● A/T selector lever “N”
actuator motor (Low)
position
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4LO to
● Engine running 4H (“Wait” function is ON
Check signal for trans-
operating.)
SHIFT AC MON2 [ON/OFF] fer control unit signal ● A/T selector lever “N”
output position
Except the above OFF
● Brake pedal depressed

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
● Vehicle stopped 4WD shift switch: 4H to 4LO (“Wait” func-
Battery voltage
● Engine running tion is operating.)

4 Y/L Transfer shift high relay ● A/T selector

lever “N” position
Except the above 0V
● Brake pedal
depressed
● Vehicle stopped 4WD shift switch: 4LO to 4H (“Wait” func-
Battery voltage
● Engine running tion is operating.)

13 G/B Transfer shift low relay ● A/T selector

lever “N” position
Except the above 0V
● Brake pedal
depressed
● Vehicle stopped 4WD shift switch: 4H to 4LO (“Wait” func-
Battery voltage
● Engine running tion is operating.)
Transfer shift high relay moni- ● A/T selector
33 R/L
tor lever “N” position
Except the above 0V
● Brake pedal
depressed
● Vehicle stopped 4WD shift switch: 4LO to 4H (“Wait” func-
Battery voltage
● Engine running tion is operating.)
Transfer shift low relay moni- ● A/T selector
42 P/G
tor lever “N” position
Except the above 0V
● Brake pedal
depressed
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK ACTUATOR MOTOR SIGNAL
With CONSULT-II
B
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “SHIFT ACT1”, “SHIFT AC MON1”,
C
“SHIFT ACT2” and “SHIFT AC MON2”.
Monitored Display
Condition
item value TF
● Vehicle stopped 4WD shift switch: 4H
● Engine running to 4LO (“Wait” func- ON
tion is operating.)
SHIFT ACT1 ● A/T selector lever “N” posi- E
tion
Except the above OFF
● Brake pedal depressed
PDIA0223E
● Vehicle stopped 4WD shift switch: 4H F
● Engine running to 4LO (“Wait” func- ON
SHIFT AC tion is operating.)
MON1 ● A/T selector lever “N” posi-
tion G
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch:
● Engine running 4LO to 4H (“Wait” H
ON
function is operat-
SHIFT ACT2 ● A/T selector lever “N” posi-
ing.)
tion
● Brake pedal depressed Except the above OFF
I
● Vehicle stopped 4WD shift switch:
● Engine running 4LO to 4H (“Wait”
ON
SHIFT AC function is operat-
MON2 ● A/T selector lever “N” posi- J
ing.)
tion
● Brake pedal depressed Except the above OFF

Without CONSULT-II K
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground. L

Terminal
Voltage
Connector (Wire Condition
(Approx.) M
color)
● Vehicle stopped 4WD shift switch: 4H
Battery
● Engine running to 4LO (“Wait” function
voltage
is operating.)
4 (Y/L) - ● A/T selector lever
Ground “N” position
● Brake pedal Except the above 0V SDIA2705E
depressed
E142
● Vehicle stopped 4WD shift switch: 4LO
Battery
● Engine running to 4H (“Wait” function
voltage
is operating.)
13 (G/B) ● A/T selector lever
- Ground “N” position
● Brake pedal Except the above 0V
depressed

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 TROUBLE DIAGNOSIS FOR SYSTEM

Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)
● Vehicle stopped 4WD shift switch: 4H
Battery
● Engine running to 4LO (“Wait” function
voltage
is operating.)
33 (R/L) - ● A/T selector lever
Ground “N” position
● Brake pedal Except the above 0V
depressed
E143
● Vehicle stopped 4WD shift switch: 4LO
Battery
● Engine running to 4H (“Wait” function
voltage
is operating.)
42 (P/G) ● A/T selector lever
- Ground “N” position
● Brake pedal Except the above 0V
depressed
OK or NG
OK >> GO TO 7.
NG >> GO TO 2.

2. CHECK ACTUATOR MOTOR POWER SUPPLY CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay.
3. Check voltage between transfer shift high relay harness connec-
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
Connector Terminal (Wire color) Voltage (Approx.)
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground

SDIA2707E

4. Turn ignition switch “ON”. (Do not start engine.)

5. Check voltage between transfer shift high relay harness connec-
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
Connector Terminal (Wire color) Voltage (Approx.)
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground

OK or NG
OK >> GO TO 3. SDIA2706E

NG >> Check the following. If any items are damaged, repair or

replace damaged parts.
● 20A fuse [No. 57, located in the fuse block (J/B)]. Refer to PG-4, "POWER SUPPLY ROUTING
CIRCUIT" .
● Harness for short or open between battery, transfer shift high relay harness connector terminal
5 and transfer shift low relay harness connector terminal 5.

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK ACTUATOR MOTOR GROUND CIRCUIT A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "Location of Electrical Parts" .
3. Check continuity between transfer shift high relay harness con- B
nector E46 terminals 1 (B/W), 4 (B), transfer shift low relay har-
ness connector E47 terminal 1 (B/W), 4 (B) and ground.
Continuity should exist. C

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

OK or NG TF
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
E
SDIA2708E

4. CHECK TRANSFER SHIFT RELAY

F
1. Turn ignition switch “OFF”.
2. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "Location of Electrical Parts" .
3. Apply 12V direct current between transfer shift relay terminals 1 G
and 2.
4. Check continuity between relay terminals 3 and 4, 3 and 5.
H
Terminal Condition Continuity
12V direct current supply between terminals 1 and 2 No
3-4
OFF Yes I
12V direct current supply between terminals 1 and 2 Yes
3-5
OFF No
OK or NG LDIA0099E J
OK >> GO TO 5.
NG >> Replace the transfer shut off relay.
K

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 TROUBLE DIAGNOSIS FOR SYSTEM

5. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER SHIFT RELAY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the transfer control device (actuator motor) har-
ness connector.
3. Remove transfer shift high relay and transfer shift low relay.
4. Check continuity between the following terminals.
– Transfer control unit harness connector E143 terminal 33 (R/L)
and transfer control device (actuator motor) harness connector
F58 terminal 21 (R/L).
– Transfer control unit harness connector E143 terminal 42 (P/G)
and transfer control device (actuator motor) harness connector
F58 terminal 24 (P/G).

SDIA2710E

– Transfer control unit harness connector E142 terminal 4 (Y/L)

and transfer shift high relay harness connector E46 terminal 2
(Y/L).
– Transfer control unit harness connector E142 terminal 13 (G/B)
and transfer shift low relay harness connector E47 terminal 2 (G/
B).

SDIA2711E

– Transfer control unit harness connector E143 terminal 33 (R/L)

and transfer shift high relay harness connector E46 terminal 3
(R/L).
– Transfer control unit harness connector E143 terminal 42 (P/G)
and transfer shift low relay harness connector E47 terminal 3 (P/
G).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6. SDIA2712E

NG >> Repair or replace damaged parts.

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 TROUBLE DIAGNOSIS FOR SYSTEM

6. CHECK ACTUATOR MOTOR A

1. Remove transfer control device. Refer to TF-138, "Removal and Installation" .
2. Check operation by applying battery voltage to transfer control
device (actuator motor) terminals 21 and 24. B
CAUTION:
● Do not operate actuator motor for more than 1 second.

● Change the actuator motor position to “HIGH” when C

installing.
● Be careful not to overheat the harness.
TF
Terminal Actuator motor
21 (Battery voltage) - 24 (Ground) Clockwise rotate WDIA0224E

24 (Battery voltage) - 21 (Ground) Counterclockwise rotate E

3. Check continuity between transfer control device (actuator
motor) terminals 21 and 24.
F
21 - 24 : Approx. 0.2 Ω
OK or NG
OK >> GO TO 7. G
NG >> Replace transfer control device (actuator motor). Refer
to TF-138, "Removal and Installation" .
H

SDIA2726E

7. CHECK TRANSFER CONTROL UNIT I

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" . J
OK or NG
OK >> GO TO 8.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. K
If any items are damaged, repair or replace damaged parts.

8. CHECK DTC L
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End. M
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

COMPONENT INSPECTION
Transfer Shift Relay
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "Location of Electrical Parts" .
3. Apply 12V direct current between transfer shift relay terminals 1
and 2.
4. Check continuity between relay terminals 3 and 4, 3 and 5.
Terminal Condition Continuity
12V direct current supply between terminals 1 and 2 No
3-4
OFF Yes
12V direct current supply between terminals 1 and 2 Yes
3-5
OFF No
LDIA0099E
5. If NG, replace transfer shift relay.
Transfer Control Device
1. Remove transfer control device. Refer to TF-138, "Removal and Installation" .
2. Check operation by applying battery voltage to transfer control
device (actuator motor) terminals 21 and 24.
CAUTION:
● Do not operate actuator motor for more than 1 second.

● Change the actuator motor position to “HIGH” when

installing.
● Be careful not to overheat the harness.

Terminal Actuator motor

21 (Battery voltage) - 24 (Ground) Clockwise rotate WDIA0224E

24 (Battery voltage) - 21 (Ground) Counterclockwise rotate

3. Check continuity between transfer control device (actuator

motor) terminals 21 and 24.
21 - 24 : Approx. 0.2 Ω
4. If NG, replace transfer control device (actuator motor). Refer to
TF-138, "Removal and Installation" .

SDIA2726E

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 TROUBLE DIAGNOSIS FOR SYSTEM

Actuator Position Switch EDS002ID

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE A

Data are reference value.
Monitored item [Unit] Content Condition Display value
● Vehicle stopped 4WD shift switch: 4LO ON B
Condition of actuator posi- ● Engine running
SHIFT POS SW1 [ON/
tion switch 1 ● A/T selector lever “N” 4WD shift switch: 2WD,
OFF] OFF
(Low) position AUTO or 4H C
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4H,
ON
● Engine running AUTO or 2WD TF
Condition of actuator posi-
SHIFT POS SW2 [ON/
tion switch 2 ● A/T selector lever “N”
OFF]
(High) position 4WD shift switch: 4LO OFF
● Brake pedal depressed E
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
Wire F
Terminal Item Condition Data (Approx.)
color
● Vehicle stopped 4WD shift switch: 4H, AUTO or 2WD 0V
● Engine running G
Actuator position switch 2 ● A/T selector
27 W/L
(High) lever “N” position 4WD shift switch: 4LO Battery voltage
● Brake pedal H
depressed
● Vehicle stopped 4WD shift switch: 4LO 0V
● Engine running I
Actuator position switch 1 ● A/T selector
44 LG/B
(Low) lever “N” position 4WD shift switch: 2WD, AUTO or 4H Battery voltage
● Brake pedal J
depressed
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.
K

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
1. CHECK ACTUATOR POSITION SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “SHIFT POS SW1” and “SHIFT POS
SW2”.
Monitored item Condition Display value
● Vehicle stopped 4WD shift switch: 4LO ON
● Engine running

SHIFT POS SW1 ● A/T selector lever

4WD shift switch:
“N” position OFF
2WD, AUTO or 4H
● Brake pedal
depressed
SDIA2714E
● Vehicle stopped 4WD shift switch: 4H,
ON
● Engine running AUTO or 2WD

SHIFT POS SW2 ● A/T selector lever

“N” position
4WD shift switch: 4LO OFF
● Brake pedal
depressed

Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)
● Vehicle stopped 4WD shift switch: 4H,
0V
● Engine running AUTO or 2WD
27 (W/L) ● A/T selector
- Ground lever “N” position Battery
4WD shift switch: 4LO
● Brake pedal voltage SDIA2715E
depressed
E143
● Vehicle stopped 4WD shift switch: 4LO 0V
● Engine running
44 (LG/B) ● A/T selector
- Ground 4WD shift switch: Battery
lever “N” position
2WD, AUTO or 4H voltage
● Brake pedal
depressed
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND ACTUATOR POSITION SWITCH A
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the transfer control device (actuator position
switch) harness connector. B
3. Check continuity between the following terminals.
– Transfer control unit harness connector E143 terminal 27 (W/L)
and transfer control device (actuator position switch) harness C
connector F58 terminal 23 (W/L).
– Transfer control unit harness connector E143 terminal 44 (LG/B)
and transfer control device (actuator position switch) harness TF
connector F58 terminal 20 (LG/B).
Continuity should exist.
E
Also check harness for short to ground and short to power.
OK or NG SDIA2716E

OK >> GO TO 3.
F
NG >> Repair or replace damaged parts.

3. CHECK GROUND CIRCUIT

G
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control device (actuator position switch) harness connector.
3. Check continuity between transfer control device (actuator posi- H
tion switch) harness connector F58 terminal 22 (B) and ground.
Continuity should exist.
I
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4. J
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.

SDIA2717E K

4. CHECK ACTUATOR POSITION SWITCH

L
1. Remove transfer control device. Refer to TF-138, "Removal and Installation" .
2. Check operation by applying battery voltage to transfer control
device (actuator motor) terminals 21 and 24.
M
CAUTION:
● Do not operate actuator motor for more than 1 second.

● Change the actuator motor position to “HIGH” when

installing.
● Be careful not to overheat the harness.

Terminal Continuity Continuity

24 (Battery voltage) - 21 20 - 22 Yes LDIA0101E

(Ground) 22 - 23 No

21 (Battery voltage) - 24 22 - 23 Yes

(Ground) 20 - 22 No

OK or NG
YES >> GO TO 5.
NO >> Replace transfer control device (actuator motor). Refer to TF-138, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

5. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

6. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control device. Refer to TF-138, "Removal and Installation" .
COMPONENT INSPECTION
1. Remove transfer control device. Refer to TF-138, "Removal and Installation" .
2. Check operation by applying battery voltage to transfer control
device (actuator motor) terminals 21 and 24.
CAUTION:
● Do not operate actuator motor for more than 1 second.

● Change the actuator motor position to “HIGH” when

installing.
● Be careful not to overheat the harness.

