EG-60 ENGINE – 1UR-FSE ENGINE

JENGINE CONTROL SYSTEM

1. General
The engine control system of the 1UR-FSE engine has the following features.

System Outline
D A D-4S SFI system directly detects the intake air mass with a hot-wire
type mass air flow meters.
D The D-4S (Direct injection 4-stroke gasoline engine Superior version)
D-4S SFI
system is a fuel injection system which combines direct injection
 Sequential Multiport 
 Fuel Injection  injectors and port injection injectors.
  D Based on signals from each sensor, the ECM controls the injection
[See page EG-79]
volume and timing of each type of injector (direct and port injection
types) according to the engine speed and the engine load in order to
optimize combustion conditions.
D Ignition timing is determined by the ECM based on signals from
various sensors. The ECM corrects ignition timing in response to
ESA engine knocking.
 Electronic Spark Advance 
 
D This system selects the optimal ignition timing in accordance with the
signals received from the sensors and sends the ignition signal (IGT)
to the igniters.
ETCS-i
Optimally controls the throttle valve opening in accordance with the
 Electronic Throttle Control 
 System-intelligent  amount of accelerator pedal effort and the conditions of the engine and
  the vehicle.
[See page EG-82]
D Controls the intake and exhaust camshafts to an optimal valve timing
Dual VVT-i
 Variable Valve  in accordance with the engine conditions.
  D The intake side is VVT-iE and uses an electric motors to control the
 Timing-intelligent 
valve timing. The exhaust side is VVT-i and uses engine oil pressure
[See page EG-85]
to control the valve timing.
ACIS
The intake air passages are switched according to the engine speed and
 Acoustic Control 
  throttle valve opening angle to provided high performance in all speed
 Induction System  ranges.
[See page EG-95]
For High Regulates the fuel pressure within a range of 4 to 13 MPa in accordance
Fuel Pressure Side with the driving conditions.
Pump For Low D Fuel pump operation is controlled by signals from the ECM.
Control Pressure Side D The fuel pump is stopped, when the SRS airbag is deployed in a frontal,
[See page EG-97] side, or rear side collision.
Air Fuel Ratio Sensor Maintains the temperature of the air fuel ratio sensors and heated oxygen
and Heated Oxygen Sensor sensors at an appropriate level to increase accuracy of detection of the
Heater Control oxygen concentration in the exhaust gas.
Air Conditioning By turning the air conditioning compressor ON or OFF in accordance
Cut-off Control with the engine condition, drivability is maintained.
The cooling fan ECU steplessly controls the speed of the fans in
Cooling Fan Control accordance with the engine coolant temperature, vehicle speed, engine
[See page EG-98] speed, and air conditioning operating conditions. As a result, the cooling
performance is improved.
Starter Control
 Cranking Hold Function 
Once the engine switch is pushed, while the brake pedal is depressed, this
control continues to operate the starter until the engine started.
[See page EG-100]
(Continued)
 ENGINE – 1UR-FSE ENGINE EG-61

System Outline
D The ECM lowers the generated voltage when the vehicle is idling or
is being driven at a constant speed, and raises the generated voltage
when the vehicle is decelerating. This reduces the load on the engine,
Charging Control Function
contributing to the fuel economy of the engine.
D This function is one of the functions of the electric power control
system. For details, see page BE-32.
Oil Replacement Reminder* Based on the driven distance of the vehicle, the ECM reminds the driver
[See page EG-102] of the need to replace the engine oil via the multi-information display.
D The ECM controls the purge flow of evaporative emission (HC) in the
canister in accordance with the engine conditions.
Evaporative Emission EG
D Approximately five hours after the power source has been turned OFF,
Control
the ECM operates the pump module to detect any evaporative
[See page EG-104]
emission leakage occurring between the fuel tank and the canister
through changes in the fuel tank pressure.
Prohibits fuel delivery and ignition if an attempt is made to start the
Engine Immobilizer
engine with an invalid key.
Diagnosis When the ECM detects a malfunction, the ECM diagnoses and
[See page EG-116] memorizes the failed section.
Fail-Safe When the ECM detects a malfunction, the ECM stops or controls the
[See page EG-116] engine according to the data already stored in the memory.
*: Only for U.S.A. models
EG-62 ENGINE – 1UR-FSE ENGINE

2. Construction
The configuration of the engine control system is as shown in the following chart.
MASS AIR FLOW METER SFI (For Direct Injection)

VG #1 IJ1
Bank 1 No. 1 Injector
VG2 #4 IJ4
Bank 2 No. 4 Injector
#6 IJ6
No. 1 No. 6 Injector
#7 Injector IJ7
Driver No. 7 Injector
FPF1
INTAKE AIR TEMP. SENSOR (EDU)
INJ1
THA FUEL PUMP CONTROL
Bank 1 INJ2 (For High Pressure Side)
THA2
Bank 2 FPD FP
Spill Control Valve (Bank 1)

IREL
CRANKSHAFT POSITION NE Injector No. 1 Relay (Power Distributor)
SENSOR

SFI (For Direct Injection)

CAMSHAFT POSITION G2 #2 IJ2
SENSOR No. 2 Injector
#3 IJ3
No. 3 Injector
#5 No. 2 IJ5
ENGINE COOLANT THW Injector IJ8 No. 5 Injector
#8
TEMPERATURE SENSOR Driver No. 8 Injector
FPF2 (EDU)
INJ3
FUEL PUMP CONTROL
FUEL PRESSURE SENSOR PR ECM INJ4 (For High Pressure Side)
(For High Pressure Side)
FPD2 FP2
Spill Control Valve (Bank 2)

AIR FUEL RATIO SENSOR

IREL
A1A Injector No. 2 Relay (Power Distributor)
Bank 1, Sensor 1
A2A
Bank 2, Sensor 1
SFI (For Port Injection)

#10X#80 No. 1, 2, 3, 4, 5, 6, 7, 8
HEATED OXYGEN SENSOR Injector
OX1B
Bank 1, Sensor 2
OX2B ESA
Bank 2, Sensor 2
IGT1, 4, 6, 7
No. 1, 4, 6, 7
IGF1
Ignition Coil with Igniter
KNOCK SENSOR
No. 1, 4, 6, 7 Spark Plug
KNK2
Bank 1, Sensor 1 IGT2, 3, 5, 8
KNK4 No. 2, 3, 5, 8
Bank 1, Sensor 2 IGF2
Ignition Coil with Igniter
KNK1
Bank 2, Sensor 1
KNK3
Bank 2, Sensor 2 No. 2, 3, 5, 8 Spark Plug

036EG146TE
(Continued)
 ENGINE – 1UR-FSE ENGINE EG-63

ACCELERATOR PEDAL VPA ETCS-i

POSITION SENSOR VPA2
M
Throttle Control Motor

THROTTLE POSITION VTA VVT-iE (Intake Side)

SENSOR VTA2 EDT1
EMR1
EMF1
Camshaft Control Motor
(Bank 1)
S EMD1
TRANSMISSION SFTU
CONTROL SWITCH SFTD VVT No. 1 Relay
EDT2 EG
EMR2
Camshaft Control Motor
EMF2 (Bank 2)
CCS EMD2
CRUISE CONTROL SWITCH

VVT No. 2 Relay

INTAKE VVT SENSOR VVT-i (Exhaust Side)

Bank 1 VV1 OE1 Camshaft Timing

VV2 Oil Control Valve (Bank 1)
Bank 2
ECM OE2 Camshaft Timing
Oil Control Valve (Bank 2)

EXHAUST VVT SENSOR ACIS

EV1 ASM
Bank 1 ACIS Actuator
EV2
Bank 2
FUEL PUMP CONTROL
(For Low Pressure Side)
FC
Circuit Opening Relay
COMBINATION METER SPD FPR
Fuel Pump Relay
D Vehicle Speed Signal*

AIR FUEL RATIO SENSOR

HEATER CONTROL
HA1A
STP A/ F Sensor Heater (Bank 1)
STOP LIGHT SWITCH

A/ F Relay (Power Distributor)

HA2A
A/ F Sensor Heater (Bank 2)
PARK / NEUTRAL NSW
POSITION SWITCH P, R, N, D
HEATED OXYGEN SENSOR
HEATER CONTROL
HT1B
IMI Oxygen Sensor Heater (Bank 1)
HT2B
ID CODE BOX IMO Oxygen Sensor Heater (Bank 2)

036EG150TE
(Continued)
EG-64 ENGINE – 1UR-FSE ENGINE

ENGINE SWITCH STARTER CONTROL

STSW
ACCR
MAIN BODY ECU Main Body ECU

IGSW ACC Relay

IG2 RELAY
STAR
Starter Cut Relay

MREL
Park / Neutral Position Switch
EFI MAIN RELAY +B
STA
Starter Relay

BATT
BATTERY CHARGING CONTROL
+BM
ALT
ECM RLO Generator
CAN
ECT ECU (Powertrain Bus)
CAN+
D Vehicle Speed Signal* CAN– EVAPORATIVE EMISSION
D Cooperative Control Signal CONTROL

Canister Pump Module

MPMP
SKID CONTROL ECU CA2H Leak Detection Pump
VPMP
Vent Valve
D Cooperative Control Signal CA2L PPMP
CAN Canister Pressure Sensor
(Braking and
Driving Bus)
PRG
Purge VSV
DRIVING SUPPORT ECU
Dynamic Radar type Cruise Control
COMBINATION METER
W
MIL (Malfunction Indicator Lamp)
TC
DLC3 CANH Multi-information Display
(Data Link Connector 3)
CANL
Meter ECU
CAN (V Bus)
AIRBAG SENSOR
ASSEMBLY
COOLING FAN CONTROL

FRONT CONTROLLER Cooling Fan ECU

AIR CONDITIONING ECU
CAN (MS Bus) Fan Motor Main, Sub

MAIN BODY ECU

ELECTRIC POWER
CONTROL ECU
036EG151TE

*: The vehicle speed signal which is used for the engine control is sent from the ECT ECU.
 ENGINE – 1UR-FSE ENGINE EG-65

