2007 INFINITI M35 steering system

BRC-32
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
For Fast and Accurate DiagnosisNFS000QJ
PRECAUTIONS FOR DIAGNOSIS

Before performing diagnosis, always read General Information (GI) to confirm general precautions. Refer
to GI-4, "
General Precautions" .

If steering angle sensor, steering system parts, suspension system parts, ABS actuator and electric unit
(control unit) or tires have been replaced, or if wheel alignment has been adjusted, be sure to adjust neu-
tral position of steering angle sensor before driving. Refer to BRC-6, "
Adjustment of Steering Angle Sen-
sor Neutral Position" .

After diagnosis is finished, be sure to erase memory. Refer to BRC-24, "ERASE MEMORY" .

When checking continuity and voltage between unit, be sure to check for disconnection, looseness, bend,
or collapse of connector terminals. If any malfunction is found, repair or replace connector terminals.

For intermittent symptoms, possible cause is malfunction in harness, harness connector, or terminals.
Move harness, harness connector, and terminals to check for poor connections.

If a circuit tester is used for the check, be careful not to forcibly extend any connector terminal.

The following symptoms may be caused by normal operations.
Symptom Symptom description Result
Motor operation soundThis is sound of motor inside VDC actuator. Slight sound may occur
during VDC, TCS, and ABS operation.
Normal
Just after engine starts, the motor operating sound may be heard.
This is a normal condition of the system operation check.
System operation check soundWhen engine starts, slight “click” sound may be heard from engine
room. This is normal and is part of system operation check.Normal
VDC/TCS operation
(SLIP indicator lamp ON)TCS may activate momentarily if wheel speed changes when driving
over location where friction varies, when downshifting, or when fully
depressing accelerator pedal.Normal
Cancel the VDC/TCS
function for the inspec-
tion on a chassis dyna-
mometer. When checking speed meter etc. With a 2-wheel-drive chassis dyna-
mometer, vehicle speed is not increased by pressing down on the
accelerator.
ABS operation
(Longer stopping distance)On roads with low friction, such as snowy roads or gravel roads, vehi-
cles with ABS may require a longer stopping distance. Therefore,
when driving on such roads, avoid overconfidence and keep speed
sufficiently low.Normal
Insufficient feeling of accelerationDepending on road conditions, driver may feel that feeling of acceler-
ation is insufficient. This is because traction control, which controls
engine and brakes to achieve optimal traction, has the highest priority
(for safety). As a result, there may be times when acceleration is
slightly less than usual for the same accelerator pedal operation.Normal

TROUBLE DIAGNOSIS FOR SYSTEM
BRC-35
[VDC/TCS/ABS]
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BRC
Revision: 2007 April2007 M35/M45
5. CHECK WHEEL SENSOR HARNESS
1. Turn ignition switch OFF and disconnect malfunctioning wheel
sensor connector E41(FR-RH), E59(FR-LH), B466(RR-RH),
B467(RR-LH) and ABS actuator and electric unit (control unit)
connector E30.
2. Check continuity between terminals. (Also check continuity
when steering wheel is turned right and left and when sensor
harness inside the wheel house is moved.)
OK or NG
OK >> GO TO 6.
NG >>

Repair or replace malfunctioning components.

Perform the self-diagnosis, and make sure that the result shows “NO DTC IS DETECTED”.
6. CHECK WHEEL SENSOR POWER SUPPLY CIRCUIT
1. Disconnect malfunctioning wheel sensor connector.
2. Turn ignition switch ON and check voltage between wheel sen-
sor harness connector power supply terminal and ground.
OK or NG
OK >> Replace wheel sensor.
NG >> Replace ABS actuator and electric unit (control unit).
SFIA3030E
Power supply circuit Signal circuit Ground circuit
WheelABS actuator
and electric unit
(control unit)Wheel sensorABS actuator
and electric unit
(control unit)Wheel sensorABS actuator
and electric unit
(control unit)
(signal)Ground
Front RH 9 1 10 2 9, 10
— Front LH 26 1 5 2 26, 5
Rear RH 7 1 29 2 7, 29
Rear LH 6 1 27 2 6, 27
Power supply circuit : Continuity should exist.
Signal circuit : Continuity should exist.
Ground circuit : Continuity should not exist.
Wheel Wheel sensor Ground Voltage
Front RH
1—8 V or more Front LH
Rear RH
Rear LH
SFIA3341E