Terminal Continuity Continuity

24 (Battery voltage) - 21 20 - 22 Yes LDIA0101E

(Ground) 22 - 23 No

21 (Battery voltage) - 24 22 - 23 Yes

(Ground) 20 - 22 No

3. If NG, replace transfer control device (actuator motor). Refer to TF-138, "Removal and Installation" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

Transfer Control Device EDS002IE

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE A

Data are reference value.
Monitored item [Unit] Content Condition Display value
● Vehicle stopped 4WD shift switch: 4H to B
● Engine running 4LO (“Wait” function is ON
SHIFT AC MON1 [ON/ Check signal for transfer operating.)
OFF] control unit signal output ● A/T selector lever “N”
position C
Except the above OFF
● Brake pedal depressed
● Vehicle stopped 4WD shift switch: 4LO to
● Engine running 4H (“Wait” function is ON TF
SHIFT AC MON2 [ON/ Check signal for transfer operating.)
OFF] control unit signal output ● A/T selector lever “N”
position
Except the above OFF
● Brake pedal depressed E
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
Wire F
Terminal Item Condition Data (Approx.)
color
Ignition switch: ON Battery voltage
16 Y/R Power supply
Ignition switch: OFF 0V G
Ignition switch: ON Battery voltage
22 Y/R Power supply
Ignition switch: OFF 0V
H
Ignition switch: ON 0V
30 SB Shut off relay
Ignition switch: OFF Battery voltage
● Vehicle stopped 4WD shift switch: 4H to 4LO (“Wait” func- I
Battery voltage
● Engine running tion is operating.)
Transfer shift high relay moni- ● A/T selector
33 R/L
tor lever “N” position J
Except the above 0V
● Brake pedal
depressed
● Vehicle stopped 4WD shift switch: 4LO to 4H (“Wait” func- K
Battery voltage
● Engine running tion is operating.)
Transfer shift low relay moni- ● A/T selector
42 P/G
tor lever “N” position
Except the above 0V L
● Brake pedal
depressed
CAUTION: M
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
1. CHECK POWER SUPPLY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Connect transfer control unit harness connector.
3. Check voltage between transfer control unit harness connector
terminal and ground.
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142 0V
22 (Y/R) - Ground
E143 30 (SB) - Ground Battery voltage

SDIA2834E

4. Turn ignition switch “ON”. (Do not start engine.)

5. Check voltage between transfer control unit harness connector
terminals and ground.
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142 Battery voltage
22 (Y/R) - Ground
E143 30 (SB) - Ground 0V

OK or NG
OK >> GO TO 2. SDIA2835E

NG >> Check the following. If any items are damaged, repair or

replace damaged parts.
● 10A fuse No. 26 located in the fuse and fusible link box. Refer to PG-4, "POWER SUPPLY
ROUTING CIRCUIT" .
● Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 1 (G).
● Harness for short or open between transfer shut off relay harness connector E69 terminal 2
(SB) and transfer control unit harness connector E143 terminal 30 (SB).
● Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 3 (G).
● Harness for short or open between transfer shut off relay harness connector E69 terminal 5 (Y/
R) and transfer control unit harness connector E142 terminal 22 (Y/R).
● Transfer shut off relay. Refer to TF-57, "COMPONENT INSPECTION" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK GROUND CIRCUIT A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec- B
tor E142 terminals 3 (B), 6 (B), E143 terminal 45 (B) and ground.
Continuity should exist.
C
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3. TF
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
E
SDIA2691E

3. CHECK ACTUATOR MOTOR POWER SUPPLY CIRCUIT

F
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "Location of Electrical Parts" .
3. Check voltage between transfer shift high relay harness connec- G
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
Connector Terminal (Wire color) Voltage (Approx.) H
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground
I

SDIA2707E J

4. Turn ignition switch “ON”. (Do not start engine.)

5. Check voltage between transfer shift high relay harness connec- K
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
Connector Terminal (Wire color) Voltage (Approx.) L
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground
M
OK or NG
OK >> GO TO 4. SDIA2706E

NG >> Check the following. If any items are damaged, repair or

replace damaged parts.
● 20A fuse No. 57 located in the fuse and relay box. Refer to PG-4, "POWER SUPPLY ROUTING
CIRCUIT" .
● Harness for short or open between battery, transfer shift high relay harness connector E46 ter-
minal 5 (R) and transfer shift low relay harness connector E47 terminal 5 (R).

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 TROUBLE DIAGNOSIS FOR SYSTEM

4. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER SHIFT RELAY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and transfer control device (actuator motor) harness
connector.
3. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "Location of Electrical Parts" .
4. Check continuity between the following terminals.
– Transfer control unit harness connector E143 terminal 33 (R/L)
and transfer shift high relay harness connector E46 terminal 3
(R/L).
– Transfer control unit harness connector E143 terminal 42 (P/G)
and transfer shift low relay harness connector E47 terminal 3 (P/
G).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5. SDIA2712E

NG >> Repair or replace damaged parts.

5. CHECK TRANSFER SHIFT RELAY GROUND CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay.
3. Check continuity between transfer shift high relay harness con-
nector E46 terminals 1 (B/W), 4 (B), transfer shift low relay har-
ness connector E47 terminal 1 (B/W), 4 (B) and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
SDIA2708E

6. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK-1 >> With CONSULT-II: GO TO 7.
OK-2 >> Without CONSULT-II: GO TO 8.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

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 TROUBLE DIAGNOSIS FOR SYSTEM

7. PERFORM SELF-DIAGNOSIS (WITH CONSULT-II) A

With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
B
2. Select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE”.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
C
5. Perform the self-diagnosis again.
Is the “SHIFT ACT CIR [P1819]” displayed?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" . TF
NO >> Inspection End.

8. PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-II) E

Without CONSULT-II
1. Perform the self-diagnosis and then erase self-diagnostic results. Refer to TF-50, "SELF-DIAGNOSTIC
PROCEDURE (WITHOUT CONSULT-II)" and TF-53, "ERASE SELF-DIAGNOSIS" . F
2. Perform the self-diagnosis again.
Do the self-diagnostic results indicate transfer control device?
G
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
Engine Speed Signal (ECM) EDS002IF H
DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ECM
I
Perform self-diagnosis with ECM. Refer to EC-130, "SELF-DIAG RESULTS MODE" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system. J
NO >> GO TO 2.

2. CHECK TRANSFER CONTROL UNIT K

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG L
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts. M

3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ECM again. Refer to EC-130, "SELF-DIAG RESULTS MODE" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

Clutch Pressure Solenoid EDS002IG

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Monitored item Content Condition Display value
● Vehicle stopped 4WD shift switch: 2WD 4%
● Engine running 4WD shift switch: AUTO 96 - 4%
Condition of clutch pres-
DUTY SOLENOID [%] ● A/T selector lever “N”
sure solenoid
position 4WD shift switch: 4H or
4%
4LO
● Brake pedal depressed

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
● Vehicle stopped 4WD shift switch: AUTO 4 - 14V
● Engine running

10 L/W Transfer dropping resistor ● A/T selector

lever “N” position 4WD shift switch: 2WD, 4H or 4LO Less than 1V
● Brake pedal
depressed
● Vehicle stopped 4WD shift switch: AUTO 1.5 - 3V
● Engine running
Clutch pressure solenoid ● A/T selector
19 L
valve lever “N” position 4WD shift switch: 2WD, 4H or 4LO Less than 1V
● Brake pedal
depressed
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK CLUTCH PRESSURE SIGNAL
With CONSULT-II
B
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “DUTY SOLENOID”.
C
Condition Display value
● Vehicle stopped 4WD shift switch: 2WD 4%
● Engine running
TF
4WD shift switch: AUTO 96 - 4%
● A/T selector lever “N” position 4WD shift switch: 4H or
4%
● Brake pedal depressed 4LO
E

SDIA2718E
F

Without CONSULT-II
1. Start engine. G
2. Check voltage between transfer control unit harness connector
terminal and ground.
Terminal H
Voltage
Connector (Wire Condition
(Approx.)
color)
● Vehicle stopped 4WD shift switch:
4 - 14V
I
● Engine running AUTO
10 (L/W) ● A/T selector lever
- Ground “N” position 4WD shift switch: Less J
● Brake pedal 2WD, 4H or 4LO than 1V SDIA2719E
depressed
E142
● Vehicle stopped 4WD shift switch: K
1.5 - 3V
● Engine running AUTO
19 (L) - ● A/T selector lever
Ground “N” position 4WD shift switch: Less L
● Brake pedal 2WD, 4H or 4LO than 1V
depressed
OK or NG M
OK >> GO TO 7.
NG >> GO TO 2.

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND CLUTCH PRESSURE SOLENOID
VALVE
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector, transfer terminal cord assembly harness connector
and transfer dropping resistor.
3. Check continuity between transfer control unit harness connec-
tor E142 terminal 19 (L) and transfer terminal cord assembly
harness connector F56 terminal 6 (L).
Continuity should exist.

SDIA2720E

4. Check continuity between transfer dropping resistor harness

connector E135 terminal 2 (L) and transfer terminal cord assem-
bly harness connector F56 terminal 6 (L).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

SDIA2721E

3. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER DROPPING RESISTOR
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and transfer dropping resistor harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminal 10 (L/W) and transfer dropping resistor har-
ness connector E135 terminal 1 (L/W).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.

SDIA2722E

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 TROUBLE DIAGNOSIS FOR SYSTEM

4. CHECK GROUND CIRCUIT A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check continuity between transfer terminal cord assembly har- B
ness connector F56 terminal 19 (B) and ground.
Continuity should exist.
C
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5. TF
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
E
SDIA2723E

5. CHECK CLUTCH PRESSURE SOLENOID

F
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter- G
minals 6 and 19.
6 - 19 : Approx. 3.0 - 3.4 Ω
H
OK or NG
OK >> GO TO 6.
NG >> Replace clutch pressure solenoid. Refer to TF-22,
"Location of Electrical Parts" . I

WDIA0225E J

6. CHECK TRANSFER DROPPING RESISTOR

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) K
2. Disconnect transfer dropping resistor harness connector. Refer to TF-22, "Location of Electrical Parts" .
3. Check resistance between transfer dropping resistor terminals 1
L
and 2.
1-2 : Approx. 11.2 - 12.8 Ω
OK or NG M
OK >> GO TO 7.
NG >> Replace transfer dropping resistor. Refer to TF-22,
"Location of Electrical Parts" .

SDIA2725E

7. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 8.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

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 TROUBLE DIAGNOSIS FOR SYSTEM

8. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
COMPONENT INSPECTION
Clutch Pressure Solenoid
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter-
minals 6 and 19.
6 - 19 : Approx. 3.0 - 3.4 Ω
4. If NG, replace clutch pressure solenoid. Refer to TF-22, "Loca-
tion of Electrical Parts" .

WDIA0225E

Transfer Dropping Resistor

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer dropping resistor harness connector.
3. Check resistance between transfer dropping resistor terminals 1
and 2.
1-2 : Approx. 11.2 - 12.8 Ω
4. If NG, replace transfer dropping resistor. Refer to TF-22, "Loca-
tion of Electrical Parts" .

SDIA2725E

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 TROUBLE DIAGNOSIS FOR SYSTEM

2-4WD Solenoid EDS002IH

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE A

Data are reference value.
Monitored item Content Condition Display value
4WD shift switch: 2WD OFF B
4WD shift switch: AUTO

● Vehicle stopped 4WD shift switch: 4H ON

C
● Engine running 4WD shift switch: 4LO
Condition of 2-4WD shift
2-4WD SOL [ON/OFF] ● A/T selector lever “N” 4WD shift switch: AUTO
solenoid valve
position (“Wait” function is operat- OFF
ing.) TF
● Brake pedal depressed
4WD shift switch: 4H
(“Wait” function is operat- OFF
ing.) E
4WD shift switch: 2WD OFF
4WD shift switch: AUTO
F
● Vehicle stopped 4WD shift switch: 4H ON

● Engine running 4WD shift switch: 4LO

2-4WD SOL MON [ON/ Check signal for transfer
OFF] control unit signal output ● A/T selector lever “N” 4WD shift switch: AUTO G
position (“Wait” function is operat- OFF
● Brake pedal depressed ing.)
4WD shift switch: 4H
H
(“Wait” function is operat- OFF
ing.)

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE I

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
J
● Vehicle stopped 4WD shift switch: 2WD 0V
● Engine running

1 GR 2-4WD shift solenoid valve ● A/T selector

lever “N” position 4WD shift switch: AUTO, 4H or 4LO Battery voltage K
● Brake pedal
depressed
CAUTION: L
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

DIAGNOSTIC PROCEDURE
M
1. CHECK 4WD SHIFT SWITCH SYSTEM
Perform self-diagnosis. Refer to TF-50, "Self-diagnostic Procedure" .
Is the "4WD MOD SW [P1814]" (with CONSULT-II) or "Flickering pattern: 16 (without CONSULT-II) detected?
YES >> Perform trouble diagnosis for 4WD shift switch. Refer to TF-62, "4WD Shift Switch" .
NO >> GO TO 2.

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK 2-4WD SHIFT SOLENOID SIGNAL

With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “2-4WD SOL” and “2-4WD SOL MON”.
Monitored Display
Condition
item value
4WD shift switch: 2WD OFF
4WD shift switch: AUTO
● Vehicle stopped
4WD shift switch: 4H ON
● Engine running
● A/T selector lever “N” 4WD shift switch: 4LO
2-4WD SOL
position 4WD shift switch: AUTO
● Brake pedal (“Wait” function is operat- OFF SDIA2727E

depressed ing.)
4WD shift switch: 4H (“Wait”
OFF
function is operating.)
4WD shift switch: 2WD OFF
4WD shift switch: AUTO
● Vehicle stopped
4WD shift switch: 4H ON
● Engine running
2-4WD SOL ● A/T selector lever “N” 4WD shift switch: 4LO
MON position 4WD shift switch: AUTO
● Brake pedal (“Wait” function is operat- OFF
depressed ing.)
4WD shift switch: 4H (“Wait”
OFF
function is operating.)

Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)
● Vehicle stopped 4WD shift switch:
0V
● Engine running 2WD
1 (GR) - ● A/T selector lever
E142
Ground “N” position 4WD shift switch: Battery
● Brake pedal AUTO, 4H or 4LO voltage SDIA2728E
depressed

OK or NG
OK >> GO TO 7.
NG >> GO TO 3.

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK 4WD SHIFT SWITCH SIGNAL A

1. Turn ignition switch “ON”. (Do not start engine.)
2. Check voltage between transfer control unit harness connector
terminals and ground. B

Terminal Voltage
Connector Condition
(Wire color) (Approx.)
C
4 (G/R) - 4WD shift switch: AUTO, 4H or 4LO Battery voltage
M141
ground 4WD shift switch: 2WD 0V

TF

SDIA2729E
E
OK or NG
OK >> GO TO 4.
NG >> Check 4WD shift switch. Refer to TF-66, "COMPONENT INSPECTION" . F

4. CHECK HARNESS BETWEEN 4WD SHIFT SWITCH AND TRANSFER TERMINAL CORD ASSEMBLY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) G
2. Disconnect 4WD shift switch harness connector and transfer terminal cord assembly harness connector.
3. Check continuity between 4WD shift switch harness connector H
M141 terminal 4 (G/R) and transfer terminal cord assembly har-
ness connector F56 terminal 5 (G/R).
Continuity should exist.
I
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5. J
NG >> Repair or replace damaged parts.

SDIA2731E
K
5. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER TERMINAL CORD
ASSEMBLY
L
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and transfer terminal cord assembly harness connec-
tor. M
3. Check continuity between transfer control unit harness connec-
tor E142 terminal 1 (GR) and transfer terminal cord assembly
harness connector F56 terminal 4 (GR).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.

SDIA2732E

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 TROUBLE DIAGNOSIS FOR SYSTEM

6. CHECK 2-4WD SOLENOID

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter-
minals 4 and 5.
4-5 : Approx. 22.8 - 25.2 Ω
OK or NG
OK >> GO TO 7.
NG >> 2-4WD solenoid is malfunctioning. Refer to TF-22,
"Location of Electrical Parts" .

WDIA0187E

7. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 8.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

8. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter-
minals 4 and 5.
4-5 : Approx. 22.8 - 25.2 Ω
4. If NG, replace the 2-4WD solenoid. Refer to TF-22, "Location of
Electrical Parts" .