3. Engine Control System Diagram

Engine Switch Front Controller

CAN (MS Bus) Combination Meter (Meter ECU)
D MIL
Main Body ECU D Multi-information Display Cooling Fan
ECU
IG2 Relay Electric Power Control ECU
Fan Motor Main, Sub
Starter Cut Relay
Battery Air Conditioning ECU Skid Control ECU
Starter Relay ECT

Circuit Airbag Sensor Assembly Driving Support ECU Park / Neutral

Fuel Pump Opening Position Switch
Resistor
Relay
DLC3 ECT ECU
Fuel Pump CAN
Relay CAN Stop Accelerator
CAN (Braking and (Powertrain
Light Pedal
(V Bus) Driving Bus) Bus)
Switch
Position EG
Sensor

ECM

Injector No. 2 Injector No. 1

Relay (Power Relay (Power
Distributor) Mass Air Mass Air Distributor)
Flow Meter Flow Meter
Intake Air Temp. Intake Air Temp.
No. 2 Injector Sensor Sensor No. 1 Injector
Driver (EDU) Driver (EDU)

Throttle Position Sensor Throttle Control Motor

Purge VSV

Injector (For Direct Injection) Fuel Pressure Sensor

Injector (For Port Injection) Injector (For Direct Injection)
Intake VVT Sensor Injector (For Port Injection)
ACIS
Camshaft Position Sensor Intake VVT Sensor
Actuator
Fuel Pump (For High Pressure) Fuel Pump (For High Pressure)
Camshaft Control Motor Camshaft Control Motor

Ignition Coil with Igniter Ignition Coil with Igniter

Exhaust VVT Sensor Exhaust VVT Sensor
Camshaft Timing OCV Camshaft Timing OCV

Air Fuel Ratio Sensor Air Fuel Ratio Sensor

TWC TWC

Heated Oxygen Sensor Heated Oxygen Sensor

Knock Sensor Knock Sensor

Crankshaft Position Sensor Engine Coolant Temp. Sensor
TWC TWC

Canister Pump Module

D Leak Detection Pump Fuel Pump
D Vent Valve
D Canister Pressure Sensor 036EG147TE
EG-66 ENGINE – 1UR-FSE ENGINE

4. Layout of Main Components

MIL (Malfunction Indicator Lamp)
Multi-information Display Electric Power Control ECU

Engine Switch

Combination Meter (Meter ECU)

Stop Light Switch

Main Body ECU

Driving Support ECU

Engine Room R / B No. 2

(Power Distributor)
DLC3

Accelerator Pedal Airbag Sensor Assembly

Position Sensor
IG2 Relay
IG1 Relay
EFI Main Relay
Starter Relay EFI Main No. 2 Relay
Circuit Opening Relay
VVT No. 2 Relay Canister Pump Module
Fuel Pump Relay
Starter Cut Relay Fuel Pump D Vent Valve
VVT No. 1 Relay (For Low Pressure) D Leak Detection Pump
D Pressure Sensor
Mass Air Flow Meter (Bank 1, Bank 2)
D Intake Air Temp. Sensor

Fan No. 1
Relay
Skid Control ECU

Heated Oxygen Sensor (Bank 2, Sensor2)

Front Heated Oxygen Sensor (Bank 1, Sensor2)
Controller
Air Fuel Ratio Sensor (Bank 1, Sensor 1)
Cooling Fan ECU Air Fuel Ratio Sensor (Bank 2, Sensor 1)
ECM Fuel Pump Resistor
ECT ECU
036EG148TE
 ENGINE – 1UR-FSE ENGINE EG-67

Knock Sensor Bank 1, Sensor 2

No. 1 Injector Driver (EDU)
Knock Sensor Bank 2, Sensor 2
No. 2 Injector Driver (EDU)
Knock Sensor Bank 1, Sensor 1
Knock Sensor Bank 2, Sensor 1
Purge VSV

Camshaft Position Fuel Pump Bank 1

Sensor (For High Pressure)

Camshaft Control
Motor Bank 2 EG
Ignition Coil
with Igniter
Throttle Body
D Throttle Position Sensor
D Throttle Control Motor
Intake VVT
Sensor Bank 1
Engine Coolant
Temperature Sensor
Exhaust VVT
Sensor Bank 1
Camshaft Control
Motor Bank 1
Camshaft Timing
Oil Control Valve Bank 1

ACIS Actuator
Camshaft Timing
Oil Control Valve Bank 2

Intake Air
Control Valve

Fuel Pressure Sensor

Intake VVT
Sensor Bank 2
Injector
(For Direct Injection) Exhaust VVT
Sensor Bank 2

Fuel Pump Bank 2

(For High Pressure)
Injector
(For Port Injection)

Crankshaft Position Sensor 036EG108TE

EG-68 ENGINE – 1UR-FSE ENGINE

5. Main Component of Engine Control System

General
The main components of the 1UR-FSE engine control system are as follows:

Components Outline Quantity Function

The ECM optimally controls the SFI, ESA and
ISC to suit the operating conditions of the
ECM 32-bit CPU 1
engine in accordance with the signals provided
by the sensors.
Mass Air Flow Meter This sensor has a built-in hot-wire to directly
Hot-wire Type 2
[See page EG-69] detect the intake air mass.
Intake Air Temperature This sensor detects the intake air temperature
Thermistor Type 2
Sensor by means of an internal thermistor.
Crankshaft Position
MRE Type This sensor detects the engine speed and the
Sensor 1
(Rotor Teeth/36-2) crankshaft position.
[See page EG-70]
Camshaft Position
MRE Type This sensor detects the camshaft position and
Sensor 1
(Rotor Teeth/3) performs the cylinder identification.
[See page EG-70]
Intake VVT Sensor MRE Type 1 each
This sensor detects the actual valve timing.
[See page EG-70] (Rotor Teeth/3) bank
Exhaust VVT Sensor MRE Type 1 each
This sensor detects the actual valve timing.
[See page EG-70] (Rotor Teeth/3) bank
Accelerator Pedal
Hall IC Type This sensor detects the amount of pedal effort
Position Sensor 1
(No-contact Type) applied to the accelerator pedal.
[See page EG-73]
Throttle Position
Hall IC Type This sensor detects the throttle valve opening
Sensor 1
(No-contact Type) angle.
[See page EG-74]
Built-in This sensor detects an occurrence of the
Knock Sensor Piezoelectric 2 each engine knocking indirectly from the vibration
[See page EG-75] Element bank of the cylinder block caused by the occurrence
(Flat Type) of engine knocking.
This sensor detects the oxygen concentration
Heated Oxygen Sensor Cup Type 1 each in the exhaust emission by measuring the
[See page EG-77] with Heater bank electromotive force which is generated in the
sensor itself.
As with the oxygen sensor, this sensor detects
Air Fuel Ratio Sensor Planar Type 1 each the oxygen concentration in the exhaust
[See page EG-77] with Heater bank emission. However, it detects the oxygen
concentration in the exhaust emission linearly.
This sensor detects the engine coolant
Engine Coolant
Thermistor Type 1 temperature by means of an internal
Temperature Sensor
thermistor.
Injector This injector contains an electro-magnetically
(For Port Injection) 12-hole Type 8 operated nozzle to inject fuel into the intake
[See page EG-46] port.
Injector High Pressure This injector contains a high-pressure
(For Direct Injection) Double Slit 8 electro-magnetically operated nozzle to inject
[See page EG-47] Nozzle Type fuel directly into the cylinder.
(Continued)
 ENGINE – 1UR-FSE ENGINE EG-69

Components Outline Quantity Function

The injector driver converts the signals from
Injector Driver (EDU) Built-in DC/DC the ECM into high-voltage, high-amperage
2
[See page EG-47] Converter current in order to drive the direct injection
injectors.
The rotational movement of the camshaft
Camshaft Control EDU-integrated control motor changes the intake valve timing
1 each
Motor (Brushless Type by operating the camshaft control actuator in
bank
[See page EG-89] DC Motor) accordance with the signals received from the
ECM.
The camshaft timing oil control valve changes
EG
Camshaft Timing the exhaust valve timing by switching the oil
Electro-Magnetic 1 each
Oil Control Valve passage that acts on the VVT-i controller in
Coil Type bank
[See page EG-93] accordance with the signals received from the
ECM.

Mass Air Flow Meter

D This mass air flow meter, which is a plug-in type, allows a portion of the intake air to flow through the
detection area. By directly measuring the mass and the flow rate of the intake air, the detection precision
is improved and the intake air resistance is reduced.
D This mass air flow meter has a built-in intake air temperature sensor.