WDIA0187E

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 TROUBLE DIAGNOSIS FOR SYSTEM

Transfer Motor EDS002II

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE A

Data are reference value.
Monitored item Content Condition Display value
4WD shift switch: 2WD OFF B
OFF
4WD shift switch: AUTO
("ON" for approx. 2
or 4LO (A/T selector lever
sec. after shifting to C
“P” or “N” position)
“P” and “N”.)
● Accelerator pedal 4WD shift switch: AUTO
depressed or 4LO (Except for A/T
MOTOR RELAY [ON/ Condition of transfer motor selector lever “P” or “N”
ON TF
● Vehicle stopped
OFF] relay position)
● Engine running
OFF
● Brake pedal depressed 4WD shift switch: 4H (A/T
("ON" for approx. 2 E
selector lever “P” posi-
sec. after shifting to
tion)
“P”.)
4WD shift switch: 4H F
(Except for A/T selector ON
lever “P” position)
4WD shift switch: 2WD OFF
G
OFF
4WD shift switch: AUTO
("ON" for approx. 2
or 4LO (A/T selector lever
sec. after shifting to
“P” or “N” position) H
“P” and “N”.)
● Accelerator pedal 4WD shift switch: AUTO
depressed or 4LO (Except for A/T
ON
MOTOR RELAY MON Check signal for transfer ● Vehicle stopped selector lever “P” or “N” I
[ON/OFF] control unit signal output position)
● Engine running
OFF
● Brake pedal depressed 4WD shift switch: 4H (A/T
("ON" for approx. 2
selector lever “P” posi- J
sec. after shifting to
tion)
“P”.)
4WD shift switch: 4H
(Except for A/T selector ON K
lever “P” position)

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 TROUBLE DIAGNOSIS FOR SYSTEM

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
4WD shift switch: 2WD Battery voltage
Battery voltage
(0V for approx.
4WD shift switch: AUTO or 4LO (A/T
2 sec. after
selector lever “P” or “N” position)
● Accelerator shifting to “P”
pedal depressed and “N”.)
● Vehicle stopped 4WD shift switch: AUTO or 4LO (Except
14 LG Transfer motor relay 0V
● Engine running for A/T selector lever “P” or “N” position)
● Brake pedal Battery voltage
depressed 4WD shift switch: 4H (A/T selector lever (0V for approx.
“P” position) 2 sec. after
shifting to “P”.)
4WD shift switch: 4H (Except for A/T
0V
selector lever “P” position)
4WD shift switch: 2WD 0V
0V
(Battery volt-
4WD shift switch: AUTO or 4LO (A/T age for approx.
selector lever “P” or “N” position) 2 sec. after
● Accelerator shifting to “P”
pedal depressed and “N”.)
● Vehicle stopped 4WD shift switch: AUTO or 4LO (Except
41 R Transfer motor relay monitor Battery voltage
● Engine running for A/T selector lever “P” or “N” position)
● Brake pedal 0V
depressed (Battery volt-
4WD shift switch: 4H (A/T selector lever
age for approx.
“P” position)
2 sec. after
shifting to “P”.)
4WD shift switch: 4H (Except for A/T
Battery voltage
selector lever “P” position)
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK TRANSFER MOTOR RELAY SIGNAL
With CONSULT-II
B
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “MOTOR RELAY” and “MOTOR RELAY
C
MON”.
Monitored Display value
Condition
item (Approx.) TF
4WD shift switch: 2WD OFF
OFF
4WD shift switch: AUTO or ("ON" for E
4LO (A/T selector lever “P” or approx. 2 sec.
“N” position) after shifting to
“P” and “N”.)
● Accelerator SDIA2734E
F
pedal depressed 4WD shift switch: AUTO or
● Vehicle stopped 4LO (Except for A/T selector ON
MOTOR
lever “P” or “N” position)
RELAY ● Engine running
OFF G
● Brake pedal
("ON" for
depressed 4WD shift switch: 4H (A/T
approx. 2 sec.
selector lever “P” position)
after shifting to
H
“P”.)
4WD shift switch: 4H (Except
for A/T selector lever “P” posi- ON
tion) I
4WD shift switch: 2WD OFF
OFF
4WD shift switch: AUTO or ("ON" for J
4LO (A/T selector lever “P” or approx. 2 sec.
“N” position) after shifting to
“P” and “N”.)
● Accelerator K
pedal depressed 4WD shift switch: AUTO or
MOTOR ● Vehicle stopped 4LO (Except for A/T selector ON
RELAY lever “P” or “N” position)
MON ● Engine running L
OFF
● Brake pedal
("ON" for
depressed 4WD shift switch: 4H (A/T
approx. 2 sec.
selector lever “P” position)
after shifting to M
“P”.)
4WD shift switch: 4H (Except
for A/T selector lever “P” posi- ON
tion)

Without CONSULT-II
1. Start engine.

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. Check voltage between transfer control unit harness connector

terminal and ground.
Terminal
Connector (Wire Condition Voltage (Approx.)
color)
4WD shift switch:
Battery voltage
2WD
4WD shift switch: Battery voltage
AUTO or 4LO (A/T (0V for approx. 2
selector lever “P” or sec. after shifting
● Accelera- SDIA2735E
“N” position) to “P” and “N”.)
tor pedal
depressed 4WD shift switch:
● Vehicle AUTO or 4LO
stopped (Except for A/T 0V
14 (LG) -
E142 selector lever “P” or
Ground ● Engine “N” position)
running
Battery voltage
● Brake 4WD shift switch:
(0V for approx. 2
pedal 4H (A/T selector
sec. after shifting
depressed lever “P” position)
to “P”.)
4WD shift switch:
4H (Except for A/T
0V
selector lever “P”
position)
4WD shift switch:
0V
2WD
0V
4WD shift switch:
(Battery voltage
AUTO or 4LO (A/T
for approx. 2 sec.
selector lever “P” or
after shifting to
● Accelera- “N” position)
“P” and “N”.)
tor pedal
depressed 4WD shift switch:
● Vehicle AUTO or 4LO
stopped (Except for A/T Battery voltage
41 (R) -
E143 selector lever “P” or
Ground ● Engine “N” position)
running
0V
● Brake
4WD shift switch: (Battery voltage
pedal
4H (A/T selector for approx. 2 sec.
depressed
lever “P” position) after shifting to
“P”.)
4WD shift switch:
4H (Except for A/T
Battery voltage
selector lever “P”
position)

OK or NG
OK >> GO TO 7.
NG >> GO TO 2.

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 TROUBLE DIAGNOSIS FOR SYSTEM

2. CHECK TRANSFER MOTOR RELAY POWER SUPPLY CIRCUIT A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Connect transfer control unit harness connector.
3. Disconnect transfer motor relay. B
4. Check voltage between transfer motor relay harness connector
terminals and ground.
C
Connector Terminal (Wire color) Voltage (Approx.)
E153 2 (Y/R) - Ground 0V
E154 5 (G/R) - Ground Battery voltage TF

WDIA0169E

5. Turn ignition switch “ON”. (Do not start engine.) F

6. Check voltage between transfer motor relay harness connector
terminals and ground.
G
Connector Terminal (Wire color) Voltage (Approx.)
E153 2 (Y/R) - Ground
Battery voltage
E154 5 (G/R) - Ground H
OK or NG
OK >> GO TO 3.
NG >> Check the following. If any items are damaged, repair or WDIA0170E
I
replace damaged parts.
● 20A fuse No. 58 located in the fuse and relay box. Refer to PG-4, "POWER SUPPLY ROUTING
CIRCUIT" . J
● 10A fuse No. 26 located in the fuse and fusible link box. Refer to PG-4, "POWER SUPPLY
ROUTING CIRCUIT"
● Harness for short or open between battery and transfer motor relay harness connector E154 K
terminal 5 (G/R).
● Harness for short or open between transfer shut off relay harness connector E69 terminal 5 (Y/
R) and transfer motor relay harness connector E153 terminal 2 (Y/R). L
● Battery and ignition switch. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .

3. CHECK TRANSFER MOTOR RELAY M

1. Turn ignition switch “OFF”.

2. Remove transfer motor relay. Refer to TF-22, "Location of Electrical Parts" .
3. Apply 12V direct current between transfer motor relay terminals
1 and 2.
4. Check continuity between relay terminals 3 and 5.
Condition Continuity
12V direct current supply between terminals 1 and 2 Yes
OFF No
OK or NG
OK >> GO TO 4.
NG >> Replace the transfer motor relay. LDIA0098E

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 TROUBLE DIAGNOSIS FOR SYSTEM

4. CHECK TRANSFER MOTOR CONTROL CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer motor relay. Refer to TF-22, "Location of Electrical Parts" .
3. Disconnect transfer control unit harness connector and transfer motor.
4. Check continuity between the following terminals.
– Transfer control unit harness connector E142 terminal 14 (LG)
and transfer motor relay harness connector E153 terminal 1
(LG).

SDIA2738E

– Transfer control unit harness connector E142 terminal 41 (R)

and transfer motor relay harness connector E154 terminal 3 (R).
– Transfer control unit harness connector E142 terminal 41 (R)
and transfer motor harness connector F57 terminal 14 (R).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
WDIA0143E

5. CHECK TRANSFER MOTOR GROUND CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer motor harness connector.
3. Check continuity between transfer motor harness connector F57
terminal 15 (B) and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.

SDIA2740E

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 TROUBLE DIAGNOSIS FOR SYSTEM

6. CHECK TRANSFER MOTOR A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer motor harness connector.
3. Apply 12V direct current between transfer motor terminals 14 B
and 15.
Does transfer motor operate?
YES >> GO TO 7. C
NO >> Replace transfer motor. Refer to TF-140, "Removal and
Installation" .
TF

E
LDIA0097E

7. CHECK TRANSFER CONTROL UNIT

F
Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG G
OK >> GO TO 8.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
H
8. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while. I
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" . J

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 TROUBLE DIAGNOSIS FOR SYSTEM

COMPONENT INSPECTION
Transfer Motor Relay
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer motor relay. Refer to TF-22, "Location of Electrical Parts" .
3. Apply 12V direct current between transfer motor relay terminals
1 and 2.
4. Check continuity between relay terminals 3 and 5.
Condition Continuity
12V direct current supply between terminals 1 and 2 Yes
OFF No

5. If NG, replace transfer motor relay. Refer to TF-22, "Location of

Electrical Parts" .
LDIA0098E

Transfer Motor
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer motor. Refer to TF-140, "Removal and Installation" .
3. Apply 12V direct current between transfer motor terminals 14
and 15.
4. If transfer motor does not operate, replace transfer motor. Refer
to TF-140, "Removal and Installation" .

LDIA0097E

Transfer Fluid Temperature EDS002IJ

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Display value
Monitored item [Unit] Content Condition
(Approx.)
Condition of transfer fluid Transfer fluid temperature approx. 20 - 80°C (68 -
FLUID TEMP SE [V] 1.1 - 0.3V
temperature 176°F)

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
28 B/G Sensor ground Always 0V
Transfer fluid temperature approx. 20°C
1.1V
Transfer fluid temperature (68°F)
31 G Ignition switch: ON
sensor Transfer fluid temperature approx. 80°C
0.3V
(176°F)
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK TRANSFER FLUID TEMPERATURE SENSOR SIGNAL
With CONSULT-II
B
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “FLUID TEMP SE”.
C
Display value
Condition
(Approx.)
Transfer fluid temperature approx. 20 - 80°C (68 - 176°F) 1.1 - 0.3V TF

SDIA2741E
F

Without CONSULT-II
1. Start engine. G
2. Check voltage between transfer control unit harness connector
terminals and ground.
Terminal H
Data
Connector (Wire Condition
(Approx.)
color)
28 (B/G)
Always 0V
I
- Ground
Transfer fluid temperature
E143 1.1V
31 (G) - Ignition switch: approx. 20°C (68°F) J
Ground ON Transfer fluid temperature SDIA2742E
0.3V
approx. 80°C (176°F)

OK or NG K
OK >> GO TO 4.
NG >> GO TO 2.
L
2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER TERMINAL CORD
ASSEMBLY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) M
2. Disconnect transfer control unit harness connector and transfer terminal cord assembly harness connec-
tor.
3. Check continuity between the following terminals.
– Transfer control unit harness connector E143 terminal 28 (B/G)
and transfer terminal cord assembly harness connector F56 ter-
minal 3 (B/G).
– Transfer control unit harness connector E143 terminal 31 (G)
and transfer terminal cord assembly harness connector F56 ter-
minal 2 (G).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG SDIA2743E

OK >> GO TO 3.
NG >> Repair or replace damaged parts.

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK TRANSFER FLUID TEMPERATURE SENSOR

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter-
minals 2 and 3.
Temperature °C (°F) Resistance (Approx.)
20 (68) 2.5 kΩ
80 (176) 0.3 kΩ

OK or NG
OK >> GO TO 4.
NG >> Replace transfer fluid temperature sensor. Refer to TF-
22, "Location of Electrical Parts" . WDIA0188E

4. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 5.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

5. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly har-
ness connector F56 terminals 2 and 3.
Temperature °C (°F) Resistance (Approx.)
20 (68) 2.5 kΩ
80 (176) 0.3 kΩ
4. If NG, replace the transfer fluid temperature sensor. Refer to TF-
22, "Location of Electrical Parts" .

WDIA0188E

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 TROUBLE DIAGNOSIS FOR SYSTEM

Clutch Pressure Switch EDS002IK

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE A

Data are reference value.
Monitored item [Unit] Content Condition Display value
● Vehicle stopped B
● Engine running
● A/T selector lever “D” position ON
● 4WD shift switch: AUTO or 4H (“Wait” function is not C
CL PRES SW [ON / Condition of clutch pres- operating.)
OFF] sure switch
● Vehicle stopped
● Engine running TF
OFF
● 4WD shift switch: 2WD (“Wait” function is not oper-
ating.)
E
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color F
● Vehicle stopped
● Engine running 4WD shift switch: AUTO or 4H (“Wait”
0V
● A/T selector function is not operating.) G
34 BR Clutch pressure switch
lever “D” position
● Vehicle stopped 4WD shift switch: 2WD (“Wait” function is
Battery voltage
● Engine running not operating.) H
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.
I

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
1. CHECK CLUTCH PRESSURE SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out ON/OFF switching action of the “CL PRES SW” while
operating 4WD shift switch.
Condition Display value
● Ignition switch: ON
4WD shift switch: AUTO or 4H
● A/T selector lever “D” ON
(“Wait” function is not operating.)
position
4WD shift switch: 2WD (“Wait”
Ignition switch: ON OFF
function is not operating.)

Without CONSULT-II
WDIA0141E
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminals and ground.
Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)

● Ignition switch: ON 4WD shift switch:

AUTO or 4H
● A/T selector lever 0V
(“Wait” function is
“D” position not operating.)
34 (BR) -
E143
Ground 4WD shift switch:
SDIA2746E
2WD (“Wait” func- Battery
Ignition switch: ON
tion is not operat- voltage
ing.)

OK or NG
OK >> GO TO 5.
NG >> GO TO 2.

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND CLUTCH PRESSURE SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the transfer terminal cord assembly harness con-
nector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 34 (BR) and transfer terminal cord assembly
harness connector F56 terminal 7 (BR)
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

SDIA2747E

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK TRANSFER CONTROL UNIT A

Check transfer control unit input/output signal. Refer to TF-54, "TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG B
OK >> GO TO 4.
NG >> Check transfer control unit pin terminals for damage or loose connection with the harness connec-
tor. If any items are damaged, repair or replace damaged parts. C

4. CHECK CLUTCH PRESSURE SWITCH

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) TF
2. Remove clutch pressure switch. Refer to TF-22, "Location of Electrical Parts" .
3. Push and release clutch pressure switch and check continuity
between transfer terminal cord assembly terminal 7 and ground. E

Terminal Condition Continuity

7- Push clutch pressure switch Yes F

Ground Release clutch pressure switch No
OK or NG
G
OK >> GO TO 5.
NG >> Replace clutch pressure switch. Refer to TF-22, "Loca-
tion of Electrical Parts" . WDIA0171E
H
5. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while. I
OK or NG
OK >> GO TO 6.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" . J

6. CRUISE TEST
Perform cruise test. Refer to TF-34, "CRUISE TEST" . K
OK or NG
OK >> Inspection End.
NG >> Perform the applicable trouble diagnosis. L

COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) M
2. Remove clutch pressure switch. Refer to TF-22, "Location of Electrical Parts" .
3. Push and release clutch pressure switch and check continuity
between transfer terminal cord assembly terminal 7 and ground.
Terminal Condition Continuity
Push clutch pressure switch Yes
7 - Ground
Release clutch pressure switch No
4. If NG, replace the clutch pressure switch. Refer to TF-22, "Loca-
tion of Electrical Parts" .

WDIA0171E

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 TROUBLE DIAGNOSIS FOR SYSTEM

Line Pressure Switch EDS002IL

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE

Data are reference value.
Monitored item [Unit] Content Condition Display value
● A/T selector lever “D” position
ON
● 4WD shift switch: 2WD, AUTO or 4H
● Except the above
● Ignition switch: ON
LINE PRES SW [ON/ Condition of line pressure ● The vehicle has been
OFF] switch left at room tempera- ● A/T selector lever: "P"
ture for 5 minutes and or "N" position OFF
more with ignition ● 4WD shift switch: other
switch in “OFF” posi- than AUTO
tion.