Intake Air Temperature

Sensor
Air Flow

Temperature
Sensing Element
Platinum Hot-Wire
Element 036EG101TE
EG-70 ENGINE – 1UR-FSE ENGINE

Crankshaft Position and Camshaft Position and VVT Sensors

1) General
D The MRE (Magnetic Resistance Element) sensors are used for the crankshaft position, camshaft
position, and VVT sensors.
D The timing rotor for the crankshaft position sensor is installed on the back end of the crankshaft. The
timing rotor has 34 teeth, with 2 teeth missing, at 10_ intervals. Based on these teeth, the crankshaft
position sensor transmits crankshaft position signals (NE signal) consisting of 33 Hi/Lo output pulses
every 10_ per revolution of the crankshaft, and 1 Hi/Lo output pulse every 30_. The ECM uses the
NE signal for detecting the crankshaft position as well as for detecting the engine speed. It uses the
missing teeth signal for determining the top-dead-center.
D The camshaft position sensor uses a timing rotor that is installed on the front end of the intake camshaft
sprocket of the right bank. Based on the timing rotor, the sensor outputs camshaft position signals (G2
signal) consisting of 6 (3 Hi output, 3 Lo output) pulses for every 2 revolutions of the crankshaft. The
ECM compares the G2 and NE signals to detect the camshaft position and identify the cylinder.
D The intake and exhaust VVT sensors use timing rotors that are installed on the intake and exhaust
camshafts of each bank. Based on the timing rotors, the sensors output VVT position signals consisting
of 6 (3 Hi output, 3 Lo output) pulses for every 2 revolutions of the crankshaft. The ECM compares
these VVT position signals to the NE signal to detect the actual valve timing.
Camshaft Position Sensor Intake VVT Sensor (Bank 1)
Timing Rotor

Timing Rotor Timing Rotor

Exhaust VVT sensor (Bank 1)

Crankshaft Position Sensor

Timing Rotor
036EG109TE
 ENGINE – 1UR-FSE ENGINE EG-71

" Wiring Diagram A

VC

Crankshaft NE+
Position Sensor ECM
NE–

Timing Rotor 036EG110TE EG

Crankshaft Position Sensor Circuit

" Sensor Output Waveforms A

VVT Sensor Signal Plate (720_ CA)

VVT Variable Timing Range

VVT 230_ CA 230_ CA 140_ CA

40_ 40_ 40_
Sensor* CA CA CA

Camshaft Position Sensor Signal Plate (720_ CA)

Camshaft 120_ CA 60_ CA 180_ CA

Position
Sensor 60_ CA 180_ CA 120_ CA

360_ CA 360_ CA
10_ CA 30_ CA
Crankshaft
Position
Sensor

036EG111TE

*: This is an example of an output waveform of the intake VVT sensor (bank 2).
EG-72 ENGINE – 1UR-FSE ENGINE

2) MRE Type Sensor

D The MRE type sensor consists of an MRE, a magnet and a sensor.
D The direction of the magnetic field changes due to the different shapes (protruded and non-protruded
portions) of the timing rotor, which passes by the sensor. As a result, the resistance of the MRE
changes, and the output voltage to the ECM changes to Hi or Lo. Based on the switching timing of
the Hi/Lo output voltage, the ECM detects the positions of the crankshaft and camshaft.
D The differences between the MRE type sensor and the pick-up coil type sensor used on a conventional
model are as follows.
– An MRE type sensor outputs a constant level of Hi/Lo digital signals regardless of the engine
speed. Therefore, an MRE type sensor can detect the positions of the crankshaft and camshaft at
an early stage of cranking.
– A pickup coil type sensor outputs analog signals with levels that change with engine speed.

" MRE Type and Pick-up Coil Type Output Waveform Image Comparison A

No Detection
Engine Engine
Speed Speed

Analog
Output
Digital
Output Sensor
Sensor Output
Output

MRE Type Pick-up Coil Type

232CH41
 ENGINE – 1UR-FSE ENGINE EG-73

Accelerator Pedal Position Sensor

D The no-contact type accelerator pedal position sensor uses a Hall IC, which is mounted on the accelerator
pedal arm.
D A magnetic yoke is mounted at the base of the accelerator pedal arm. This yoke rotates around the Hall
IC in accordance with the amount of effort that is applied to the accelerator pedal. The Hall IC converts
the changes that occur in the magnetic flux into electrical signals, and outputs them in the form of
accelerator pedal position signals to the ECM.
D The Hall IC contains two circuits, one for the main signal, and one for the sub signal. It converts the
accelerator pedal position (angle) into electric signals that have differing characteristics and outputs them
to the ECM.
EG

Magnetic Yoke

Hall IC
Accelerator Pedal Arm

036EG167S

Accelerator Pedal
Position Sensor
Magnet V
VPA 5
EPA
Hall Output VPA2
VCPA Voltage
IC ECM
VPA2 VPA
Hall
IC
EPA2 0
VCP2 Accelerator Pedal
Fully Position (Angle) Fully
Magnet Close Open

228TU24 0140EG126C

Service Tip
The inspection method differs from a conventional accelerator pedal position sensor because this
sensor uses a Hall IC. For details, refer to the 2007 LEXUS LS460L/LS460 Repair Manual (Pub.
No. RM0360U).
EG-74 ENGINE – 1UR-FSE ENGINE

Throttle Position Sensor

D The no-contact type throttle position sensor uses a Hall IC, which is mounted on the throttle body.
D The Hall IC is surrounded by a magnetic yoke. The Hall IC converts the changes that occur in the
magnetic flux at that time into electrical signals and outputs them in the form of a throttle valve effort
to the ECM.
D The Hall IC contains circuits for the main and sub signals. It converts the throttle valve opening angles
into electric signals with two differing characteristics and outputs them to the ECM.

Throttle Position
Sensor Portion

Throttle Body
View from A

Magnet

Hall IC

Magnet
036EG102TE

Cross Section
Throttle Position Sensor

Magnet
V
VTA 5
VTA2
Hall ETA
IC Output
ECM
VCTA Voltage VTA
Hall
IC
VTA2
0
10 20 30 40 50 60 70 80 90

Fully Throttle Valve Fully

Magnet Opening Angle
Close Open
02HEG57Y

Service Tip
The inspection method differs from a conventional throttle position sensor because this sensor uses
a Hall IC. For details, refer to the 2007 LEXUS LS460L/LS460 Repair Manual (Pub. No.
RM0360U).
 ENGINE – 1UR-FSE ENGINE EG-75

Knock Sensor (Flat Type)

1) General
In the conventional type knock sensor (resonant type), a vibration plate, which has the same resonance
point as the knocking frequency of the engine, is built-in and can detect the vibration in this frequency
band.
On the other hand, a flat type knock sensor (non-resonant type) has the ability to detect vibration in a
wider frequency band from about 6 kHz to 15 kHz, and has the following features:
D The engine knocking frequency will change a bit depending on the engine speed. The flat type knock
sensor can detect vibration even when the engine knocking frequency is changed. Thus the vibration
detection ability is increased compared to the conventional type knock sensor, and a more precise
ignition timing control is possible. EG

: Conventional Type
: Flat Type

(V) A: Detection Band of

A Conventional Type
B: Detection Band of
Flat Type
Voltage

Frequency (Hz) 214CE04

Characteristic of Knock Sensor

2) Construction
D The flat type knock sensor is installed on the engine through the stud bolt installed on the cylinder
block. For this reason, a hole for the stud bolt is running through in the center of the sensor.
D Inside of the sensor, a steel weight is located on the upper portion and a piezoelectric element is located
under the weight through the insulator.
D The open/short circuit detection resistor is integrated.

Open/Short Circuit
Detection Resistor Piezoelectric
Steel Weight Element
Insulator
Vibration Plate
Piezoelectric
Element
214CE01
214CE02

Flat Type Knock Sensor Conventional Type Knock Sensor

(Non-Resonant Type) (Resonant Type)
EG-76 ENGINE – 1UR-FSE ENGINE

3) Operation
The knocking vibration is transmitted to the
steel weight and its inertia applies pressure to Steel Weight
the piezoelectric element. The action
generates electromotive force. Inertia

Piezoelectric
Element

214CE08

4) Open/Short Circuit Detection Resistor

During the power source is IG-ON, the open/short circuit detection resistor in the knock sensor and the
resistor in the ECM keep the voltage at the terminal KNK1 of engine constant.
An IC (Integrated Circuit) in the ECM is always monitoring the voltage of the terminal KNK1. If the
open/short circuit occurs between the knock sensor and the ECM, the voltage of the terminal KNK1 will
change and the ECM detects the open/short circuit and stores DTC (Diagnostic Trouble Code).

Piezoelectric ECM
Element 5V
Flat Type Knock Sensor
200 kΩ
KNK1
IC
200 kΩ
EKNK

Open/Short Circuit
Detection Resistor 214CE06

Service Tip
These knock sensors are mounted in the specific directions and angles as illustrated. For details,
refer to the 2007 LEXUS LS460L/LS460 Repair Manual (Pub. No. RM0360U).
Knock Sensor (Bank 2, Sensor 1) Knock Sensor (Bank 2, Sensor 2)

Engine
Front

036EG104TE

Knock Sensor (Bank 1, Sensor 1) Knock Sensor (Bank 1, Sensor 2)

 ENGINE – 1UR-FSE ENGINE EG-77

Air Fuel Ratio Sensor and Heated Oxygen Sensor

1) General
D The heated oxygen sensor and the air fuel ratio sensor differ in output characteristics.
D The output voltage of the heated oxygen sensor changes in accordance with the oxygen concentration
in the exhaust gas. The ECM uses this output voltage to determine whether the present air-fuel ratio
is richer or leaner than the stoichiometric air-fuel ratio.
D Approximately 0.4 V is constantly applied to the air fuel ratio sensor, which outputs an amperage that
varies in accordance with the oxygen concentration in the exhaust gas. The ECM converts the changes
in the output amperage into voltage in order to linearly detect the present air-fuel ratio.
EG

A1A+ OX1B
(3.3 V) (0.1X1.0 V)

Air Fuel Heated

Ratio ECM Oxygen ECM
Sensor Sensor

A1A– E2
(2.9 V)

02HEG56Y

Air Fuel Ratio Sensor Circuit Heated Oxygen Sensor Circuit

: Air Fuel Ratio Sensor

: Heated Oxygen Sensor
(V) 4.2 1.0 (V)

Air Fuel Ratio

Sensor Output* Heated Oxygen
 Data Displayed on  Sensor Output
 Hand-held Tester/ 
 
 Techstream 

2.2 0.1

11 (Rich) 14.7 19 (Lean) D13N11

Air-Fuel Ratio

*: This calculation value is used internally in the ECM, and is not an ECM terminal voltage.
EG-78 ENGINE – 1UR-FSE ENGINE

2) Construction
D The basic construction of the heated oxygen sensor and the air fuel ratio sensor is the same. However,
they are divided into the cup type and the planar type, according to the different types of heater
construction that are used.
D The cup type sensor contains a sensor element that surrounds a heater.
D The planar type sensor uses alumina, which excels in heat conductivity and insulation, to integrate a
sensor element with a heater, thus improving the warm up performance of the sensor.