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground.
Wire
Terminal Item Condition Data (Approx.)
color
● Ignition switch: ON
● A/T selector lever “D” posi- ● 4WD shift switch: AUTO 0V
tion

● Except the above ● Ignition switch: ON

35 BR/W Line pressure switch
● The vehicle has been left at ● A/T selector lever: "P" or "N"
room temperature for 5 min- position Battery voltage
utes and more with ignition ● 4WD shift switch: other than
switch in “OFF” position. AUTO
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
A
1. CHECK LINE PRESSURE SWITCH SIGNAL
With CONSULT-II
B
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out ON/OFF switching action of “LINE PRES SW” while
C
operating 4WD shift switch.
Condition Display value
● A/T selector lever “D” position TF
ON
● 4WD shift switch: AUTO
● Except the above ● Ignition switch: ON
● The vehicle has been left E
● A/T selector lever: "P" or "N"
at room temperature for 5 position OFF
minutes and more with
ignition switch in “OFF” ● 4WD shift switch: other than
WDIA0142E
AUTO F
position.

Without CONSULT-II
1. Start engine. G
2. Check voltage between transfer control unit harness connector
terminals and ground.
H
Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)
● A/T selector lever 4WD shift switch: I
0V
“D” position AUTO
● Ignition switch:
● Except the above ON J
35 (BR/ ● The vehicle has
E143 W) - ● A/T selector SDIA2751E
been left at room lever: "P" or "N" Battery
Ground temperature for 5 position voltage
minutes and more K
with ignition switch ● 4WD shift
in “OFF” position. switch: other
than AUTO
L
OK or NG
OK >> GO TO 5.
NG >> GO TO 2. M

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND LINE PRESSURE SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the transfer terminal cord assembly harness con-
nector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 35 (BR/W) and transfer terminal cord assem-
bly harness connector F56 terminal 1 (BR/W).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

SDIA2752E

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
● Transfer control unit pin terminals for damage or loose connection with harness connector.

● Transfer control unit. Refer to TF-132, "Removal and Installation" .

4. CHECK LINE PRESSURE SWITCH

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove line pressure switch. Refer to TF-22, "Location of Electrical Parts" .
3. Push and release line pressure switch and check continuity
between transfer terminal cord assembly terminal 1 and ground.
Terminal Condition Continuity

1- Push line pressure switch Yes

Ground Release line pressure switch No

OK or NG
OK >> GO TO 5.
NG >> Replace line pressure switch. Refer to TF-22, "Location
of Electrical Parts" . WDIA0172E

5. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> GO TO 6.
NG >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .

6. CRUISE TEST
Perform cruise test. Refer to TF-34, "CRUISE TEST" .
OK or NG
OK >> INSPECTION END.
NG >> Perform the applicable trouble diagnosis.
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove line pressure switch. Refer to TF-22, "Location of Electrical Parts" .
3. Push and release line pressure switch and check continuity
between transfer terminal cord assembly terminal 1 and ground.
Terminal Condition Continuity
Push line pressure switch Yes
1 - Ground
Release line pressure switch No
4. If NG, replace the line pressure switch. Refer to TF-22, "Loca-
tion of Electrical Parts" .

WDIA0172E

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 TROUBLE DIAGNOSIS FOR SYSTEM

Throttle Position Signal (ECM) EDS002IM

DIAGNOSTIC PROCEDURE A

1. CHECK DTC WITH ECM

Perform self-diagnosis with ECM. Refer to EC-130, "SELF-DIAG RESULTS MODE" . B
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2. C

2. CHECK TRANSFER CONTROL UNIT

TF
Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
E
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
F
3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while. G
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ECM again. Refer to EC-130, "SELF-DIAG RESULTS MODE" . H
ABS Operation Signal (ABS) EDS002IN

DIAGNOSTIC PROCEDURE
I
1. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-29, "SELF-DIAGNO-
SIS" . J
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2. K

2. CHECK TRANSFER CONTROL UNIT

L
Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
M
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ABS actuator and electric unit (control unit) again. Refer to BRC-29,
"SELF-DIAGNOSIS" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

VDC Operation Signal (ABS) EDS002IO

DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-29, "SELF-DIAGNO-
SIS" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.

2. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ABS actuator electric unit (control unit) again. Refer to BRC-29,
"SELF-DIAGNOSIS" .
TCS Operation Signal (ABS) EDS002IP

DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-29, "SELF-DIAGNO-
SIS" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.

2. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ABS actuator and electric unit (control unit) again. Refer to BRC-29,
"SELF-DIAGNOSIS" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

CAN Communication Line EDS002IQ

DIAGNOSTIC PROCEDURE A

1. CHECK CAN COMMUNICATION CIRCUIT

With CONSULT-II B
1. Turn ignition switch “ON” and start engine.
2. Select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” within CONSULT-II.
C
3. Perform the self-diagnosis.
Is the “CAN COMM CIRCUIT [U1000]” displayed?
YES >> Print CONSULT-II screen and go to LAN-3, "Precautions TF
When Using CONSULT-II" .
NO >> Inspection End.
E

F
SDIA1850E

ATP Switch EDS002IR

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE G

Data are reference value.
Monitored item [Unit] Content Condition Display value

● Vehicle stopped 4WD shift switch H

: 4H to 4LO or 4LO to 4H
● Engine running ON
ATP SWITCH [ON/OFF] Condition of ATP switch (While actuator motor is
● A/T selector lever “N" operating.)
● Brake pedal depressed I
Except the above OFF

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE

Data are reference value and are measured between each terminal and ground. J
Wire
Terminal Item Condition Data (Approx.)
color
● Vehicle stopped 4WD shift switch: 4H to 4LO or 4LO to 4H
0V K
● Engine running (While actuator motor is operating.)

40 L ATP switch ● A/T selector

lever “N"
Except the above Battery voltage L
● Brake pedal
depressed
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.
M

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 TROUBLE DIAGNOSIS FOR SYSTEM

DIAGNOSTIC PROCEDURE
1. CHECK ATP SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “ATP SWITCH”.
Condition Display value
● Vehicle stopped 4WD shift switch
● Engine running : 4H to 4LO or 4LO to 4H ON
(While actuator motor is operating.)
● A/T selector lever
“N"
● Brake pedal Except the above OFF
depressed

SDIA2391E

Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Terminal
Voltage
Connector (Wire Condition
(Approx.)
color)
● Vehicle stopped 4WD shift switch: 4H
● Engine running to 4LO or 4LO to 4H
0V
(While actuator motor
40 (L) - ● A/T selector lever
E143 is operating.)
Ground “N"
● Brake pedal Battery
Except the above SDIA2755E
depressed voltage

OK or NG
OK >> GO TO 5.
NG >> GO TO 2.

2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND ATP SWITCH

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the ATP switch harness connector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 40 (L) and ATP switch harness connector F55
terminal 8 (L/Y).
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

SDIA2756E

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 TROUBLE DIAGNOSIS FOR SYSTEM

3. CHECK GROUND CIRCUIT A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect ATP switch harness connector.
3. Check continuity between ATP switch harness connector F55 B
terminal 9 (B) and ground.
Continuity should exist.
C
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4. TF
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
E
SDIA2394E

4. CHECK ATP SWITCH

F
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect ATP switch harness connector.
3. Remove ATP switch. Refer to TF-22, "Location of Electrical Parts" . G
4. Push and release ATP switch and check continuity between ATP
switch terminals 8 and 9.
H
Terminal Condition Continuity
Push ATP switch Yes
8-9
Release ATP switch No I
OK or NG
OK >> GO TO 5.
NG >> Replace ATP switch. Refer to TF-22, "Location of Elec- J
trical Parts" . SDIA2757E

5. CHECK TRANSFER CONTROL UNIT K

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
L
OK or NG
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts. M

6. CHECK ATP WARNING LAMP

1. Turn ignition switch “ON”. (Do not start engine.)
2. Move A/T selector lever to "P" position.
3. Set 4WD shift switch from "4H" to "4LO" or "4LO" to "4H".
Does ATP warning lamp turn ON while switching?
YES >> GO TO TF-125, "ATP Warning Lamp Turns ON" .
NO >> Inspection End.
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 second.)
2. Disconnect ATP switch harness connector.
3. Remove ATP switch. Refer to TF-22, "Location of Electrical Parts" .

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 TROUBLE DIAGNOSIS FOR SYSTEM

4. Push and release ATP switch and check continuity between ATP
switch terminals 8 and 9.
Terminal Condition Continuity
Push ATP switch Yes
8-9
Release ATP switch No

5. If NG, replace the ATP switch. Refer to TF-22, "Location of Elec-

trical Parts" .

SDIA2757E

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

TROUBLE DIAGNOSIS FOR SYMPTOMS PFP:00007

A
4WD Shift Indicator Lamp and 4LO Indicator Lamp Do Not Turn ON EDS002HM

SYMPTOM:
4WD shift indicator lamp and 4LO indicator lamp do not turn ON for approx. 1 second when turning B
ignition switch to “ON”.
DIAGNOSTIC PROCEDURE
1. CHECK TRANSFER CONTROL UNIT POWER SUPPLY CIRCUIT C

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)

2. Connect transfer control unit harness connector. TF
3. Check voltage between transfer control unit harness connector
terminals and ground.
E
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142
22 (Y/R) - Ground 0V F
29 (L/W) - Ground
E143 30 (SB) - Ground
Battery voltage G
47 (W) - Ground
WDIA0165E

4. Turn ignition switch “ON”. (Do not start engine.) H

5. Check voltage between transfer control unit harness connector
terminals and ground.
I
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142
22 (Y/R) - Ground Battery voltage J
29 (L/W) - Ground
E143 30 (SB) - Ground 0V
WDIA0166E K
47 (W) - Ground Battery voltage

OK or NG
OK >> GO TO 2. L
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
● 10A fuses No. 26 located in fuse and fusible link box and No. 59 located in the fuse and relay
box. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" . M
● 20A fuse No. 53 located in the IPDM E/R. Refer to PG-4, "POWER SUPPLY ROUTING CIR-
CUIT" .
● Harness for short or open between battery and transfer control unit harness connector termi-
nals 47.
● Harness for short or open between battery and transfer control unit harness connector terminal
29.
● Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 1 (G), and 3 (G).
● Harness for short or open between transfer shut off relay harness connector E69 terminal 2
(SB) and transfer control unit harness connector terminal 30.
● Harness for short or open between transfer shut off relay harness connector E69 terminal 5 (Y/
R) and transfer control unit harness connector terminals 16 (Y/R) and 22 (Y/R).
● Battery and ignition switch. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .

● Transfer shut off relay. Refer to TF-57, "COMPONENT INSPECTION" .

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

2. CHECK TRANSFER CONTROL UNIT GROUND CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminals 3 (B), 6 (B), E143 terminal 45 (B) and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.

SDIA2691E

3. CHECK COMBINATION METER POWER SUPPLY CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect combination meter harness connector.
3. Check voltage between combination meter harness connector
terminal and ground.
Connector Terminal (Wire color) Voltage (Approx.)
M24 24 (O/L) - Ground 0V

WDIA0151E

4. Turn ignition switch “ON”. (Do not start engine.)

5. Check voltage between combination meter harness connector
terminal and ground.
Connector Terminal (Wire color) Voltage (Approx.)
M24 24 (O/L) - Ground Battery voltage
OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or
replace damaged parts. WDIA0152E

● 10A fuse No. 14 located in the fuse block (J/B). Refer

to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .
● Harness for short or open between battery and combination meter harness connector M24 ter-
minal 24 (O/L).
● Ignition switch. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

4. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND COMBINATION METER A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and combination meter harness connector.
3. Check continuity between the following terminals. B
– Transfer control unit harness connector E142 terminal 2 (B/W)
and combination meter harness connector M24 terminal 32 (B/
W). C
– Transfer control unit harness connector E142 terminal 11 (L)
and combination meter harness connector M24 terminal 31 (L).
– Transfer control unit harness connector E142 terminal 12 (W/G) TF
and combination meter harness connector M24 terminal 33 (W/
G).
– Transfer control unit harness connector E142 terminal 21 (BR) E
and combination meter harness connector M24 terminal 30
(BR).
Continuity should exist. F
Also check harness for short to ground and short to power.
OK or NG
G
OK >> GO TO 5.
NG >> Repair or replace damaged parts.

WDIA0160E

I
5. CHECK INDICATOR LAMP CIRCUIT
1. Connect combination meter harness connector.
2. Disconnect transfer control unit harness connector. J
3. Turn ignition switch “ON”.
4. Ground the following terminals using suitable wiring.
K
– Transfer control unit harness connector E142 terminal 2 (B/W)
and ground.
– Transfer control unit harness connector E142 terminal 11 (L)
L
and ground.
– Transfer control unit harness connector E142 terminal 12 (W/G)
and ground.
M
– Transfer control unit harness connector E142 terminal 21 (BR)
and ground.
Do indicator lamps turn on? SDIA2772E

OK >> GO TO 6.
NG >> Replace combination meter. Refer to IP-13, "Combination Meter" .

6. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 7.

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

7. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

4WD Warning Lamp Does Not Turn ON EDS002HN

SYMPTOM: A
4WD warning lamp does not turn ON when turning ignition switch to “ON”.
DIAGNOSTIC PROCEDURE
B
1. CHECK TRANSFER CONTROL UNIT POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.) C
2. Connect transfer control unit harness connector.
3. Check voltage between transfer control unit harness connector
terminals and ground. TF
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142 E
22 (Y/R) - Ground 0V
29 (L/W) - Ground
E143 30 (SB) - Ground F
Battery voltage
47 (W) - Ground
WDIA0165E

G
4. Turn ignition switch “ON”. (Do not start engine.)
5. Check voltage between transfer control unit harness connector
terminals and ground. H
Connector Terminal (Wire color) Voltage (Approx.)
16 (Y/R) - Ground
E142 I
22 (Y/R) - Ground Battery voltage
29 (L/W) - Ground
E143 30 (SB) - Ground 0V J
WDIA0166E
47 (W) - Ground Battery voltage

OK or NG
K
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
● 10A fuses No. 26 located in fuse and fusible link box and No. 59 located in the fuse and relay
box. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" . L
● 20A fuse No. 53 located in the IPDM E/R. Refer to PG-4, "POWER SUPPLY ROUTING CIR-
CUIT" .
● Harness for short or open between battery and transfer control unit harness connector termi-
M
nals 47.
● Harness for short or open between battery and transfer control unit harness connector terminal
29.
● Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 1 (G), and 3 (G).
● Harness for short or open between transfer shut off relay harness connector E69 terminal 2
(SB) and transfer control unit harness connector terminal 30.
● Harness for short or open between transfer shut off relay harness connector E69 terminal 5 (Y/
R) and transfer control unit harness connector terminals 16 (Y/R) and 22 (Y/R).
● Battery and ignition switch. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .

● Transfer shut off relay. Refer to TF-57, "COMPONENT INSPECTION" .

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

2. CHECK TRANSFER CONTROL UNIT GROUND CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminals 3 (B), 6 (B), E143 terminal 45 (B) and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.