Heater
Alumina Platinum
Dilation Layer Electrode Atmosphere
Atmosphere

Alumina

Heater

Platinum
Electrode
Sensor Element (Zirconia) Sensor Element (Zirconia)

Planar Type Air Fuel Ratio Sensor Cup Type Heated Oxygen Sensor
036EG152Z
 ENGINE – 1UR-FSE ENGINE EG-79

6. D-4S SFI (Sequential Multiport Fuel Injection) System

General
D A D-4S (Direct injection 4-stroke gasoline engine Superior version) SFI system directly detects the
intake air mass with a hot-wire type mass air flow meters.
D The D-4S system is a fuel injection system which combines direct injection injectors and port injection
injectors.
D Based on signals from each sensor, the ECM controls the injection volume and timing of each type of
injector (direct and port injection types) according to engine load and engine speed in order to optimize
combustion conditions.
D To promote warm up of the catalyst after a cold engine start, this system uses a stratified air-fuel mixture, EG
that results in an area near the spark plug that is richer than the rest of the air-fuel mixture. This allows
a retarded ignition timing to be used so the exhaust gas temperature can be increased. This results in more
rapid heating of the catalytic converters, reducing exhaust emissions.

Heavy

Engine
Load Direct Injection
Direct Injection
+
Port Injection

Engine Speed High

Fuel Injection System Activation Ranges

036EG166TE
EG-80 ENGINE – 1UR-FSE ENGINE

Stratification Combustion
Immediately after a cold engine start, fuel is injected into the intake port from the port injection injector
during the exhaust stroke. Fuel is also injected from the direct injection injector near the end of the
compression stroke. This results in the air-fuel mixture that is stratified, the area near the spark plug is richer
than the rest of the air-fuel mixture. This allows a retarded ignition timing to be used, raising the exhaust
gas temperature. The increased exhaust gas temperatures promote rapid warm up of the catalysts, and
significantly improve exhaust emission performance.

1) Exhaust stroke
Fuel is injected into the intake port from the
port injection injector before the intake valves
open.

2) Intake stroke
The intake valves open and a homogeneous
air-fuel mixture is drawn into the combustion
chamber.

3) Compression stroke
Fuel is injected into the combustion chamber
from the direct injection injector near the end
of compression stroke.

4) Ignition to combustion stroke

Injected fuel is directed along the piston
contour to the area near the spark plug. This
produces a combustible area of the rich
air-fuel mixture that allows for easy ignition.
This allows combustion of a lean air-fuel
mixture to occur.
Lean Rich
036EG112TE
 ENGINE – 1UR-FSE ENGINE EG-81

Homogeneous Combustion
To optimize combustion conditions, the ECM controls injection volume and timing of the port injection
injectors which inject fuel into the intake ports during the expansion, exhaust, and intake strokes. The ECM
also controls the injection volume and timing of the direct injection injectors which inject fuel during the
first half of the intake stroke. The homogeneous air-fuel mixture is created by either combined or individual
use of the two different types of injectors. This allows utilization of the heat of evaporation of the injected
fuel to cool the compressed air, it also allows an increase of charging efficiency and power output.

1) Exhaust stroke
Fuel is injected into the intake port from the
port injection injector before the intake valves EG
open.

2) Intake stroke
The intake valves open to allow the
homogeneous air-fuel mixture into the
combustion chamber, and fuel is injected into
the combustion chamber from the direct
injection injector during the first half of the
intake stroke. The injected fuel and air are
evenly mixed by intake air force.

3) Compression stroke
The homogeneous air-fuel mixture is
compressed.

4) Ignition to combustion stroke

The spark plug ignites the homogeneous
air-fuel mixture.

036EG113TE
EG-82 ENGINE – 1UR-FSE ENGINE

7. ETCS-i (Electronic Throttle Control System-intelligent)

General
D In the conventional throttle body, the throttle valve angle is determined invariably by the amount of the
accelerator pedal effort. In contrast, ETCS-i uses the ECM to calculate the optimal throttle valve angle
that is appropriate for the respective driving condition and uses a throttle control motor to control the
angle.
D In case of an abnormal condition, this system transfers to the fail-safe mode. For details, see page
EG-117.

" System Diagram A

Accelerator Pedal Position Sensor Throttle Valve Throttle Position Sensor

Throttle Control Motor

Mass Air Flow Meter No. 1 to 8

(Bank 1, Bank 2) Ignition Coil with Igniter

Crankshaft Position Sensor No. 1 to 8 Injector

(For Port Injection)
ECT ECU CAN
(Powertrain Bus)
D Vehicle Speed Signal ECM No. 1 Injector Driver (EDU)
D Cooperative Control Signal

No. 1, 4, 6, 7 Injector
Cruise Control Switch*1 (For Direct Injection)
CAN
(V Bus)
Main Body ECU
No. 2 Injector Driver (EDU)
(Gateway Function)
CAN
(MS Bus)
CAN No. 2, 3, 5, 8 Injector
Driver Side Switch Module (Braking and Driving Bus)
(For Direct Injection)
(Gateway Function)
Skid Control ECU
LIN
(Local Interconnect D Cooperative Control Signal
Network)
CAN
Millimeter Wave
Center Console Switch Module
(Parking Assist Bus) Radar Sensor*2
Pattern Select Switch
(SNOW Mode) Driving Support ECU*2 Cruise Control Switch*2

036EG153TE
*1: Without Dynamic Radar type Cruise Control system
*2: With Dynamic Radar type Cruise Control system
 ENGINE – 1UR-FSE ENGINE EG-83

Control

1) General
The ETCS-i consists of the following functions:
D Normal Throttle Control (Non-linear Control)
D ISC (Idle Speed Control)
D Powertrain Cooperative Control
D TRAC (Traction Control)
D VSC (Vehicle Stability Control)
D Cruise Control
D Dynamic Radar type Cruise Control* EG
*: With Dynamic Radar type Cruise Control system

2) Normal Throttle Control (Non-linear Control)

a. Normal-mode Control
Controls the throttle to an optimal throttle valve angle that is appropriate for the driving condition such
as the amount of the accelerator pedal effort and the engine speed in order to realize excellent throttle
control and comfort in all operating ranges.

" Conceptual Diagrams of Engine Control During Acceleration and Deceleration A

: With Control
"
: Without Control
Vehicle’s
Longitudinal G
0

"
Ignition Timing
0
"
Throttle Valve
Opening Angle
0
"
Accelerator Pedal
Depressed Angle
0
Time ! 00MEG38Y

b. Snow-mode Control
In situations in which low-µ (low friction) road surface conditions can be anticipated, such as when
driving in the snow, the rate of throttle valve opening can be controlled to help vehicle stability while
driving on the slippery surface. This is accomplished by turning on SNOW mode. Pressing the SNOW
side of the pattern select switch activates this mode. This mode modifies the relationship and reaction
of the throttle to the accelerator pedal, and assists the driver by reducing the engine output from that
of a normal level.
EG-84 ENGINE – 1UR-FSE ENGINE

3) Idle Speed Control

The ECM controls the throttle valve in order to constantly maintain an ideal idle speed.

4) Powertrain Cooperative Control

The ECM effects cooperative control with the ECT ECU in order to control the throttle valve at a position
that is optimal for the driving conditions. Thus, it ensures a quick response to the driver’s accelerator
pedal effort and reduces shift shocks.

5) TRAC Throttle Control

As part of the TRAC function, the throttle valve is closed by a demand signal from the skid control ECU
if an excessive amount of slippage is created at a driving wheel, thus facilitating the vehicle in ensuring
excellent vehicle stability and driving force.

6) VSC Coordination Control

In order to bring the effectiveness of the VSC function control into full play, the throttle valve angle is
controlled by effecting a coordination control with the skid control ECU.

7) Cruise Control
An ECM with an integrated cruise control ECU directly actuates the throttle valve for operation of the
cruise control.

8) Dynamic Radar type Cruise Control

The dynamic radar type cruise control uses a millimeter wave radar sensor and the driving support ECU
to determine the distance of the vehicle driven ahead, its direction, and relative speed. Thus, the system
can effect deceleration cruising control, follow up cruising control, cruising at a fixed speed control, and
acceleration cruising control. To make these controls possible, the ECM controls the throttle valve.
 ENGINE – 1UR-FSE ENGINE EG-85

8. Dual VVT-i (Variable Valve Timing-intelligent) System

General
D The Dual VVT-i system is designed to control the intake and exhaust camshafts within a range of 40_
and 35_ respectively (of crankshaft angle) to provide valve timing that is optimally suited to the engine
condition. This improves torque in all the speed ranges as well as increasing fuel economy, and reducing
exhaust emissions.
D For the intake valves, the VVT-iE uses electric motors to control the valve timing. Because the VVT-iE
is actuated by electric motors, it can affect optimal valve timing control even when the engine oil pressure
is low, such as when the engine oil temperature or the engine speed is low. Because this system can control
the valve timing from the time the engine is started, it can set the most retarded timing position to be more
retarded than the starting valve timing. EG
D The exhaust side is VVT-i that uses engine oil pressure to control the valve timing.

Mass Air Flow Meter

(Bank 1, Bank 2)

Throttle Position Sensor

Vehicle Speed Signal

Camshaft Control Motor (Bank 2)

Camshaft Timing OCV* (Bank 2) ECM
Camshaft Position Sensor
Exhaust VVT Sensor (Bank 2)
Intake VVT Sensor (Bank 2)
Engine Coolant Temp. Sensor
Intake VVT Sensor (Bank 1)
Exhaust VVT Sensor (Bank 1)

Crankshaft Position Sensor

Camshaft Timing OCV* (Bank 1)
Camshaft Control Motor (Bank 1)
036EG154TE

*: Oil Control Valve

EG-86 ENGINE – 1UR-FSE ENGINE

Effectiveness of the Dual VVT-i System

Condition Operation Timing/ Objective Effect

Position
TDC
Neutral
IN
Position
Eliminating overlap to
D Stabilized idling
g rpm
p
During Idling EX IN reduce blow back to the
D Better fuel economy
Most intake side.
EX Advanced
BDC 036EG144TE
Position

Retarding the intake

In Low IN Retarded
valve close timing and
Speed Range D Better fuel economy
reducingg pumping
p p g loss.
with EX IN D Improved emission
Increasing overlap and
Light to control
increasing internal
Medium Load EX Retarded
EGR.
036EG141TE

Advancing the intake

In Low to IN Advanced
valve close timing,
Medium
IN reducingg intake air Improved
p torque
q in low
Speed Range EX
blow back to the intake to medium speed range
with
side, and improving
Heavy Load EX Advanced
volumetric efficiency.
036EG142TE

Retarding the intake

IN Retarded
In High valve close timing and
Speed
p Range
g p
improving g volumetric
EX IN Improved output
with efficiency using the
Heavy Load inertia force of the
EX Advanced
intake air.
036EG143TE

Eliminating overlap to
Neutral reduce blow back to the
IN
Position intake side. Fixing valve
At Low EX IN timing g at extremely
y D Stabilized fast idle rpm
p
Temperatures low temperatures and D Better fuel economy
Most
increasing the control
EX Advanced
range as the temperature
036EG144TE Position
rises.

Neutral
IN
Position Controlling valve
D Upon Starting
timingg and fixingg it
D Stopping the EX IN Improved startability
to the optimal timing
Engine Most
for engine start.
EX Advanced
036EG144TE Position
 ENGINE – 1UR-FSE ENGINE EG-87

VVT-iE

1) General
D The VVT-iE consists of the camshaft control actuators that rotate the intake camshafts via a link
mechanism and EDU-integrated the camshaft control motors that operate the link mechanism in
accordance with the signals received from the ECM.
D Based on engine speed, intake air mass, throttle position, vehicle speed, and engine coolant
temperature, the ECM calculates optimal valve timing for all driving conditions. The ECM uses the
calculated valve timing as the target valve timing to control the camshaft control motors. In addition,
the ECM uses signals from the intake VVT sensors and the crankshaft position sensor to detect the
actual valve timing, thus providing feedback control to achieve the target valve timing.
EG
" System Diagram A

ECM
Mass Air Flow Meter
(Bank 1, Bank 2)

Camshaft Control
Throttle Position Sensor Target Valve Timing Motor
(Bank 1, Bank 2)
Camshaft Position Sensor
Feedback
Crankshaft Position
Sensor
Actual Valve Timing
Intake VVT Sensors
(Bank 1, Bank 2)

Engine Coolant
Temperature Sensor Correction

Vehicle Speed Signal Diagnosis

036EG155TE
EG-88 ENGINE – 1UR-FSE ENGINE

2) Camshaft Control Actuator

D The camshaft control actuator consists of a link mechanism that rotates the intake camshaft to the
advance or retard side, and a cycloid reduction unit to reduce the rotational movement of the motor.
D The link mechanism consists of a housing (with sprocket) that is driven by the timing chain, a camshaft
plate that is coupled to the intake camshaft, the links that connect them, and a spiral plate that moves
the links.
D The cycloid reduction unit consists of a housing cover fitted with a stator gear, a carrier that is rotated
by a motor, and a driven gear (which has 1 more tooth than the stator gear) that is engaged to the carrier.
The illustration shows the mechanism of the cycloid reduction unit. When the motor rotates the carrier
by 1 revolution, the driven gear moves in the same direction by only 1 tooth.
D Based on the advance or retard movement of the motor, the camshaft control actuator rotates via the
cycloid reduction unit the spiral plate that is engaged to the driven gear. Then, the links allow the
rotational movement of the spiral plate to rotate the camshaft plate, which changes the intake valve
timing.

" Construction of Camshaft Control Actuator A

Cycloid Reduction Unit

Camshaft Control Motor

Driven Gear
Carrier Intake Camshaft
Housing Cover
(with Stator Gear)

Link Mechanism

Housing (with Sprocket)

Links Camshaft Plate 036EG130TE
Spiral Plate

" Mechanism of Cycloid Reduction Unit A

Driven Gear
Rotates by 1 tooth
Stator Gear of driven gear

Carrier
Carrier rotates 240_

036EG131TE
Carrier rotates 120_ Carrier rotates 360_
 ENGINE – 1UR-FSE ENGINE EG-89

3) Camshaft Control Motor

D The camshaft control motor consists of a motor that operates the camshaft control actuator in the
advance or retard direction, an EDU that controls the rotational condition of the motor, and a Hall IC
type rotational sensor that detects the rotational condition of the motor.
D The motor is a brushless type DC motor that is installed in the engine front cover forward of the
camshaft control actuator. It rotates coaxially with the intake camshaft.
D In accordance with the target valve timing, the ECM transmits the motor rotational speed instruction
signals and the motor rotational direction instruction signals to the EDU. Based on those signals, the
EDU drives the motor to rotate the intake camshaft in the advance or retard direction.
D The EDU always monitors the motor operating condition, and transmits the actual motor rotational
speed signals, the actual motor rotational direction signals, and the operating state signals to the ECM. EG
The ECM uses these signals to diagnose malfunctions.

Brushless Type
DC Motor
EDU

Hall IC Type
Rotational Sensor

036EG132TE
Camshaft Control Motor Cross Section

" System Diagram A

D Motor Rotational Camshaft Control Motor

Speed Instruction
D Motor Rotational
EDT1 Direction Instruction
Rotational Sensor
Actual Motor
EMR1 Rotational Speed

ECM EDU
Actual Motor
EMF1 Rotational Direction

Motor
EMD1 Operating State

036EG156TE
EG-90 ENGINE – 1UR-FSE ENGINE

4) Operation

a. General
D The ECM controls the advance and retard operation by way of the rotational speed difference
between the motor and the camshaft. The ECM maintains the valve timing by rotating the motor at
the same rotational speed as the camshaft.
– To advance, the motor rotational speed becomes faster than the camshaft rotational speed.
– To retard, the motor rotational speed becomes slower than the camshaft rotational speed.
(Depending on the camshaft rotational speed, the motor may rotate counterclockwise.)

" Relationship Between Motor Rotational Speed and Advance and Retard Timing A

: Motor Rotational Speed

: Camshaft Rotational Speed

Most Advanced Position

Valve Timing

Most Retarded Position

Acceleration

Rotational Speed

Deceleration

Advance Hold Retard 036EG157TE

 ENGINE – 1UR-FSE ENGINE EG-91

b. Advance
As the advance signals from the ECM cause the motor to rotate faster than the camshaft, the spiral plate
rotates clockwise via the reduction unit. The rotational movement of the spiral plate moves the link
control pins (which are engaged in the spiral grooves) towards the axial center of the camshaft. As a
result, the links rotate the camshaft plate, which is coupled with the intake camshaft, in the advance
direction.
Spiral Plate
Link Control Pin Rotation Direction

EG

Camshaft Plate
Spiral Grooves Links 036EG133TE

c. Retard
As the retard signals from the ECM cause the motor to rotate slower than the camshaft, the spiral plate
rotates counterclockwise via the reduction unit. The rotational movement of the spiral plate moves the
link control pins (which are engaged in the spiral grooves) outward of the axis of the camshaft. As a
result, the links rotate the camshaft plate, which is coupled with the intake camshaft, in the retard
direction.
Spiral Plate
Link Control Pin Rotation Direction

Camshaft Plate
Spiral Grooves Links 036EG134TE

d. Hold
After the target valve timing has been reached, the ECM rotates the motor at the same rotational speed
as the camshaft. As a result, the link mechanism of the camshaft control actuator becomes locked, thus
holding the camshaft at the valve timing.
EG-92 ENGINE – 1UR-FSE ENGINE

VVT-i

1) General
D The VVT-i consists of the VVT-i controllers that operate by engine oil pressure and the camshaft
timing oil control valves that switches the engine oil pressure passages in accordance with the signals
from the ECM.
D Based on engine speed, intake air mass, throttle position, vehicle speed, and engine coolant
temperature, the ECM calculates optimal valve timing for all driving conditions. The ECM uses the
calculated valve timing as the target valve timing to control the camshaft timing oil control valves.
In addition, the ECM uses signals from the exhaust VVT sensors and the crankshaft position sensor
to detect the actual valve timing, thus providing feedback control to achieve the target valve timing.

" System Diagram A

ECM
Mass Air Flow Meter
(Bank 1, Bank 2)
Duty-cycle
Control Camshaft Timing
Throttle Position Sensor Oil Control Valve
Target Valve Timing (Bank 1, Bank 2)

Camshaft Position Sensor

Feedback
Crankshaft Position
Sensor
Actual Valve Timing
Exhaust VVT Sensors
(Bank 1, Bank 2)

Engine Coolant
Temperature Sensor

Vehicle Speed Signal Correction

036EG158TE
 ENGINE – 1UR-FSE ENGINE EG-93

2) VVT-i controller
D The VVT-i controller consists of a sprocket driven by the timing chain, a housing coupled with the
sprocket, and a vane coupled with the exhaust camshaft.
D The engine oil pressure sent from the advance or retard side path at the exhaust camshaft causes
rotation in the VVT-i controller vane circumferential direction to vary the exhaust valve timing
continuously.
D As the engine stops, the advance assist spring moves the VVT-i controller to the most advanced
position. Then, a lock pin locks the vane to the sprocket, in order to ensure engine startability. After
the engine is started, engine oil pressure acts on the hole in which the lock pin is engaged, to release
the lock.

Sprocket
EG
Lock Pin
Housing

Exhaust Camshaft
Vane

Oil Pressure
Advance Assist Spring
At a Stop In Operation
Lock Pin 036EG135TE

3) Camshaft Timing Oil Control Valve

This camshaft timing oil control valve controls the spool valve using duty cycle control from the ECM.
This allows engine oil pressure to be applied to the VVT-i controller advance or retard side. When the
engine is stopped, the camshaft timing oil control valve is in the most advanced position.

To VVT-i Controller To VVT-i Controller

(Retard Side) (Advance Side)

Sleeve

Spring
Drain Drain Coil Plunger
Oil Pressure
Spool Valve 036EG136TE
EG-94 ENGINE – 1UR-FSE ENGINE

4) Operation

a. Advance
When the camshaft timing oil control valve is positioned as illustrated below by the advance signals
from the ECM, the resultant oil pressure is applied to the timing advance side vane chamber to rotate
the camshaft in the timing advance direction.