SDIA2691E

3. CHECK COMBINATION METER POWER SUPPLY CIRCUIT

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check voltage between combination meter harness connector
terminal and ground.
Connector Terminal (Wire color) Voltage (Approx.)
M24 24 (O/L) - Ground 0V

WDIA0151E

4. Turn ignition switch “ON”. (Do not start engine.)

5. Check voltage between combination meter harness connector
terminal and ground.
Connector Terminal (Wire color) Voltage (Approx.)
M24 24 (O/L) - Ground Battery voltage
OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or
replace damaged parts. WDIA0152E

● 10A fuse No. 14 located in the fuse block (J/B). Refer

to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .
● Harness for short or open between battery and combination meter harness connector M24 ter-
minal 24 (O/L).
● Ignition switch. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

4. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND COMBINATION METER A

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and combination meter harness connector.
3. Check continuity between the following terminals. B
– Transfer control unit harness connector E142 terminal 5 (W/B)
and combination meter harness connector M24 terminal 34 (W/
B). C
Continuity should exist.
Also check harness for short to ground and short to power. TF
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts. E
WDIA0154E

5. CHECK INDICATOR LAMP CIRCUIT

F
1. Connect combination meter harness connector.
2. Disconnect transfer control unit harness connector.
3. Turn ignition switch “ON”. (Do not start engine.) G
4. Ground the following terminal using suitable wiring.
– Transfer control unit harness connector E142 terminal 5 (W/B)
and ground. H
Does 4WD warning lamp turn on?
OK >> GO TO 6.
NG >> Replace combination meter. Refer to IP-13, "Combina- I
tion Meter" .

J
SDIA2774E

6. SYMPTOM CHECK K
Check again.
OK or NG
L
OK >> Inspection End.
NG >> GO TO 7.

7. CHECK TRANSFER CONTROL UNIT M

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
4WD Shift Indicator Lamp or 4LO Indicator Lamp Does Not Change EDS002HO

SYMPTOM:
4WD shift indicator lamp or 4LO indicator lamp does not change when switching 4WD shift switch.

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

DIAGNOSTIC PROCEDURE
1. CONFIRM THE SYMPTOM
Confirm 4WD shift indicator lamp and 4LO indicator lamp turn on when ignition switch is turned to ON.
Do 4WD shift indicator lamp and 4LO indicator lamp turn on?
YES >> GO TO 2.
NO >> Go to TF-117, "4WD Shift Indicator Lamp and 4LO Indicator Lamp Do Not Turn ON" .

2. CHECK SYSTEM FOR 4WD SHIFT SWITCH

Perform trouble diagnosis for 4WD shift switch system. Refer to TF-62, "4WD Shift Switch" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. CHECK SYSTEM FOR WAIT DETECTION SWITCH

Perform trouble diagnosis for wait detection switch system. Refer to TF-66, "Wait Detection Switch" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.

4. CHECK SYSTEM FOR NEUTRAL-4LO SWITCH

Perform trouble diagnosis for neutral-4LO switch system. Refer to TF-59, "Neutral-4LO Switch" .
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.

5. CHECK SYSTEM FOR ATP SWITCH

Perform trouble diagnosis for ATP switch system. Refer to TF-113, "ATP Switch" .
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.

6. CHECK SYSTEM FOR 2-4WD SOLENOID

Perform trouble diagnosis for 2-4WD solenoid system. Refer to TF-91, "2-4WD Solenoid" .
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.

7. CHECK SYSTEM FOR TRANSFER CONTROL DEVICE

Perform trouble diagnosis for transfer control device system. Refer to TF-81, "Transfer Control Device" .
OK or NG
OK >> GO TO 8.
NG >> Repair or replace damaged parts.

8. CHECK SYSTEM FOR ACTUATOR MOTOR

Perform trouble diagnosis for actuator motor system. Refer to TF-70, "Actuator Motor" .
OK or NG
OK >> GO TO 9.
NG >> Repair or replace damaged parts.

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

9. CHECK SYSTEM FOR ACTUATOR POSITION SWITCH A

Perform trouble diagnosis for actuator position switch system. Refer to TF-77, "Actuator Position Switch" .
OK or NG
OK >> GO TO 10. B
NG >> Repair or replace damaged parts.

10. SYMPTOM CHECK C

Check again.
OK or NG
TF
OK >> Inspection End.
NG >> GO TO 11.

11. CHECK TRANSFER CONTROL UNIT E

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" . F
OK or NG
OK >> GO TO 12.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. G
If any items are damaged, repair or replace damaged parts.

12. CHECK TRANSFER INNER PARTS H

1. Disassemble transfer assembly. Refer to TF-144, "Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG I
OK >> Inspection End.
NG >> Repair or replace damaged parts.
J
ATP Warning Lamp Turns ON EDS002HP

SYMPTOM:
ATP warning lamp turns ON when 4WD shift switch from “4H” to “4LO” or “4LO” to “4H” with A/T K
selector lever “N” to “P” position.
DIAGNOSTIC PROCEDURE
1. CHECK SYSTEM FOR CAN COMMUNICATION LINE L

Perform self-diagnosis. Refer to TF-50, "Self-diagnostic Procedure" .

Do the self-diagnostic results indicate CAN communication? M
YES >> Perform trouble diagnosis for CAN communication line. Refer to TF-113, "CAN Communication
Line" .
NO >> GO TO 2.

2. CHECK SYSTEM FOR 4WD SHIFT SWITCH

Perform trouble diagnosis for 4WD shift switch system. Refer to TF-62, "4WD Shift Switch" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. CHECK SYSTEM FOR PNP SWITCH SIGNAL

Perform trouble diagnosis for PNP switch signal system. Refer to TF-69, "PNP Switch Signal (TCM)" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
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 TROUBLE DIAGNOSIS FOR SYMPTOMS

4. CHECK SYSTEM FOR ATP SWITCH

Perform trouble diagnosis for ATP switch system. Refer to TF-113, "ATP Switch" .
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.

5. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND COMBINATION METER

1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and combination meter harness connector.
3. Check continuity between the following terminals.
– Transfer control unit harness connector E142 terminal 15 (L/B)
and combination meter harness connector M24 terminal 6 (L/B).
Continuity should exist.

WDIA0149E

– Transfer control unit harness connector E143 terminal 40 (L)

and combination meter harness connector M24 terminal 7 (R/B).
40 to 7: Continuity should not exist.
7 to 40: Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.

WDIA0150E

6. CHECK ATP WARNING LAMP CIRCUIT

1. A/T selector lever in "P" position.
2. Connect combination meter harness connector and transfer control unit harness connector.
3. Disconnect ATP switch harness connector.
4. Ground the following terminal using suitable wiring.
– ATP switch harness connector F55 terminal 8 (L/Y) and ground.
5. Turn ignition switch “ON”. (Do not start engine.)
Does indicator lamp turn on?
OK >> GO TO 7.
NG >> Replace combination meter. Refer to IP-13, "Combina-
tion Meter" .

SDIA2769E

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

7. SYMPTOM CHECK A
Check again.
OK or NG
OK >> Inspection End. B
NG >> GO TO 8.

8. CHECK TRANSFER CONTROL UNIT C

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
TF
OK or NG
OK >> GO TO 9.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts. E

9. CHECK TRANSFER INNER PARTS

F
1. Disassemble transfer assembly. Refer to TF-144, "Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG G
OK >> Inspection End.
NG >> Repair or replace damaged parts.
4LO Indicator Lamp Repeats Flashing EDS002HQ
H
SYMPTOM:
4LO lamp keeps flashing.
I
DIAGNOSTIC PROCEDURE
1. CONFIRM THE SYMPTOM
J
1. Set 4WD shift switch to “2WD”.
2. Move vehicle forward and backward, or drive straight increasing or decreasing under 20 km/h (12 MPH).
Does 4WD shift indicator lamp keep flashing? K
YES >> GO TO 2.
NO >> Inspection End.
L
2. CHECK SYSTEM FOR WAIT DETECTION SWITCH
Perform trouble diagnosis for wait detection switch system. Refer to TF-66, "Wait Detection Switch" .
OK or NG M
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. CHECK SYSTEM FOR NEUTRAL-4LO SWITCH

Perform trouble diagnosis for neutral-4LO switch system. Refer to TF-59, "Neutral-4LO Switch" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.

4. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 5.

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 TROUBLE DIAGNOSIS FOR SYMPTOMS

5. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

6. CHECK TRANSFER INNER PARTS

1. Disassemble transfer assembly. Refer to TF-144, "Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG
OK >> Inspection End.
NG >> Repair or replace damaged parts.
4WD Warning Lamp Flashes Rapidly EDS002HR

SYMPTOM:
While driving, 4WD warning lamp flashes rapidly.
NOTE:
Rapid flashing: 2 times/second
DIAGNOSTIC PROCEDURE
1. CHECK TIRE
Check the following.
● Tire pressure
● Wear condition
● Longitudinal tire size (There is no difference between longitudinal tires.)
OK or NG
OK >> GO TO 2.
NG >> Repair or replace damaged parts.

2. CHECK 4WD WARNING LAMP

Stop the vehicle and allow it to idle for a short period of time.
Does flashing stop?
YES >> Inspection End.
NO >> GO TO 3.

3. CHECK TRANSFER FLUID TEMPERATURE

Perform trouble diagnosis for transfer fluid temperature system. Refer to TF-102, "Transfer Fluid Temperature"
.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.

4. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 5.

Revision: October 2005 TF-128 2005 QX56

 TROUBLE DIAGNOSIS FOR SYMPTOMS

5. CHECK TRANSFER CONTROL UNIT A

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG B
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts. C
4WD Warning Lamp Flashes Slowly EDS002HS

SYMPTOM:
While driving, 4WD warning lamp flashes slowly. (When continuing to flash until turning ignition TF
switch OFF.)
NOTE:
Slow flashing: 1 time/2 seconds E

DIAGNOSTIC PROCEDURE
1. CHECK TIRE F

Check the following.

● Tire pressure G
● Wear condition
● Longitudinal tire size (There is no difference between longitudinal tires.)
OK or NG H
OK >> GO TO 2.
NG >> Repair or replace damaged parts.
I
2. CHECK TRANSFER FLUID TEMPERATURE
Perform trouble diagnosis for transfer fluid temperature system. Refer to TF-102, "Transfer Fluid Temperature"
. J
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts. K

3. CHECK CLUTCH PRESSURE SWITCH

L
Perform trouble diagnosis for clutch pressure switch system. Refer to TF-105, "Clutch Pressure Switch" .
OK or NG
OK >> GO TO 4. M
NG >> Repair or replace damaged parts.

4. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 5.

5. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

Revision: October 2005 TF-129 2005 QX56

 TROUBLE DIAGNOSIS FOR SYMPTOMS

Heavy Tight-corner Braking Symptom Occurs EDS002HT

SYMPTOM:
Heavy tight-corner braking symptom occurs when vehicle is driven in AUTO mode and steering wheel
is turned fully to either side.
DIAGNOSTIC PROCEDURE
NOTE:
● Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not
a malfunction.
● Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is "4H" or "4LO", steering wheel is turned fully to either side.
1. CHECK SYSTEM FOR CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)" .
Is "CAN COMM CIRCUIT [U1000]" displayed?
YES >> Perform trouble diagnosis for CAN communication line. Refer to TF-113, "CAN Communication
Line" .
NO >> GO TO 2.

2. CHECK SYSTEM FOR 4WD SHIFT SWITCH

Perform trouble diagnosis for 4WD shift switch system. Refer to TF-62, "4WD Shift Switch" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. CHECK ACCELERATOR PEDAL POSITION SIGNAL CIRCUIT

Perform self diagnosis for ECM. Refer to EC-49, "Emission-related Diagnostic Information" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.

4. CHECK SYSTEM FOR CLUTCH PRESSURE SOLENOID

Perform trouble diagnosis for clutch pressure solenoid system. Refer to TF-105, "Clutch Pressure Switch" .
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.

5. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 6.

6. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 7.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.

Revision: October 2005 TF-130 2005 QX56

 TROUBLE DIAGNOSIS FOR SYMPTOMS

7. CHECK TRANSFER INNER PARTS A

1. Disassemble transfer assembly. Refer to TF-144, "Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG B
OK >> Inspection End.
NG >> Repair or replace damaged parts.
C
4WD System Does Not Operate EDS002HU

SYMPTOM:
The vehicle cannot be put into 4WD mode. (Hydraulic system failure) TF
DIAGNOSTIC PROCEDURE
1. CHECK SYSTEM FOR 4WD SHIFT SWITCH E
Perform trouble diagnosis for 4WD shift switch system. Refer to TF-62, "4WD Shift Switch" .
OK or NG
OK >> GO TO 2. F
NG >> Repair or replace damaged parts.

2. CHECK SYSTEM FOR CLUTCH PRESSURE SWITCH G

Perform trouble diagnosis for clutch pressure switch system. Refer to TF-105, "Clutch Pressure Switch" .
OK or NG H
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. SYMPTOM CHECK I

Check again.
OK or NG J
OK >> Inspection End.
NG >> GO TO 4.
K
4. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-36, "Transfer Control Unit Input/Output Signal Ref-
erence Values" . L
OK or NG
OK >> GO TO 5.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. M
If any items are damaged, repair or replace damaged parts.

5. CHECK TRANSFER INNER PARTS

1. Disassemble transfer assembly. Refer to TF-144, "Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG
OK >> Inspection End.
NG >> Repair or replace damaged parts.

Revision: October 2005 TF-131 2005 QX56

 TRANSFER CONTROL UNIT

TRANSFER CONTROL UNIT PFP:33084

Removal and Installation EDS002IS

REMOVAL
1. Set transfer state as 2WD when 4WD shift switch is at 2WD, or as AUTO when 4WD shift switch is at
AUTO.
CAUTION:
When removing transfer control unit, transfer state must be at 2WD or AUTO.
2. Turn the ignition switch OFF and disconnect negative battery terminal.
3. Remove the glove box assembly. Refer to IP-14, "Instrument Lower Cover RH and Glove Box" .
4. Disconnect the two transfer control unit connectors.
5. Remove the transfer control unit bolts.
6. Remove the transfer control unit.

BDIA0014E

INSTALLATION
Installation is in the reverse order of removal.
● When installing the transfer control unit, tighten bolts to the specified torque.
Transfer control unit bolts : 5.1 N·m (0.52 kg-m, 45 in-lb)
CAUTION:
● Do not connect harness connector to transfer control unit when 4WD shift switch is at 4LO.

● After the installation, check perform self-diagnosis. Refer to TF-50, "Self-diagnostic Procedure" . If NG,
adjust position between transfer assembly and transfer control unit. Refer to TF-4, "Precautions for Trans-
fer Assembly and Transfer Control Unit Replacement" .

Revision: October 2005 TF-132 2005 QX56

 FRONT OIL SEAL

FRONT OIL SEAL PFP:38189

A
Removal and Installation EDS002IT

REMOVAL
1. Partially drain the transfer fluid. Refer to MA-24, "DRAINING" .
B
2. Remove the front propeller shaft. Refer to PR-4, "Removal and Installation" .
3. Remove the companion flange self-lock nut, using Tool.
Tool number : KV40104000 ( — ) C

TF

SDIA2657E

4. Put a matching mark on top of the front drive shaft in line with F
the mark on the companion flange.
CAUTION:
Use paint to make the matching mark on the front drive G
shaft. Do not damage the front drive shaft.

SDIA2658E
I

5. Remove the companion flange, using suitable tool.

J

WDIA0193E

M
6. Remove the oil seal from the front case, using Tool.
Tool number : ST33290001 (J-34286)
CAUTION:
Do not damage front case.

LDIA0144E

Revision: October 2005 TF-133 2005 QX56

 FRONT OIL SEAL

INSTALLATION
1. Install the oil seal until it is flush with the end face of the front
case, using Tool.
Tool number : KV38100500 ( — )
CAUTION:
● Do not reuse oil seal.

● Apply petroleum jelly to oil seal.

SDIA2662E

2. Align the matching mark of the front drive shaft with the match-
ing mark of the companion flange, then install the companion
flange.

SDIA2658E

3. Install the self-lock nut. Tighten to the specified torque, using

Tool. Refer to TF-144, "COMPONENTS" .
Tool number : KV40104000 ( — )
CAUTION:
Do not reuse self-lock nut.
4. Install the front propeller shaft. Refer to PR-4, "Removal and
Installation" .
5. Refill the transfer with fluid and check fluid level. Refer to MA-
25, "FILLING" .
6. Check the transfer for fluid leakage. Refer to MA-25, "FLUID LDIA0147E

LEAKAGE AND FLUID LEVEL" .