Rotation Direction

Camshaft Timing
Oil Control Valve
ECM

Drain IN
Oil Pressure 036EG137TE
Vane

b. Retard
When the camshaft timing oil control valve is positioned as illustrated below by the retard signals from
the ECM, the resultant oil pressure is applied to the timing retard side vane chamber to rotate the
camshaft in the timing retard direction.

Rotation Direction

Camshaft Timing
Oil Control Valve
ECM

IN Drain
Oil Pressure
036EG138TE

Vane

c. Hold
After reaching the target timing, the valve timing is held by keeping the camshaft timing oil control
valve in the neutral position unless the traveling state changes.
This adjusts the valve timing at the desired target position and prevents the engine oil from running out
when it is unnecessary.
 ENGINE – 1UR-FSE ENGINE EG-95

9. ACIS (Acoustic Control Induction System)

General
The ACIS uses a bulkhead to divide the intake manifold into two stages, with an intake air control valve
in the bulkhead being opened and closed to vary the effective length of the intake manifold in accordance
with the engine speed and throttle valve opening angle. This increases the power output in all ranges from
low to high speed.

" System Diagram A

Actuator
EG
Intake Air Control Valve

Throttle Position Sensor

ECM Throttle
Valve

Engine Speed Signal Crankshaft

Position
Throttle Valve Opening Angle Sensor
036EG105TE

Intake Air Control Valve and Actuator

D The intake air control valve is installed in the intake manifold. It opens and closes to provide two effective
lengths of the intake manifold.
D Based on the signals from the ECM, the actuator moves the intake air control valve via a link.

Intake Air Control Valve

Actuator

Link

036EG106TE
EG-96 ENGINE – 1UR-FSE ENGINE

Operation
1) When the Intake Air Control Valve Closes
While the engine is running at low-to-medium speed under heavy load, the ECM causes the actuator to
close the control valve. As a result, the effective length of the intake manifold is lengthened and the intake
efficiency, in the low-to-medium speed range, is improved due to the dynamic effect (inertia) of the
intake air, thereby increasing power output.

Intake Air Control Valve (Close)

Open
Control Valve Close

Throttle
Valve

Throttle Valve Close

Low High
Engine Speed

: Effective Intake Manifold Length 036EG114TE

2) When the Intake Air Control Valve Open

Under any condition except when the engine is running at low-to-medium speed under heavy load, the
ECM causes the actuator to open the control valve. When the control valve is open, the effective length
of the intake air chamber is shortened and peak intake efficiency is shifted to the low-to-high engine
speed range, thus providing greater output at low-to-high engine speeds.

Intake Air Control Valve (Open)

Open

Throttle
Valve
Control Valve Open

Throttle Valve Close

Low High
Engine Speed

: Effective Intake Manifold Length 036EG115TE

 ENGINE – 1UR-FSE ENGINE EG-97

10. Fuel Pump Control

D A fuel cut function is used to stop the fuel pump once when any of the SRS airbags have deployed. In this
system, the airbag deployment signal from the airbag sensor assembly is detected by the ECM, and it turns
OFF the circuit opening relay. After the fuel cut function has been activated, turning the power source from
OFF to ON cancels the fuel cut function, and the engine can be restarted.
D The ECM uses the fuel pump relay and the fuel pump resistor to control the fuel pump speed in accordance
with driving conditions.

" System Diagram A

EG
From From
Front Airbag IG2 Relay EFI Main Relay
Sensor
(RH or LH)
Circuit
Opening
FC Relay
CAN
Front Side Airbag (V Bus)
Airbag Sensor Sensor
(RH or LH) Assembly
ECM
Fuel Fuel
Pump Pump
Relay Resistor
FPR
Rear Side
Airbag Sensor
(RH or LH)
Fuel Pump
Motor

Crankshaft Position Sensor

036EG159TE
EG-98 ENGINE – 1UR-FSE ENGINE

11. Cooling Fan Control System

General
A cooling fan control system is used. To achieve an optimal fan speed in accordance with the engine coolant
temperature, engine speed, vehicle speed, and air conditioning operating conditions, the ECM calculates
an appropriate fan speed and sends signals to the cooling fan ECU via the main body ECU and the front
controller. Upon receiving the signals from the ECM, the cooling fan ECU actuates the fan motors.

" System Diagram A

Engine Coolant From From

Temperature Sensor IG1 Relay Battery

Fan No. 1
Crankshaft Relay
Position Sensor
CAN
(Powertrain
ECT ECU Bus) ECM
Vehicle Speed Signal
Fan Motor
Main
Cooling
A/C ECU CAN Fan ECU
D A/C ON/OFF (V Bus) Fan Motor
Condition Signal Sub
D A/C Refrigerant
Pressure Signal

Main Body
ECU CAN
(MS Bus)
Front
Gateway Controller
Function
036EG160TE
 ENGINE – 1UR-FSE ENGINE EG-99

Operation
D The ECM controls the cooling fan speed in accordance with the value of the engine coolant temperature,
as shown in the graph below. When the engine coolant temperature is higher than a specific value, the
control differs depending on whether the engine speed is at idling and below or more.

More than Idling

At Idling or below
EG
Fan Speed

Engine Coolant Temperature 036EG145S

D The ECM controls the cooling fan speed in accordance with the value of the air conditioning refrigerant
pressure, as shown in the graph below. When the air conditioning refrigerant pressure is higher than a
specific value, the control differs depending on whether the engine speed is at low speeds and below or
more.

Fan Speed

At Low Speeds
or Below

More than
Low Speeds Air Conditioning
Refrigerant Pressure 025EG15TE
EG-100 ENGINE – 1UR-FSE ENGINE

12. Cranking Hold Function

General
D Once the engine switch is pressed, this function continues to operate the starter until the engine has
started, provided that the brake pedal is depressed. This prevents starting failure and the engine from
being cranked after it has started.
D When the ECM detects a start signal from the main body ECU, this system monitors the engine speed
(NE signal) and continues to operate the starter until it has determined that the engine has started.
Furthermore, even if the ECM detects a start signal from the main body ECU, this system will not operate
the starter if the ECM has determined that the engine has already started.

" System Diagram A

PRESS STSW STSW

ACCR ACCR

Engine Switch STR2 STAR

Main Body
ECU From Battery
IG2D

IG2 Relay
Brake Pedal

Starter
Cut
ACC Relay ECM
Relays

Park / Neutral
Position Switch
STA

Starter
Relay

Starter

Engine Coolant
Temperature Sensor
Battery
Crankshaft Position Sensor

036EG161TE
 ENGINE – 1UR-FSE ENGINE EG-101

Operation
D As indicated in the below timing chart, when the ECM detects a STSW signal (start signal) from the main
body ECU, the ECM outputs STAR signal (starter relay drive signal) through the starter cut relay to the
starter relay and actuates the starter. The ECM also outputs ACCR signal (ACC cut request signal) to the
main body ECU. Thus, the main body ECU will not energize the ACC relay.
D After the starter operates and the engine speed becomes higher than approximately 500 rpm, the ECM
determines that the engine has started and stops the output of the STAR signal to the starter relay and the
output of ACCR signal to the main body ECU. Thus, the starter operation stops and the main body ECU
energize the ACC relay.
D If the engine has any failure and does not start, the starter operates as long as its maximum continuous
operation time and stops automatically. The maximum continuous operation time is approximately 5
seconds through 25 seconds depending on the engine coolant temperature condition. When the engine EG
coolant temperature is extremely low, it is approximately 25 seconds and when the engine is warmed up
sufficiently, it is approximately 5 seconds.
D This system cuts off the current that powers the accessories while the engine is cranking to prevent the
accessory illumination from operating intermittently due to the unstable voltage that is associated with
the cranking of the engine.
D This system has following protection features:
– While the engine is running normally, the starter does not operate.
– Even if the driver keeps pressing the engine switch, the ECM stops the output of the STAR and ACCR
signals when the engine speed becomes higher than 1200 rpm. Thus, the starter operation stops and
the main body ECU energize the ACC relay.
– In case the driver keeps pressing the engine switch and the engine does not start, the ECM stops the
output of the STAR and ACCR signals after 30 seconds have elapsed. Thus, the starter operation stops
and the main body ECU energize the ACC relay.
– In case the ECM cannot detect an engine speed signal while the starter is operating, the ECM will
immediately stop the output of the STAR and ACCR signals. Thus, the starter operation stops and the
main body ECU energize the ACC relay.
" Timing Chart A
ON
Start Signal
(STSW)
OFF

Starter Relay ON
Cranking Limit
Drive Signal
(STAR) Approx. 5 to 25 sec.
OFF

ON
ACC Relay (OFF)
(ACC Cut Request OFF
Signal: ACCR)
(ON) Successful
Starting of Engine

Engine Speed
(NE Signal) Failed Starting of
Engine

ECM determines that the engine has started

successfully when the engine speed is
approximately 500 rpm.
036EG162TE
EG-102 ENGINE – 1UR-FSE ENGINE

13. Oil Replacement Reminder (Only for U.S.A. models)

D The oil replacement reminder function of the ECM reminds the driver of the need to replace the engine
oil via the multi-information display in accordance with the vehicle driving distance.
D The ECM calculates the vehicle driving distance based on the signals from the ECT ECU. The ECM sends
a warning display request signal to the meter ECU in accordance with the calculated distance. The meter
ECU will display the warning on the multi-information display based on this signal.
D There are two types of warnings: one is displayed when the vehicle driving distance has reached 4,500
miles or more since the last time the system was reset, and the other is displayed when the driving distance
has reached 5,000 miles or more.
– The “Oil Maintenance Required Soon” warning will appear at 4,500 miles or more. The “Oil
Maintenance Required Soon” warning appears for approximately 15 seconds after the power source is
changed to IG-ON, and then goes off.
– The “Oil Maintenance Required” warning will appear at 5,000 miles or more. The “Oil Maintenance
Required” warning remains on while the power source is IG-ON.
D After the engine oil has been replaced, the accumulated vehicle driving distance is memorized in the ECM
and should be reset through the operation of the RESET switch. At this point, the accumulated vehicle
driving distance is reset to zero.

" System Diagram A

ECM Combination Meter

Multi-information Display
Calculation of
Vehicle Driving
Distance

CAN CAN
(Powertrain (V Bus) : Illuminates
Bus) 4,500 miles or more 5,000 miles or more

Meter ECU

ECT ECU
Vehicle Speed Signal TRIP Switch RESET Switch

036EG164TE
 ENGINE – 1UR-FSE ENGINE EG-103

Service Tip
The accumulated vehicle driving distance is memorized in the ECM and can be reset using the
following procedure.
1) Switch the power source to IG-ON. Then, use the TRIP switch to turn ON the “TRIP A” display
on the multi-information display.
2) Switch the power source to OFF. While pushing the RESET switch, switch the power source to
IG-ON.
3) With the power source in the IG-ON mode, keep holding the RESET switch (for at least five
seconds) with the multi-information display counting down as shown below.
4) When the reset operation is complete, the multi-information display will display “COMPLETE”.
At this time, release the RESET switch. After 6 seconds, the “COMPLETE” display will turn off,
indicating that the resetting is complete. EG

5 seconds before 4 seconds before 3 seconds before

2 seconds before 1 seconds before D Reset complete

D Displays for 6 seconds

TRIP Switch RESET Switch

036EG165TE
EG-104 ENGINE – 1UR-FSE ENGINE

14. Evaporative Emission Control System

General
The evaporative emission control system prevents the fuel vapors that are created in the fuel tank from being
released directly into the atmosphere.
The canister stores the fuel vapors that have been created in the fuel tank.
D The ECM controls the purge VSV in accordance with the driving conditions in order to direct the fuel
vapors into the engine, where they are burned.
D In this system, the ECM checks for evaporative emission leaks and outputs DTC (Diagnostic Trouble
Code) in the event of a malfunction. An evaporative emission leak check consists of an application of
vacuum to the evaporative emissions system and monitoring the system for changes in pressure in order
to detect a leakage.
D This system consists of the purge VSV, canister, refueling valve, canister pump module, and ECM.
D An ORVR (Onboard Refueling Vapor Recovery) function is provided in the refueling valve.
D The canister pressure sensor has been included to the canister pump module.
D A canister filter has been provided on the fresh air line. This canister filter is maintenance-free.
D The following are the typical conditions necessary to enable an evaporative emission leak check:

D Five hours have elapsed after the power source has been turned OFF*.
D Altitude: Below 2400 m (8000 feet)
Typical Enabling D Battery Voltage: 10.5 V or more
Condition D Power Source: OFF
D Engine Coolant Temperature: 4.4 to 35_C (40 to 95_F)
D Intake Air Temperature: 4.4 to 35_C (40 to 95_F)
*: If engine coolant temperature does not drop below 35_C (95_F), this time should be extended to 7 hours.
Even after that, if the temperature is not less than 35_C (95_F), the time should be extended to 9.5 hours.

Service Tip
The pump module performs a fuel evaporative emission leakage check. This check is done
approximately five hours after the power source is turned off. Sound may be heard coming from
underneath the luggage compartment for several minutes. This does not indicate a malfunction.
D Pinpoint pressure test procedure is adopted by pressurizing the fresh air line that runs from the
canister pump module to the air filler neck. For details, refer to the 2007 LEXUS LS460L/LS460
Repair Manual (Pub. No. RM0360U).
 ENGINE – 1UR-FSE ENGINE EG-105

System Diagram

To Intake Manifold
Refueling Valve

Purge VSV
Restrictor
Passage

Canister Pump Module Canister

EG
Fuel Tank
Vent
Valve
Purge Air Line Canister Filter

Fresh Air Line

Leak Detection
ECM Pump

Canister
Pressure Sensor
036EG116TE
Layout of Main Components

Front

Purge VSV

Purge Air Line

Canister Filter

Fresh Air Line Canister Pump Module

D Vent Valve
D Leak Detection Pump
D Canister Pressure Sensor
Canister Refueling Valve

036EG107TE
EG-106 ENGINE – 1UR-FSE ENGINE

Function of Main Components

Component Function
Contains activated charcoal to absorb the fuel vapors that are
Canister
created in the fuel tank.
Controls the flow rate of the fuel vapors from the fuel tank to
the canister when the system is purging or during refueling.
Refueling
Prevents a large amount of vacuum during purge operation or
Valve Restrictor
system monitoring operation from affecting the pressure in the
Passage
fuel tank.
Fresh air goes into the canister and the cleaned drain air goes
Fresh Air Line
out into the atmosphere.
Opens and closes the fresh air line in accordance with the
Vent Valve
signals from the ECM.
Canister Pump Leak Detection Applies vacuum pressure to the evaporative emission system
Module Pump in accordance with the signals from the ECM.
Canister Detects the pressure in the evaporative emission system and
Pressure Sensor sends the signals to the ECM.
Opens in accordance with the signals from the ECM when the
system is purging, in order to send the fuel vapors that were
Purge VSV absorbed by the canister into the intake manifold. In system
monitoring mode, this valve controls the introduction of the
vacuum into the fuel tank.
Prevents dust and debris in the fresh air from entering the
Canister Filter
system.
Controls the canister pump module and the purge VSV in
accordance with the signals from various sensors, in order to
ECM achieve a purge volume that suits the driving conditions. In
addition, the ECM monitors the system for any leakage and
outputs a DTC if a malfunction is found.
 ENGINE – 1UR-FSE ENGINE EG-107

Construction and Operation

1) Refueling Valve
D The refueling valve consists of chamber A, chamber B, and the restrictor passage. A constant
atmospheric pressure is applied to chamber A.
D During refueling, the internal pressure of the fuel tank increases. This pressure causes the refueling
valve to lift up, allowing the fuel vapors to enter the canister.
D The restrictor passage prevents the large amount of vacuum that is created during purge operation or
system monitoring operation from entering the fuel tank, and limits the flow of the fuel vapors from
the fuel tank to the canister. If a large volume of fuel vapors enters the intake manifold, it will affect
the air-fuel ratio control of the engine. Therefore, the role of the restrictor passage is to help prevent EG
this from occurring.

Chamber A

Fresh Air Line

Refueling
Valve (Open)
Chamber B Canister

From To
Fuel Tank Fuel Tank

Internal Pressure Positive Pressure

Restrictor (Fuel Tank Pressure) Negative Pressure
Passage (Intake Manifold Pressure)
030LS05C
During Refueling During Purge Operation or
System Monitoring Operation

2) Fuel Inlet (Fresh Air Inlet)

In accordance with the change of structure of the evaporative emission control system, the location of
the fresh air line inlet has been changed from the air cleaner to the near the fuel inlet. The fresh air from
the atmosphere and drain air cleaned by the canister will go in or out of the system through the passages
shown below.

Fuel Tank Cap

Fresh Air

To Canister

Fuel Inlet Pipe Cleaned Drain Air

228TU119
EG-108 ENGINE – 1UR-FSE ENGINE

3) Canister Pump module

D The canister pump module consists of the vent valve, canister pressure sensor, and leak detection
pump (vacuum pump and pump motor).
D The vent valve switches the passages in accordance with the signals received from the ECM.
D A brushless type DC motor is used for the pump motor.
D A vane type vacuum pump is used.

Vent Valve
Canister Fresh Air
Pressure Sensor

Leak Detection Pump

D Pump Motor
Fresh Air D Vacuum Pump

279EG25

Canister
279EG26

" Simple Diagram A

Canister Pump Module

Vent Valve
(OFF)

Fresh Air
Filter
To Canister
Leak Detection Pump

Canister Pressure Filter

Sensor
Reference Orifice
[0.5 mm, (0.020 in.) Diameter]

036EG117TE
 ENGINE – 1UR-FSE ENGINE EG-109

System Operation

1) Purge Flow Control

When the engine has reached predetermined parameters (closed loop, engine coolant temp. above 80_C
(176_F), etc), stored fuel vapors are purged from the canister whenever the purge VSV is opened by the
ECM.
The ECM will change the duty ratio cycle of the purge VSV, thus controlling purge flow volume. Purge
flow volume is determined by intake manifold pressure and the duty ratio cycle of the purge VSV.
Atmospheric pressure is allowed into the canister to ensure that purge flow is constantly maintained
whenever purge vacuum is applied to the canister.
To Intake Atmosphere
Manifold EG

Purge VSV
(Open)

ECM

036EG118TE

2) ORVR (On-Board Refueling Vapor Recovery)

When the internal pressure of the fuel tank increases during refueling, this pressure causes the diaphragm
in the refueling valve to lift up, allowing the fuel vapors to enter the canister. The air that has had the fuel
vapors removed from it will be discharged through the fresh air line. The vent valve is used to open and
close the fresh air line, and it is always open (even when the engine is stopped) except when the vehicle
is in monitoring mode (the valve will be open as long as the vehicle is not in monitoring mode). If the
vehicle is refueled in system monitoring mode, the ECM will recognize the refueling by way of the
canister pressure sensor, which detects the sudden pressure increase in the fuel tank, and the ECM will
open the vent valve.
Open

Purge VSV
(Closed)

036EG119TE
EG-110 ENGINE – 1UR-FSE ENGINE

3) EVAP Leak Check

a. General
The EVAP leak check operates in accordance with the following timing chart:

" Timing Chart A

Purge ON (Open)
VSV OFF (Close)

Vent ON
Valve OFF (Vent)
Leak ON
Detection
OFF
Pump

Atmospheric Pressure

System
Pressure

0.02 in. Pressure

1) 2) 3) 4) 5) 6)
060XA19C

Order Operation Description Time

The ECM turns the vent valve OFF (vent) and measures
Atmospheric Pressure
1) EVAP system pressure to memorize the atmospheric —
Measurement
pressure.
The leak detection pump creates negative pressure
0.02 in. Leak (vacuum) through a 0.02 in. orifice and the pressure is
2) 20 sec.
Pressure Measurement measured. The ECM determines this as the 0.02 in. leak
pressure.
The leak detection pump creates negative pressure
(vacuum) in the EVAP system and the EVAP system
pressure is measured. If the stabilized pressure is larger
Within
3) EVAP Leak Check than the 0.02 in. leak pressure, ECM determines that the
15 min.
EVAP system has a leak.
If the EVAP pressure does not stabilize within 15
minutes, the ECM cancels EVAP monitor.
The ECM opens the purge VSV and measures the EVAP
4) Purge VSV Monitor pressure increase. If the increase is large, the ECM 10 sec.
interprets this as normal.
The leak detection pump creates negative pressure
Repeat 0.02 in. Leak (vacuum) through the 0.02 in. orifice and the pressure is
5) 20 sec.
Pressure Measurement measured. The ECM determines this as the 0.02 in. leak
pressure.
The ECM measures the atmospheric pressure and
6) Final Check —
records the monitor result.
 ENGINE – 1UR-FSE ENGINE EG-111

b. Atmospheric Pressure Measurement

1) When the power source is turned OFF, the purge VSV and the vent valve are turned OFF. Therefore,
atmospheric pressure is introduced into the canister.
2) The ECM measures the atmospheric pressure based on the signals provided by the canister pressure
sensor.
3) If the measurement value is out of standards, the ECM actuates the leak detection pump in order to
monitor the changes in the pressure.