Revision: October 2005 TF-134 2005 QX56

 REAR OIL SEAL

REAR OIL SEAL PFP:33140

A
Removal and Installation EDS002IU

REMOVAL
1. Partially drain the transfer fluid. Refer to MA-24, "DRAINING" .
B
2. Remove the rear propeller shaft. Refer to PR-8, "Removal and Installation" .
3. Remove the dust cover from the rear case.
CAUTION: C
Do not damage the rear case.

TF

WDIA0127E

F
4. Remove the rear oil seal from the rear case, using Tool.
CAUTION:
Do not damage the rear case.
G
Tool number : ST33290001 (J-34286)

I
LDIA0139E

INSTALLATION
1. Install the oil seal until it is flush with the end face of the rear J
case, using Tool.
Tool number : ST30720000 (J-25405)
CAUTION: K
● Do not reuse oil seal.

● Apply petroleum jelly to oil seal.

L

LDIA0140E M

2. Apply petroleum jelly to the circumference of the new dust cover.

Position the dust cover using the identification mark as shown.
CAUTION:
● Do not reuse dust cover.

● Position the identification mark at the position shown.

SDIA2208E

Revision: October 2005 TF-135 2005 QX56

 REAR OIL SEAL

3. Install the dust cover to the rear case, using Tool.

Tool number : KV40105310 ( — )
CAUTION:
● Do not reuse dust cover.

● Apply petroleum jelly to dust cover.

4. Install the rear propeller shaft. Refer to PR-8, "Removal and

Installation" .
5. Refill the transfer with fluid and check fluid level. Refer to MA-
25, "FILLING" .
PDIA0116E
6. Check the transfer for fluid leakage. Refer to MA-25, "FLUID
LEAKAGE AND FLUID LEVEL" .

Revision: October 2005 TF-136 2005 QX56

 SIDE OIL SEAL

SIDE OIL SEAL PFP:33142

A
Removal and Installation EDS002IV

REMOVAL
1. Remove the front propeller shaft. Refer to PR-4, "Removal and Installation" .
B
2. Remove the companion flange. Refer to TF-133, "Removal and Installation" .
3. Remove the transfer control device from the transfer assembly. Refer to TF-138, "Removal and Installa-
tion" .
C
4. Remove the side oil seal.
CAUTION:
Do not damage shift cross. TF

F
SDIA2666E

INSTALLATION
1. Install the side oil seal until it is flush with the end face of case, G
using Tool.
Tool number : ST22360002 (J-25679-01)
H
CAUTION:
● Do not reuse oil seal.

● Apply petroleum jelly to oil seal.

I
2. Install the transfer control device to the transfer assembly. Refer
to TF-138, "Removal and Installation" .
3. Install the companion flange. Refer to TF-133, "Removal and J
Installation" . SDIA2665E

4. Install the front propeller shaft. Refer to PR-4, "Removal and Installation" .
K

Revision: October 2005 TF-137 2005 QX56

 TRANSFER CONTROL DEVICE

TRANSFER CONTROL DEVICE PFP:33251

Removal and Installation EDS002IW

Refer to the figure for transfer control device removal and installation information.
CAUTION:
● Change vehicle state to 2WD or AUTO, and then remove and install transfer control device.
● Check 4WD shift indicator after installation. Refer to TF-4, "Precautions for Transfer Assembly and
Transfer Control Unit Replacement" .

SDIA2654E

1. Shift lever 2. Actuator

Revision: October 2005 TF-138 2005 QX56

 AIR BREATHER HOSE

AIR BREATHER HOSE PFP:31098

A
Removal and Installation EDS002IX

Refer to the figure for air breather hose removal and installation information.
B

TF

SDIA2656E J
CAUTION:
● Make sure there are no pinched or restricted areas on the air breather hose caused by bending or
winding when installing it. K
● Install the air breather hose into the air breather (metal connector) and actuator (case connector)
until the hose end reaches the base of the tube.
● Install the air breather hose into the breather tube (metal connector) and transfer motor (case con- L
nector) until the hose end reaches the end of the curved section.

Revision: October 2005 TF-139 2005 QX56

 TRANSFER MOTOR

TRANSFER MOTOR PFP:00000

Removal and Installation EDS002IY

REMOVAL
1. Disconnect the transfer motor connector.
2. Remove the air breather hose from the transfer motor. Refer to
TF-139, "Removal and Installation" .
3. Remove the transfer motor bolts.
4. Remove the transfer motor.

SDIA2133E

INSTALLATION
1. Apply ATF to the O-ring and install it to the transfer motor.
CAUTION:
Do not reuse O-rings.
2. Fit the double-flat end of the transfer motor shaft into the slot of
the sub-oil pump assembly. Then tighten to the specified torque.
Refer to TF-144, "COMPONENTS" .
CAUTION:
Be sure to install connector bracket.
3. Install the air breather hose to the transfer motor. Refer to TF-
139, "Removal and Installation" . SDIA2787E
4. Connect the transfer motor connector.
5. Check the transfer fluid. Refer to MA-25, "FLUID LEAKAGE AND FLUID LEVEL" .
6. Start the engine for one minute. Then stop the engine and recheck the transfer fluid. Refer to MA-25,
"FLUID LEAKAGE AND FLUID LEVEL" .

Revision: October 2005 TF-140 2005 QX56

 TRANSFER OIL FILTER

TRANSFER OIL FILTER PFP:00000

A
Removal and Installation EDS002IZ

REMOVAL
1. Remove the oil filter bolts and oil filter.
B
CAUTION:
● Do not damage center case and oil filter.

● Loosen bolts and detach oil filter evenly.

C

TF

SMT875C
E
2. Remove the O-rings from the oil filter.

H
SDIA2327E

3. Remove the oil filter stud from the oil filter. I

4. Remove the O-ring from the oil filter stud.

SDIA2784E
L

INSTALLATION
1. Apply ATF to the O-ring, and install it on the oil filter stud.
M
CAUTION:
Do not reuse O-ring.
2. Install the oil filter stud to the oil filter.

SDIA2784E

Revision: October 2005 TF-141 2005 QX56

 TRANSFER OIL FILTER

3. Apply ATF to the two O-rings (1), and install them on the oil filter
(2).
CAUTION:
Do not reuse O-rings.

WDIA0285E

4. Install the oil filter to the transfer assembly. Tighten the bolts to
the specified torque. Refer to TF-144, "COMPONENTS" .
CAUTION:
● Do not damage oil filter.

● Attach oil filter and tighten bolts evenly.

5. Check the transfer fluid. Refer to MA-25, "FLUID LEAKAGE

AND FLUID LEVEL" .
6. Start the engine for one minute. Then stop the engine and
recheck the transfer fluid. Refer to MA-25, "FLUID LEAKAGE
AND FLUID LEVEL" . SDIA2136E

Revision: October 2005 TF-142 2005 QX56

 TRANSFER ASSEMBLY

TRANSFER ASSEMBLY PFP:33100

A
Removal and Installation EDS002H1

REMOVAL
1. Remove the drain plug and gasket. Drain the fluid. Refer to MA-24, "DRAINING" .
B
2. Remove the A/T undercover, using power tool.
3. Remove the center exhaust tube and main muffler. Refer to EX-3, "Removal and Installation" .
4. Remove the front and rear propeller shafts. Refer to PR-4, "Removal and Installation" (front), PR-8, C
"Removal and Installation" (rear).
CAUTION:
Do not damage spline, sleeve yoke and rear oil seal when removing rear propeller shaft. TF
NOTE:
Insert a plug into the rear oil seal after removing the rear propeller shaft.
5. Remove the A/T nuts from the A/T crossmember. E
6. Position two suitable jacks under the A/T and transfer assembly.
7. Remove the crossmember. Refer to AT-247, "COMPONENTS" .
WARNING: F
Support A/T and transfer assembly using two suitable jacks while removing crossmember.
8. Disconnect the electrical connectors from the following:
● ATP switch G
● Neutral 4LO switch

● Wait detection switch

H
● Transfer motor

● Transfer control device

9. Disconnect the air breather hoses from the following:

I
● Transfer control device

● Transfer rear case

● Transfer motor J
10. Remove the transfer control device from the extension housing.
11. Remove the transfer to A/T and A/T to transfer bolts.
WARNING: K
Support transfer assembly with suitable jack while removing it.
12. Remove the transfer assembly.
L
INSTALLATION
Installation is in the reverse order of removal, paying attention to the following:
● Tighten the bolts to specification. M
Bolt length : 45 mm (1.77 in)
Transfer bolt torque : 36 N·m (3.7 kg-m, 26 ft-lb)
● Fill the transfer with new fluid. Refer to MA-25, "FILLING" .
● Check the transfer fluid. Refer to MA-25, "FLUID LEAKAGE
AND FLUID LEVEL" .
● Start the engine for one minute. Then stop the engine and
recheck the transfer fluid. Refer to MA-25, "FLUID LEAKAGE
AND FLUID LEVEL" . SMT872C

Revision: October 2005 TF-143 2005 QX56

 TRANSFER ASSEMBLY

Disassembly and Assembly EDS002H2

COMPONENTS

WDIA0194E

1. 2-4 sleeve 2. L-H sleeve 3. Snap ring

4. Internal gear 5. Planetary carrier assembly 6. Metal bushing
7. Needle bearing 8. Sun gear 9. Carrier bearing
10. Snap ring 11. Snap ring 12. Mainshaft front bearing
13. Wait detection switch 14. Check plug 15. Check spring
16. Check ball 17. Front case 18. Snap ring
19. Oil seal 20. Shift cross 21. Oil seal
22. Lock pin 23. Shift lever 24. Gasket
25. Drain plug 26. Oil seal 27. Companion flange
28. Self-lock nut 29. Main shaft 30. Needle bearing
31. Front bearing 32. Front drive shaft 33. Rear bearing
34. Spacer 35. Drive chain 36. Clutch drum
37. Snap ring 38. Clutch hub 39. Snap ring
40. Retaining plate 41. Driven plate (10 sheet) 42. Drive plate (10 sheet)
43. Return spring assembly 44. Press flange 45. Thrust needle bearing
46. Snap ring 47. Retaining pin 48. L-H fork

Revision: October 2005 TF-144 2005 QX56

 TRANSFER ASSEMBLY

49. 2-4 fork 50. Shift fork spring 51. Fork guide
52. Retainer pin 53. Shift rod A

TF

WDIA0195E
M
1. Dust cover 2. Oil seal 3. Rear case
4. Air breather 5. Seal ring 6. Main oil pump cover
7. Inner gear 8. Outer gear 9. Main oil pump housing
10. D-ring 11. D-ring 12. Clutch piston
13. Thrust needle bearing race 14. Oil strainer 15. O-ring
16. Snap ring 17. Control valve assembly 18. Lip seal (7 pieces)
19. Gasket 20. Filler plug 21. Oil filter stud
22. O-ring 23. Oil filter 24. ATP switch
25 Neutral-4LO switch 26. Oil pressure check plug 27. Harness bracket
28. Stem bleeder 29. Harness bracket 30. Center case
31. Mainshaft rear bearing 32. C-ring 33. Washer holder
34. Snap ring 35. Sub oil pump housing 36. Outer gear
37. Inner gear 38. Sub oil pump cover 39. O-ring
40. Transfer motor 41. Connector bracket

Revision: October 2005 TF-145 2005 QX56

 TRANSFER ASSEMBLY

DISASSEMBLY
Rear Case
1. Remove the rear case bolts.

SDIA2092E

2. Remove the rear case from the center case.

SDIA2093E

3. Remove the dust cover, using suitable tool.

SDIA2094E

4. Remove the oil seal, using suitable tool.

CAUTION:
Do not damage rear case.
5. Remove the air breather.

SDIA2095E

Revision: October 2005 TF-146 2005 QX56

 TRANSFER ASSEMBLY

Front Case
1. Remove the rear case assembly. Refer to TF-146, "Rear Case" . A
2. Remove the transfer control device. Refer to TF-138, "Removal and Installation" .
3. Remove the lock pin nut.
B
4. Remove the lock pin, using suitable tool.
5. Remove the shift lever.
C

TF

SDIA2150E
E
6. Remove the oil seal from the front case, using suitable tool.
CAUTION:
Do not damage front case or shift cross. F

H
SDIA2166E

7. Remove the check plug, check spring and check ball. I

8. Remove the wait detection switch.

WDIA0196E L

9. Remove the self-lock nut from the companion flange, using Tool.
Tool number : KV40104000 ( — ) M

SDIA2657E

Revision: October 2005 TF-147 2005 QX56

 TRANSFER ASSEMBLY

10. Put a matching mark on top of the front drive shaft thread in line
with the mark on the companion flange.
CAUTION:
Use paint to make the matching mark on the front drive
shaft thread. Never damage the front drive shaft.

SDIA2779E

11. Remove the companion flange, using suitable tool.

WDIA0133E

12. Remove the center case bolts and harness bracket.

13. Remove the filler plug and gasket.

SDIA2100E

14. Separate the center case from the front case. Then remove the
center case from the front case by prying it up, using suitable
tool.
CAUTION:
Do not damage the mating surfaces.

SDIA2101E

15. Remove the shift rod components together with the 2-4 sleeve
and L-H sleeve.
16. Remove the shift cross from the front case.

SDIA2140E

Revision: October 2005 TF-148 2005 QX56

 TRANSFER ASSEMBLY

17. Remove the 2-4 sleeve and L-H sleeve from the 2-4 fork and L-
H fork respectively. A

SMT992C
TF
18. Drive out the retaining pin from the shift rod, using suitable tool.

G
WDIA0134E

19. Remove the L-H fork, 2-4 fork, shift fork spring and fork guide H
from the shift rod.

SDIA2142E K

20. Remove the oil seal from the front case, using suitable tool.
CAUTION: L
Do not damage front case or sun gear.

SDIA2143E

21. Remove the snap ring from the sun gear.

CAUTION:
Do not damage front case or sun gear.

SDIA2144E

Revision: October 2005 TF-149 2005 QX56

 TRANSFER ASSEMBLY

22. Remove the sun gear assembly and planetary carrier assembly
from the front case, using Tool.
Tool number : ST35300000 ( — )

SDIA2145E

23. Remove the snap ring and internal gear, using suitable tool.

SMT004D

24. Remove the oil seal, using suitable tool.

CAUTION:
Do not damage front case.

SDIA2170E

25. Remove the snap ring from the front case.

SDIA2171E

26. Remove the mainshaft front bearing from the front case, using
Tool.
Tool number : ST33200000 (J-26082)

SDIA2178E

Revision: October 2005 TF-150 2005 QX56

 TRANSFER ASSEMBLY

27. Remove the snap ring from the planetary carrier assembly,
using suitable tool. A

SDIA2146E

TF
28. Remove the sun gear assembly from the planetary carrier
assembly.
E

G
SDIA2147E

29. Remove the snap ring from the sun gear, using suitable tool.
H

SDIA2148E
K
30. Remove the carrier bearing from the sun gear, using Tools.
Tool number A: ST35300000 ( — ) L
B: ST30031000 ( — )

SDIA2149E

31. Remove the needle bearing from the sun gear, using Tool.
Tool number : ST33710000 ( — )

SDIA2354E

Revision: October 2005 TF-151 2005 QX56

 TRANSFER ASSEMBLY

32. Remove the metal bushing from the sun gear, using Tools.
Tool number A: ST33710000 ( — )
B: ST35325000 ( — )
C: ST33290001 (J-34286)

SDIA2168E

Center Case
1. Remove the rear case assembly. Refer to TF-146, "Rear Case" .
2. Remove the front case assembly. Refer to TF-147, "Front Case" .
3. Hold the front drive shaft with one hand and tap to remove the
front drive shaft with the drive chain.
CAUTION:
Do not tap drive chain.