Atmosphere
EG

Purge VSV
(OFF)

Canister Pump Module

Vent Valve
(OFF)

ECM Leak Detection

Pump (OFF)

Canister Pressure
Sensor
036EG120TE

ON (Open)
Purge VSV
OFF (Close)

ON
Vent Valve OFF (Vent)

Leak Detection ON
Pump OFF

Atmospheric Pressure

System Pressure

Atmospheric Pressure Measurement

036EG125TE
EG-112 ENGINE – 1UR-FSE ENGINE

c. 0.02 in. Leak Pressure Measurement

1) The vent valve remains off, and the ECM introduces atmospheric pressure into the canister and
actuates the leak detection pump in order to create a negative pressure.
2) At this time, the pressure will not decrease beyond a 0.02 in. pressure due to the atmospheric pressure
that enters through a 0.02 in. diameter reference orifice.
3) The ECM compares the logic value and this pressure, and stores it as a 0.02 in. leak pressure in its
memory.
4) If the measurement value is below the standard, the ECM will determine that the reference orifice
is clogged and store DTC P043E in its memory.
5) If the measurement value is above the standard, the ECM will determine that a high flow rate pressure
is passing through the reference orifice and store DTC P043F, P2401 and P2402 in its memory.

Atmosphere

Purge VSV
(OFF)

Canister Pump Module

Vent Valve
(OFF)

ECM Leak Detection

Pump (ON)

Canister Pressure
Sensor
Reference Orifice
036EG121TE

ON (Open)
Purge VSV
OFF (Close)

ON
Vent Valve
OFF (Vent)

Leak Detection ON
Pump OFF

Atmospheric Pressure

System Pressure

0.02 in. Pressure

0.02 in. Leak Pressure Measurement 036EG126TE

 ENGINE – 1UR-FSE ENGINE EG-113

d. EVAP Leak Check

1) While actuating the leak detection pump, the ECM turns ON the vent valve in order to introduce a
vacuum into the canister.
2) When the pressure in the system stabilizes, the ECM compares this pressure and the 0.02 in. pressure
in order to check for a leakage.
3) If the detection value is below the 0.02 in. pressure, the ECM determines that there is no leakage.
4) If the detection value is above the 0.02 in. pressure and near atmospheric pressure, the ECM
determines that there is a gross leakage (large hole) and stores DTC P0455 in its memory.
5) If the detection value is above the 0.02 in. pressure, the ECM determines that there is a small leakage
and stores DTC P0456 in its memory.

Atmosphere EG

Purge VSV
(OFF)

Canister Pump Module

Vacuum

Vent Valve
(ON)

Leak Detection
ECM Pump (ON)

Canister Pressure
Sensor Reference Orifice
036EG122TE

ON (Open)
Purge VSV
ON (Close)

ON
Vent Valve
OFF (Vent)

ON
Leak Detection
OFF
Pump

P0455
Atmospheric Pressure

System Pressure
P0456

0.02 in. Pressure

Normal

EVAP Leak Check 036EG127TE

EG-114 ENGINE – 1UR-FSE ENGINE

e. Purge VSV Monitor

1) After completing an EVAP leak check, the ECM turns ON (open) the purge VSV with the leak
detection pump actuated, and introduces the atmospheric pressure from the intake manifold to the
canister.
2) If the pressure change at this time is within the normal range, the ECM determines the condition to
be normal.
3) If the pressure is out of the normal range, the ECM will stop the purge VSV monitor and store DTC
P0441 in its memory.
Atmosphere

Purge VSV
(ON)

Canister Pump Module

Vent Valve
(ON)

ECM Leak Detection

Pump (ON)

Canister Pressure
Sensor Reference Orifice
036EG123TE

ON (Open)
Purge VSV
OFF (Close)

ON
Vent Valve
OFF (Vent)

Leak Detection ON
Pump OFF

Atmospheric Pressure
Normal
System Pressure

0.02 in. Pressure

P0441

Purge VSV Monitor

036EG128TE
 ENGINE – 1UR-FSE ENGINE EG-115

f. Repeat 0.02 in. Leak Pressure Measurement

1) While the ECM operates the leak detection pump, the purge VSV and vent valve turns off and a repeat
0.02 in. leak pressure measurement is performed.
2) The ECM compares the measured pressure with the pressure during EVAP leak check.
3) If the pressure during the EVAP leak check is below the measured value, the ECM determines that
there is no leakage.
4) If the pressure during the EVAP leak check is above the measured value, the ECM determines that
there is a small leak and stores DTC P0456 in its memory.

Atmosphere EG

Purge VSV
(OFF)

Canister Pump Module

Vent Valve
(OFF)

ECM Leak Detection

Pump (ON)

Canister Pressure
Sensor Reference Orific
036EG124TE

ON (Open)
Purge VSV
OFF (Close)

ON
Vent Valve
OFF (Vent)

ON
Leak Detection
OFF
Pump

Atmospheric Pressure

System Pressure

P0456
0.02 in. Pressure
Normal

Repeat 0.02 in. Leak Pressure Measurement

036EG129TE
EG-116 ENGINE – 1UR-FSE ENGINE

15. Diagnosis
D When the ECM detects a malfunction, the ECM makes a diagnosis and memorizes the failed section.
Furthermore, the MIL (Malfunction Indicator Lamp) in the combination meter illuminates or blinks to
inform the driver.
D The ECM will also store the DTC (Diagnostic Trouble Code) of the malfunctions. The DTC can be
accessed by using the hand-held tester or techstream.
D For details, refer to the 2007 LEXUS LS460L/LS460 Repair Manual (Pub. No. RM0360U).

Service Tip
D The ECM of the ’07 LS460L/460 uses the CAN protocol for diagnostic communication.
Therefore, When using a hand-held tester, a dedicated adapter [CAN VIM (Vehicle Interface
Module)] must be connected between the DLC3 and the hand-held tester. For details, refer to the
2007 LEXUS LS460L/LS460 Repair Manual (Pub. No. RM0360U).
D To clear the DTC that is stored in the ECM, use the hand-held tester or techstream, disconnect the
battery terminal or remove the EFI MAIN fuse and ETCS fuse for 1 minute or longer.

16. Fail-Safe

General
When a malfunction is detected at any of the sensors, there is a possibility of an engine or other malfunction
occurring if the ECM were to continue to control the engine control system in the normal way. To prevent
such a problem, the fail-safe function of the ECM either relies on the data stored in memory to allow the
engine control system to continue operating, or stops the engine if a hazard is anticipated. For details, refer
to the 2007 LEXUS LS460L/LS460 Repair Manual (Pub. No. RM0360U).
 ENGINE – 1UR-FSE ENGINE EG-117

Fail-safe Operation due to Accelerator Pedal Position Sensor Trouble

D The accelerator pedal position sensor comprises two (Main, Sub) sensor circuits.
D If a malfunction occurs in either of the sensor circuits, the ECM detects the abnormal signal voltage
difference between these two sensor circuits and switches into a fail-safe mode. In this fail-safe mode,
the remaining circuit is used to calculate the accelerator pedal opening, in order to operate the vehicle
under failsafe mode control.

ECM

EG
Accelerator Pedal
Position Sensor Return Spring
Open

Main Sub
Main
M
Sub
Throttle Throttle
Throttle Valve
Position Control
Sensor Motor
Throttle Body
D13N08

D If both circuits malfunction, the ECM detects the abnormal signal voltage from these two sensor circuits
and discontinues the throttle control. At this time, the vehicle can be driven within its idling range.

ECM

Accelerator Pedal Return Spring

Position Sensor Close

Main Sub
Main
M
Sub
Throttle Throttle
Throttle Valve
Position Control
Sensor Motor
Throttle Body

D13N09
EG-118 ENGINE – 1UR-FSE ENGINE

Fail-safe Operation due to Throttle Position Sensor Trouble

D The throttle position sensor comprises two (Main, Sub) sensor circuits.
D If a malfunction occurs in either of the sensor circuits, the ECM detects the abnormal signal voltage
difference between these two sensor circuits, cuts off the current to the throttle control motor, and
switches to a fail-safe mode.
D Then, the force of the return spring causes the throttle valve to return and stay at the prescribed base
opening position. At this time, the vehicle can be driven in the fail-safe mode while the engine output
is regulated through control of the fuel injection and ignition timing in accordance with the accelerator
pedal position.
D The same control as above is effected if the ECM detects a malfunction in the throttle control motor
system.

Injectors ECM Ignition Coils

Accelerator Pedal Return Spring

Position Sensor Open

Main Sub
Main
M
Sub
Throttle Throttle
Throttle Valve Control
Position
Sensor Motor
Throttle Body

D13N10