SMT900C

4. Remove the front drive shaft front bearing, using Tools.

Tool number A: ST33052000 ( — )
B: ST30031000 ( — )

SDIA2106E

5. Remove the front drive shaft rear bearing, using Tools.

Tool number A: ST33052000 ( — )
B: ST30031000 ( — )

SDIA2107E

Revision: October 2005 TF-152 2005 QX56

 TRANSFER ASSEMBLY

6. Remove the neutral-4LO and ATP switches.

A

SDIA2096E

TF
7. Remove the bolts and main oil pump.

G
SDIA2130E

8. Remove the outer gear and inner gear from the main oil pump
H
housing.

SDIA2131E
K
9. Remove the seal ring from the main oil pump cover.

SDIA2783E

10. Remove the stem bleeder from the bleed hole.

SDIA2780E

Revision: October 2005 TF-153 2005 QX56

 TRANSFER ASSEMBLY

11. Remove the snap ring and washer holder from the mainshaft.

SDIA2104E

12. Remove the C-rings from the mainshaft, using suitable tool.

SDIA2105E

13. Set the center case on the press stand. Remove the mainshaft
from the center case.

SDIA2108E

14. Remove the snap ring from the mainshaft, using suitable tool.

SDIA2110E

15. Remove the thrust needle bearing from the press flange.

SDIA2109E

Revision: October 2005 TF-154 2005 QX56

 TRANSFER ASSEMBLY

16. Press the flange until the snap ring is out of place, using Tools.
A
Tool number A: ST22452000 (J-34335)
B: ST30911000 ( — )
C: KV31103300 ( — ) B

SDIA2111E
TF
17. Remove the snap ring from the mainshaft, using suitable tool.

G
SDIA2112E

18. Remove the press flange from the mainshaft.

H

SMT910C
K
19. Remove the return spring assembly from the clutch hub.

SMT911C

20. Remove each plate from the clutch drum.

SMT912C

Revision: October 2005 TF-155 2005 QX56

 TRANSFER ASSEMBLY

21. Remove the snap ring from the mainshaft.

SDIA2113E

22. Remove the mainshaft from the clutch drum and clutch hub,
using suitable tool.
23. Remove the needle bearing and spacer from the mainshaft.

SMT914C

24. Remove the snap ring from the clutch hub, using suitable tool.

WDIA0101E

25. Remove the oil pressure check plug from the oil pressure check
port.

WDIA0227E

26. Apply air gradually from the oil pressure check port, and remove
the clutch piston assembly from the center case.

SDIA2116E

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 TRANSFER ASSEMBLY

27. Remove the thrust needle bearing race from the clutch piston by
hooking a edge into 3 notches of the thrust needle bearing race, A
using suitable tool.
CAUTION:
Do not damage clutch piston or thrust needle bearing race. B

SDIA2118E
TF
28. Remove the two D-rings from the clutch piston.

G
SDIA2781E

29. Remove the mainshaft rear bearing from the center case, using H
Tool.
Tool number : KV38100300 (J-25523)
I

SDIA2129E K
30. Remove the two bolts and oil strainer.

SDIA2119E

31. Remove the two O-rings from the oil strainer.

SDIA2782E

Revision: October 2005 TF-157 2005 QX56

 TRANSFER ASSEMBLY

32. Remove the snap ring. Then push the connector assembly into
the center case to remove the control valve assembly.

SDIA2122E

33. Remove the control valve assembly bolts.

34. Remove the control valve assembly.
CAUTION:
● Do not reuse any part that has been dropped or damaged.

● Make sure valve is assembled in the proper direction.

● Do not use a magnet because residual magnetism stays

during disassembly.

SDIA2121E

35. Remove the lip seals from the center case.

CAUTION:
There are two kinds of lip seals (lip seal of large inner diam-
eter: 5 pieces, lip seal of small inner diameter: 2 pieces).
Confirm the position before disassembly.

SDIA2123E

36. Disassemble the control valve assembly with the following procedure.
CAUTION:
● Do not reuse any part that has been dropped or damaged.

● Make sure valve is assembled in the proper direction.

● Do not use a magnet because residual magnetism stays during disassembly.

a. Remove all the bolts except for the two shown.

WDIA0198E

Revision: October 2005 TF-158 2005 QX56

 TRANSFER ASSEMBLY

b. Remove the following from the control valve assembly:

● Clutch pressure solenoid valve A
● Clutch pressure switch

● 2-4WD shift solenoid valve

B
● Line pressure switch

● Transfer fluid temperature sensor

c. Remove the O-rings from each solenoid valve, switch and termi- C
nal body.

WDIA0199E

TF
d. Place the control valve with the lower body facing up. Remove
the two bolts, and then remove the lower body and separator
plate from the upper body.
E
CAUTION:
Do not drop relief balls. Detach lower body carefully.
F

G
SDIA2125E

e. Make sure the reverse balls, relief balls, relief springs, accumu-
H
lator pistons and valve springs are securely installed as shown,
and remove them.

SDIA2126E
K
f. Remove the retainer plates.

SDIA2127E

g. Remove each plug (2), control valve (3) and spring (4) from the
upper body (5).
● Retainer plate (1)

WDIA0284E

Revision: October 2005 TF-159 2005 QX56

 TRANSFER ASSEMBLY

37. Remove the transfer motor bolts and motor from the center
case. Then remove the O-ring from the transfer motor.

SDIA2133E

38. Remove the sub oil pump cover bolts.

SDIA2134E

39. Thread two bolts (M4 x 0.8) into the holes of sub oil pump cover
as shown, and pull out to remove the sub oil pump assembly.

SMT934C

40. Remove the outer gear and inner gear from the sub oil pump
housing.

SDIA2135E

41. Remove the oil filter bolts and oil filter.

CAUTION:
● Do not damage center case and oil filter.

● Loosen bolts and detach oil filter evenly.

SDIA2136E

Revision: October 2005 TF-160 2005 QX56

 TRANSFER ASSEMBLY

42. Remove the O-rings from the oil filter.

A

SDIA2327E
TF
43. Remove the oil filter stud from the oil filter.
44. Remove the O-ring from the oil filter stud.
E

G
SDIA2784E

INSPECTION AFTER DISASSEMBLY

H
Shift Rod Components
● Check the working face of the shift rod and fork for wear, partial
wear, bending and other abnormality. If any is found, replace
I
with a new one.

SMT009D

L
● Measure the clearance between the shift fork and sleeve. If it is
out of specification, replace it with a new one.
Specification : Less than 0.36 mm (0.0142 in) M

SMT010D

Revision: October 2005 TF-161 2005 QX56

 TRANSFER ASSEMBLY

Planetary Carrier
● Measure the end play of each pinion gear. If it is out of specifica-
tion, replace the planetary carrier assembly with a new one.
Pinion gear end play : 0.1 - 0.7 mm (0.004 - 0.028 in)
● Check the working face of each gear and bearing for damage,
burrs, partial wear, dents and other abnormality. If any is found,
replace the planetary carrier assembly with a new one.

PDIA0185E

Sun Gear
● Check if the oil passage of the sun gear assembly is clogged.
For this, try to pass a 3.6 mm (0.142 in) dia. pin through the oil
passage as shown.
● Check the sliding and contact surface of each gear and bearing
for damage, burrs, partial wear, dents, and other abnormality. If
any is found, replace the sun gear assembly with a new one.

PDIA0186E

Internal Gear
● Check the internal gear teeth for damage, partial wear, dents
and other abnormality. If any is found, replace the internal gear
with a new one.

SMT008D

Gears and Drive Chain

● Check the gear faces and shaft for wear, cracks, damage, and
seizure.
● Check the surfaces which contact the sun gear, clutch drum,
clutch hub, press flange, clutch piston and each bearing for
damage, peel, partial wear, dents, bending, or other abnormal
damage. If any is found, replace with a new one.

SMT944C

Revision: October 2005 TF-162 2005 QX56

 TRANSFER ASSEMBLY

Bearing
● Make sure the bearings roll freely and are free from noise, pit- A
ting and cracks.

SDIA2175E
TF

Main Oil Pump

1. Check the inner and outer circumference, tooth face, and side- E
face of the inner and outer gears for damage or abnormal wear.
2. Measure the side clearance between the main oil pump housing
edge and the inner and outer gears.
F
3. Make sure the side clearance is within specification. If the mea-
surement is out of specification, replace the inner and outer
gears with new ones as a set. Refer to TF-163, "Main Oil Pump"
. G

Specification : 0.015 - 0.035 mm (0.0006 - 0.0014 in)

SDIA2174E
H
Sub-oil Pump
1. Check the inner and outer circumference, tooth face, and side-
face of the inner and outer gears for damage or abnormal wear. I
2. Measure the side clearance between the sub oil pump housing
edge and the inner and outer gears.
3. Make sure the side clearance is within specification. If the mea- J
surement is out of specification, replace the inner and outer
gears with new ones as a set. Refer to TF-163, "Sub-oil Pump" .
Specification : 0.015 - 0.035 mm (0.0006 - 0.0014 in) K

SDIA2173E

L
Control Valve
● Check resistance between the terminals of the clutch pressure
solenoid valve, 2-4WD shift solenoid valve, clutch pressure
switch and the transfer fluid temperature sensor. Refer to TF-90, M
"COMPONENT INSPECTION" (clutch pressure solenoid
valve), TF-94, "COMPONENT INSPECTION" (2-4WD solenoid
valve), TF-107, "COMPONENT INSPECTION" (clutch pressure
switch) and TF-104, "COMPONENT INSPECTION" (transfer
fluid temperature sensor).

WDIA0199E

Revision: October 2005 TF-163 2005 QX56

 TRANSFER ASSEMBLY

● Check the sliding faces of the control valves and plugs for
abnormality. If any is found, replace the control valve assembly
with a new one. Refer to TF-182, "Control Valve" .
CAUTION:
Replace control valve body together with clutch return
spring as a set.

SMT947C

● Check each control valve spring for damage or distortion. Also

check its free length, outer diameter and wire diameter. If any
damage or fatigue is found, replace the control valve body with a
new one. Refer to TF-182, "Control Valve Spring" .
CAUTION:
Replace control valve body together with clutch return
spring as a set.

SMT948C

Clutch
● Check the drive plate facings and driven plate for damage,
cracks or other abnormality. If any abnormalities are found,
replace with a new one.
● Check the thickness of the drive plate facings and driven plate.
Refer to TF-164, "Clutch" .
CAUTION:
● Measure facing thickness at 3 points to take an average.

● Check all drive and driven plates.

● Check return spring for damage or deformation.

● Do not remove spring from plate. SMT949C

Return Spring
● Check the stamped mark shown. Then, check that the free
lengths, (include thickness of plate) are within specifications. If
any abnormality is found, replace with a new return spring
assembly of the same stamped number. Refer to TF-164,
"Return Spring" .

SDIA2176E

Revision: October 2005 TF-164 2005 QX56

 TRANSFER ASSEMBLY

ASSEMBLY
Center Case A
1. Apply ATF to the O-ring, and install it on the oil filter stud.
CAUTION:
Do not reuse O-rings. B
2. Install the oil filter stud to the oil filter.

TF
SDIA2784E

3. Apply ATF to the two O-rings (1), and install them on the oil filter E
(2).
CAUTION:
Do not reuse O-rings. F

WDIA0285E H

4. Install the oil filter to the center case. Tighten the bolts to the
specified torque. Refer to TF-144, "COMPONENTS" .
I
CAUTION:
● Do not damage oil filter.

● Attach oil filter and tighten bolts evenly.

J

SDIA2136E

L
5. Install the outer gear and inner gear into the sub oil pump hous-
ing, and measure the side clearance. Refer to TF-163, "Sub-oil
Pump" .
M

SDIA2135E

Revision: October 2005 TF-165 2005 QX56

 TRANSFER ASSEMBLY

6. Align the dowel pin hole and bolt hole of the sub oil pump
assembly with the center case. Install the sub oil pump cover.
Then tighten to the specified torque. Refer to TF-144, "COMPO-
NENTS" .

SDIA2328E

7. Apply ATF to the O-ring and install it to the transfer motor.

CAUTION:
Do not reuse O-rings.
8. Fit the double-flat end of the transfer motor shaft into the slot of
the sub-oil pump assembly. Then tighten to the specified torque.
Refer to TF-144, "COMPONENTS" .
CAUTION:
Be sure to install connector bracket.

SDIA2787E

9. Assemble the control valve assembly with the following procedure.

CAUTION:
● Do not reuse any part that has been dropped or damaged.

● Make sure valve is assembled in the proper direction.

● Do not use a magnet because residual magnetism stays during assembly.

● Retainer plate (1)

● Plug (2)

a. Clean the upper body (5), control valves (3) and springs (4) with
cleaning agent, and dry with compressed air.
b. Dip the control valves (3) in ATF, and apply ATF to the valve-
mounting area of the upper body (5).

WDIA0284E

c. Install each control valve, spring, and plug to the upper body,
and install retainer plates to hold them in place.
CAUTION:
● To insert control valves into upper body, place upper
body on a level surface in order to prevent flaw or dam-
age.
● Make sure each control valve is smoothly inserted.

SDIA2127E

Revision: October 2005 TF-166 2005 QX56

 TRANSFER ASSEMBLY

d. Install the reverse balls, relief balls and relief springs, accumula-
tor pistons and valve springs to the upper body. A

SDIA2126E

TF
e. Install the lower body and separator plate to the upper body.
CAUTION:
Do not reuse separator plates. E

G
WDIA0200E

f. With the lower body down, tighten the two bolts shown.
H
g. Apply ATF to the O-rings, and install them to each solenoid
valve, switch and terminal body.
CAUTION: I
Do not reuse O-rings.
h. Install the following to the control valve assembly:
● Clutch pressure solenoid valve
J
● Clutch pressure switch

● 2-4WD shift solenoid valve

WDIA0198E
● Line pressure switch K
● Transfer fluid temperature sensor

10. Apply ATF to lip seals, and install them to the center case. L
CAUTION:
● Do not reuse lip seals.

● There are 2 kinds of lip seals (lip seal of large inner diam- M
eter: 5 pieces, lip seal of small inner diameter: 2 pieces).
Confirm their position for installation.

SDIA2123E

Revision: October 2005 TF-167 2005 QX56

 TRANSFER ASSEMBLY

11. Install the control valve assembly to the center case, and tighten
to the specified torque. Refer to TF-144, "COMPONENTS" .
CAUTION:
● Do not reuse any part that has been dropped or damaged.

● Make sure valve is assembled in the proper direction.

● Do not use a magnet because residual magnetism stays

during assembly.

SDIA2121E

12. Install the connector assembly into the center case, and secure
with a snap ring.

SDIA2122E

13. Apply ATF to the O-rings, and install them on the oil strainer.
CAUTION:
Do not reuse O-rings.
14. Install the oil strainer to the control valve assembly.

SDIA2782E

15. Tighten the bolts to the specified torque. Refer to TF-144,

"COMPONENTS" .

SDIA2119E

16. Apply ATF to the D-rings, and install them to the clutch piston.
CAUTION:
Do not reuse D-rings.

SDIA2781E

Revision: October 2005 TF-168 2005 QX56

 TRANSFER ASSEMBLY

17. Install the thrust needle bearing race to the clutch piston.
A

SDIA2189E
TF
18. Install the clutch piston to the center case as shown.
CAUTION:
Install so the fitting protrusion of clutch piston aligns with E
the dent of center case.

G
SDIA2190E

19. Remove all the sealant from the oil pressure check port and H
inside the center case.
CAUTION:
Remove old sealant adhering to mounting surfaces. Also I
remove any moisture, oil, or foreign material adhering to
application and mounting surfaces.
20. Thread the oil pressure check plug in 1 or 2 pitches and apply
sealant to the oil pressure check plug threads. Tighten to the J
specified torque. Refer to TF-144, "COMPONENTS" .
● Use Genuine Silicone RTV or equivalent. Refer to GI-45,
"Recommended Chemical Products and Sealants" . SMT915C K
CAUTION:
Do not reuse oil pressure check plug.
21. Install the snap ring to the clutch hub, using suitable tool. L
CAUTION:
Do not reuse snap ring.
M

WDIA0101E

Revision: October 2005 TF-169 2005 QX56

 TRANSFER ASSEMBLY

22. Apply petroleum jelly to the needle bearing, and install the nee-
dle bearing, spacer, clutch drum and clutch hub to the main-
shaft.

WDIA0129E

23. Install the snap ring to the mainshaft.

CAUTION:
Do not reuse snap rings.

SDIA2192E

24. Apply ATF each plate, then install them into the clutch drum as
shown.

SDIA2193E

25. Install the return spring assembly into the clutch hub.

SMT911C

26. Install the press flange by aligning the notches to the clutch hub
as shown.

SDIA2194E

Revision: October 2005 TF-170 2005 QX56

 TRANSFER ASSEMBLY

27. Press the press flange to install snap ring into snap ring groove
on mainshaft, using Tools. A
Tool number A: ST22452000 (J-34335)
B: ST30911000 ( — )
B
C: KV31103300 ( — )
CAUTION:
Do not reuse snap ring. C

SDIA2111E
TF
28. Install the snap ring to the mainshaft, using suitable tool.
CAUTION:
Do not reuse snap ring. E

G
SDIA2112E

29. Apply ATF to the thrust needle bearing and install it on the press H
flange.

SDIA2109E K

30. Install the snap ring to the main shaft.

CAUTION: L
Do not reuse snap ring.

SDIA2195E

31. Install the mainshaft rear bearing to the center case, using Tool.
Tool number : ST15310000 (J-25640-B)

SDIA2196E

Revision: October 2005 TF-171 2005 QX56

 TRANSFER ASSEMBLY

32. Install the mainshaft assembly, using a press.

● Press the mainshaft into the center case, using Tools.

Tool number A: ST30911000 ( — )

B: ST33052000 ( — )

SDIA2197E

33. Install the C-rings to the mainshaft.

SDIA2201E

34. Set the washer holder on the mainshaft, and secure it with a
snap ring.
CAUTION:
Do not reuse snap ring.

SDIA2104E

35. Apply petroleum jelly to the stem bleeder and install it to the cen-
ter case.

SDIA2780E

36. Apply ATF to the seal ring and install it to the main oil pump
cover.
CAUTION:
Do not reuse seal ring.

SDIA2783E

Revision: October 2005 TF-172 2005 QX56

 TRANSFER ASSEMBLY

37. Install the inner gear and outer gear in the main oil pump hous-
ing. Then, measure the side clearance. Refer to TF-163, "Main A
Oil Pump" .

SDIA2174E
TF
38. Install the main oil pump housing, outer gear and inner gear to
the center case.
E

G
SDIA2188E

39. Install the main oil pump cover to the center case, and tighten to H
the specified torque. Refer to TF-144, "COMPONENTS" .

SDIA2130E K

40. Remove all the sealant from the switch mounting area and
inside the center case.
L
CAUTION:
Remove old sealant adhering to mounting surfaces. Also
remove any moisture, oil, or foreign material adhering to
application and mounting surfaces. M
41. Thread the ATP switch and neutral-4LO switch in one to two
pitches and apply sealant to the threads of the switches. Tighten
to the specified torque. Refer to TF-144, "COMPONENTS" .
● Use Genuine Silicone RTV or equivalent. Refer to GI-45,
"Recommended Chemical Products and Sealants" . SDIA2096E

NOTE:
● Neutral-4LO switch harness connector is gray.

● ATP switch harness connector is black.

Revision: October 2005 TF-173 2005 QX56

 TRANSFER ASSEMBLY

42. Install the front drive shaft rear bearing, using Tools.
Tool number A: KV40100621 (J-25273)
B: ST30032000 (J-26010-01)

SDIA2198E

43. Install the front drive shaft to the front bearing, using Tools.
Tool number A: KV40100621 (J-25273)
B: ST30032000 (J-26010-01)

SDIA2199E

44. Install the drive chain to the front drive shaft and clutch drum.
CAUTION:
Install drive chain by aligning identification marks to the
rear as shown.

SDIA2200E

45. Tap the front drive shaft while keeping it upright and press-fit the
front drive shaft rear bearing.
CAUTION:
Do not tap drive chain.
46. Install the front case assembly. Refer to TF-147, "Front Case" .
47. Install the rear case assembly. Refer to TF-146, "Rear Case" .

SMT988C

Front Case
1. Install the carrier bearing to the sun gear, using Tools.
Tool number A: ST30911000 ( — )
B: KV31103300 ( — )

SDIA2179E

Revision: October 2005 TF-174 2005 QX56

 TRANSFER ASSEMBLY

2. Install the snap ring to the sun gear assembly, using suitable
tool. A
CAUTION:
Do not reuse snap ring.
B

SDIA2148E
TF
3. Apply ATF to the circumference of the metal bushing and install
it to the sun gear assembly, using Tool.
Dimension A : 7.7 - 8.3 mm (0.303 - 0.327 in) E

Tool number : ST35300000 ( — )

CAUTION: F
● Do not reuse metal bushing.

● Apply ATF to metal bushing before installing.

G
WDIA0206E

4. Apply ATF to the needle bearing and install it to the sun gear H
assembly, using Tool.
Dimension B : 62.5 - 63.1 mm (2.461 - 2.484 in)
I
Tool number : ST33220000 ( — )
CAUTION:
● Do not reuse needle bearing. J
● Apply ATF to needle bearing before installing.

SDIA2478E K

5. Install the sun gear assembly to the planetary carrier assembly.

L

SDIA2180E

6. Install the snap ring to the planetary carrier assembly.

CAUTION:
Do not reuse snap ring.

SDIA2181E

Revision: October 2005 TF-175 2005 QX56

 TRANSFER ASSEMBLY

7. Set the mainshaft front bearing into the front case and install,
using Tool.
Tool number : ST30720000 (J-25405)

SDIA2172E

8. Install the snap ring into the front case.

CAUTION:
Do not reuse snap ring.

SDIA2171E

9. Install the internal gear with its groove facing the snap ring into
the front case. Then secure it with the snap ring.
CAUTION:
Do not reuse snap ring.

WDIA0100E

10. Install the oil seal until it is seated flush with the end face of the
front case, using Tool.
Tool number : KV38100500 ( — )
CAUTION:
● Do not reuse oil seal.

● Apply petroleum jelly to oil seal lip before installing.

SDIA2785E

11. Install the planetary carrier assembly and sun gear assembly to
the front case, using Tool.
Tool number : ST33200000 (J-26082)

SDIA2183E

Revision: October 2005 TF-176 2005 QX56

 TRANSFER ASSEMBLY

12. Install the snap ring to the sun gear assembly.

CAUTION: A
Do not reuse snap ring.

SDIA2144E

TF
13. Apply petroleum jelly to the circumference of the oil seal, and
install it to the front case, using Tools.
Dimension : 4.0 - 4.6 mm (0.157 - 0.181 mm) E

Tool number A: ST30720000 (J-25405)

B: ST33200000 (J-26082) F
CAUTION:
● Do not reuse oil seal.
● Apply petroleum jelly to oil seal. G
SDIA2786E

14. Install the fork guide, shift fork spring, 2-4 fork, and L-H fork to
H
the shift rod, and secure them with retaining pins.
CAUTION:
Do not reuse retaining pins.
I

SDIA2142E
K
15. Install the 2-4 sleeve and L-H sleeve to each fork.
16. Install the shift cross to the front case.
L

SMT992C

17. While aligning the L-H sleeve with the planetary carrier, install
the shift rod assembly to the front case.

SDIA2140E

Revision: October 2005 TF-177 2005 QX56

 TRANSFER ASSEMBLY

18. Apply liquid gasket to the entire center case mounting surface of
the front case assembly as shown.
● Use Genuine Anaerobic Liquid Gasket or equivalent.
Refer to GI-45, "Recommended Chemical Products and
Sealants" .
CAUTION:
Remove all foreign materials such as water, oil and grease
from center case and front case mating surfaces.

WDIA0157E

19. Install the center case assembly to the front case assembly.
CAUTION:
Do not damage mainshaft end.
20. Tap the center case lightly and press-fit the front drive shaft
bearing into the front case.

SDIA2138E

21. Tighten the front case bolts to the specified torque. Refer to TF-
144, "COMPONENTS" .
CAUTION:
Be sure to install air breather hose clamp, connector
bracket and harness clip.
22. Install the drain plug with a new gasket.
CAUTION:
Do not reuse gasket.

SDIA2100E

23. Align the matching mark on the front drive shaft with the mark on
the companion flange, then install the companion flange.

SDIA2779E

Revision: October 2005 TF-178 2005 QX56

 TRANSFER ASSEMBLY

24. Install the companion flange self-lock nut. Tighten to the speci-
fied torque, using Tool. Refer to TF-144, "COMPONENTS" . A
Tool number : KV40104000 ( — )
CAUTION: B
Do not reuse self-lock nut.

WDIA0219E
TF
25. Remove all the sealant from the check plug, switch mounting
and front case.
CAUTION: E
Remove old sealant adhering to mounting surfaces. Also
remove any moisture, oil, or foreign material adhering to
application and mounting surfaces.
F
26. Install the check ball and check spring to the front case. Apply
silicone gasket, to the check plug and wait detection switch and
install them to the front case. Tighten to the specified torque.
Refer to TF-144, "COMPONENTS" . G
● Use Genuine Silicone RTV or equivalent. Refer to GI-45, WDIA0158E

"Recommended Chemical Products and Sealants" .

H
NOTE:
Wait detection switch harness connector is black.
27. Install the oil seal in the front case, using Tool.
I
Tool number : ST22360002 (J-25679-01)
CAUTION:
● Do not reuse oil seal. J
● Apply petroleum jelly to seal lip before installing.

28. Install the shift lever to the shift cross.

29. Install the lock pin and lock pin nut. Tighten to the specified K
torque. Refer to TF-144, "COMPONENTS" .
SDIA2182E
L
Rear Case
1. Apply petroleum jelly to the circumference of the rear oil seal.
Install the rear oil seal so that it is flush with the case tip face, M
using Tool.
Tool number : ST30720000 (J-25405)
CAUTION:
● Do not reuse oil seal.
● Apply petroleum jelly to seal lip before installing.

SDIA2204E

Revision: October 2005 TF-179 2005 QX56

 TRANSFER ASSEMBLY

2. Apply petroleum jelly to the circumference of the dust cover.

Position the dust cover using the identification mark as shown.
CAUTION:
● Do not reuse dust cover.

● Position the identification mark at the position shown.

SDIA2208E

3. Install the dust cover, using Tool.

Tool number : KV40105310 ( — )
4. Install the air breather into the rear case.
5. Remove all the sealant from the rear case to center case mount-
ing surfaces.
CAUTION:
Remove all foreign materials such as water, oil, and grease
from center case and rear case mating surfaces.
6. Apply liquid gasket to the entire rear case mounting surface of
SDIA2205E
the center case.
● Use Genuine Anaerobic Liquid Gasket or equivalent. Refer to GI-45, "Recommended Chemical
Products and Sealants" .
CAUTION:
Do not to allow Liquid Gasket to enter stem bleeder hole.

7. Install the rear case to the center case. Tighten the bolts to the
specified torque. Refer to TF-144, "COMPONENTS" .

SDIA2092E

Revision: October 2005 TF-180 2005 QX56

 SERVICE DATA AND SPECIFICATIONS (SDS)

SERVICE DATA AND SPECIFICATIONS (SDS) PFP:00030

A
General Specifications EDS002J0

Applied model VK56DE

Transfer model ATX14B B

Fluid capacity (Approx.) (US qt, lmp qt) 3.0 (3-1/8, 2-5/8)
High 1.000 C
Gear ratio
Low 2.596

Planetary Sun gear 57

gear Internal gear 91 TF
Number of teeth
Front drive sprocket 38
Front drive shaft 38
E
Inspection and Adjustment EDS002J1

CLEARANCE BETWEEN INNER GEAR AND OUTER GEAR

Unit: mm (in) F
Item Specification
Sub-oil pump 0.015 - 0.035 (0.0006 - 0.0014)
G
Main oil pump 0.015 - 0.035 (0.0006 - 0.0014)

CLUTCH
Unit: mm (in) H
Item Limit value
Drive plate 1.4 (0.055)
I
PINION GEAR END PLAY
Unit: mm (in)
Item Standard
J
Pinion gear end play 0.1 - 0.7 (0.004 - 0.028)

CLEARANCE BETWEEN SHIFT FORK AND SLEEVE

Unit: mm (in) K
Item Standard
Shift fork and sleeve Less than 0.36 (0.0142)
L
SELECTIVE PARTS
Sub-oil Pump
Unit: mm (in) M
Part number*
Gear thickness
Inner gear Outer gear
9.27 - 9.28 (0.3650 - 0.3654) 31346 0W462 31347 0W462
9.28 - 9.29 (0.3654 - 0.3657) 31346 0W461 31347 0W461
9.29 - 9.30 (0.3657 - 0.3661) 31346 0W460 31347 0W460

*: Always check with the Parts Department for the latest parts information.

Main Oil Pump

Unit: mm (in)
Part number*
Gear thickness
Inner gear Outer gear
8.27 - 8.28 (0.3256 - 0.3260) 31346 7S112 31347 7S112
8.28 - 8.29 (0.3260 - 0.3264) 31346 7S111 31347 7S111
8.29 - 8.30 (0.3264 - 0.3268) 31346 7S110 31347 7S110

Revision: October 2005 TF-181 2005 QX56

 SERVICE DATA AND SPECIFICATIONS (SDS)

*: Always check with the Parts Department for the latest parts information.

Control Valve
Unit: mm (in)
Mounting position
Part number* Outer dia. Overall length
(Part name)
L1
31772 21X00 8.0 (0.315) 38.5 (1.516)
(2-4 shift valve)
L2
31772 80X11 10.0 (0.394) 40.0 (1.575)
(Clutch valve)
L4
31772 80X11 10.0 (0.394) 40.0 (1.575)
(Pilot valve)
L5
31741 0W410 12.0 (0.472) 68.0 (2.677)
(Regulator valve)
*: Always check with the Parts Department for the latest parts information.

Control Valve Spring

Unit: mm (in)
Mounting position
Part number* Free length Outer dia. Overall length
(Part name)
L1
31742 2W500 31.85 (1.2539) 7.0 (0.276) 0.6 (0.024)
(2-4 shift valve spring)
L2
31742 2W505 40.6 (1.598) 8.9 (0.350) 0.7 (0.028)
(Clutch valve spring)
L4
31742 0W410 28.1 (1.106) 9.0 (0.354) 1.2 (0.047)
(Pilot valve spring)
L5
31742 2W515 39.7 (1.563) 11.0 (0.433) 1.3 (0.051)
(Regulator valve spring)
*: Always check with the Parts Department for the latest parts information.

Return Spring
Unit: mm (in)
Stamped mark Part number* Free length
1 31521 7S111 42.7 (1.168)
2 31521 7S112 43.1 (1.697)
3 31521 7S113 43.6 (1.717)
4 31521 7S114 44.0 (1.731)

*: Always check with the Parts Department for the latest parts information.

Unit: mm (in)
Stamped mark Part number* Free length Outer dia. Overall length
L1
31742 2W500 31.85 (1.2539) 7.0 (0.276) 0.6 (0.024)
(2-4 shift valve spring)
L2
31742 2W505 40.6 (1.598) 8.9 (0.350) 0.7 (0.028)
(Clutch valve spring)
L4
31742 0W410 28.1 (1.106) 9.0 (0.354) 1.2 (0.047)
(Pilot valve spring)
L5
31742 2W515 39.7 (1.563) 11.0 (0.433) 1.3 (0.051)
(Regulator valve spring)

*: Always check with the Parts Department for the latest parts information.

Revision: October 2005 TF-182 2005 QX56