TROUBLE DIAGNOSIS FOR SYSTEM
BRC-41
[VDC/TCS/ABS]
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BRC
Revision: 2007 April2007 M35/M45
4. CHECK STOP LAMP SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch connector E124 and ABS actuator and electric unit (control unit) connector
E30.
3. Check continuity between stop lamp switch harness connector and ABS actuator and electric unit (control
unit) harness connector.
OK or NG
OK >> GO TO 5.
NG >> Open or short in harness between stop lamp switch and ABS actuator and electric unit (control
unit). Repair or replace applied harness.
5. CHECK PRESSURE SENSOR
1. Connect ABS actuator and electric unit (control unit) connector.
2. Perform “DATA MONITOR” of the “PRESS SENSOR” to check if the status is normal.
OK or NG
OK >> INSPECTION END
NG >> If the pressure sensor is damaged or malfunctioning, replace the ABS actuator and electric unit
(control unit).
Steering Angle Sensor CircuitNFS000QS
INSPECTION PROCEDURE
1. CHECK SELF-DIAGNOSIS RESULTS
Check self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> GO TO 2.
NO >> INSPECTION END
2. CHECK CONNECTOR
1. Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector E30,
check terminal for deformation, disconnection, looseness, and so on. If any malfunction is found, repair or
replace terminal.
2. Reconnect connector and perform self-diagnosis.
OK or NG
OK >> INSPECTION END
NG >> GO TO 3.
ABS actuator and electric unit (control unit) Stop lamp switch Continuity
30 4 Yes
Condition Data monitor display
When brake pedal is depressed.−40 to 300 bar
When brake pedal is released. Approx. 0 bar
Self-diagnosis results
ST ANG SEN CIRCUIT

BRC-42
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: 2007 April2007 M35/M45
3. CHECK STEERING ANGLE SENSOR HARNESS
1. Check CAN communication system. Refer to BRC-48, "
CAN Communication Circuit" .
2. Turn ignition switch OFF and disconnect steering angle sensor connector.
3. Check continuity between steering angle sensor harness con-
nector M47 terminal 2 and ground.
4. Turn ignition switch ON and check voltage between steering
angle sensor harness connector M47 terminal 3 and ground.
OK or NG
OK >> GO TO 4.
NG >>

Repair or replace malfunctioning components.

Perform the self-diagnosis, and make sure that the
result shows “NO DTC IS DETECTED”.
4. CHECK DATA MONITOR
1. Turn ignition switch OFF and connect the steering angle sensor connector and ABS actuator and electric
unit (control unit) connector.
2. Select “STR ANGLE SIG” in “DATA MONITOR” and check steering angle sensor signal.
OK or NG
OK >> Perform self-diagnosis.
NG >>

Replace spiral cable (steering angle sensor) and adjust neutral position of steering angle sen-
sor. Refer to BRC-6, "
Adjustment of Steering Angle Sensor Neutral Position" .

Perform the self-diagnosis, and make sure that the result shows “NO DTC IS DETECTED”.
Steering angle sensor Ground Continuity
2—Yes
SFIA2970E
Steering angle sensor Ground Voltage
3—Battery voltage
(Approx. 12 V)
SFIA2971E
Steering condition STR ANGLE SIG (DATA MONITOR)
Driving straight – 2.5 ° to + 2.5 °
Turn 90° to right Approx. + 90 °
Turn 90° to left Approx. – 90 °

ENGINE CONTROL SYSTEM
EC-31
[VQ35DE]
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EC
Revision: 2007 April2007 M35/M45
Multiport Fuel Injection (MFI) SystemNBS004S3
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from the crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.


During warm-up

When starting the engine

During acceleration

Hot-engine operation

When selector lever is changed from N to D

High-load, high-speed operation


During deceleration

During high engine speed operation
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
3
Knock sensor Engine knocking condition
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit)
VDC/TCS operation command*
2
Air conditioner switch
Air conditioner operation*2
Wheel sensor
Vehicle speed*2

AIR CONDITIONING CUT CONTROL
EC-35
[VQ35DE]
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EC
Revision: 2007 April2007 M35/M45
AIR CONDITIONING CUT CONTROLPFP:23710
Input/Output Signal ChartNBS004S6
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionNBS004S7
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.

When the accelerator pedal is fully depressed.

When cranking the engine.

At high engine speeds.

When the engine coolant temperature becomes excessively high.

When operating power steering during low engine speed or low vehicle speed.

When engine speed is excessively low.

When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch
Air conditioner ON signal*
1
Air conditioner
cut controlAir conditioner relay Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor
Vehicle speed*
1

EC-36
[VQ35DE]
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
Revision: 2007 April2007 M35/M45
AUTOMATIC SPEED CONTROL DEVICE (ASCD)PFP:18930
System DescriptionNBS004S8
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric throttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE lamp and SET lamp in combination meter. If any malfunc-
tion occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE lamp in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET lamp in combination meter illuminates.)
ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exist, cruise operation will be canceled.

CANCEL switch is pressed

More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)

Brake pedal is depressed

Selector lever is changed to N, P, R position

Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed

VDC/TCS system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.

Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to the normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.

Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
Sensor Input signal to ECM ECM function Actuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator Stop lamp switch Brake pedal operation
ASCD steering switch ASCD steering switch operation
Park/Neutral position (PNP)
switchGear position
Wheel sensor Vehicle speed*
TCM Powertrain revolution*

EC-86
[VQ35DE]
BASIC SERVICE PROCEDURE
Revision: 2007 April2007 M35/M45
Accelerator Pedal Released Position LearningNBS004SU
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Repeat step 2 and 3 for 4 times.
Throttle Valve Closed Position LearningNBS004SV
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningNBS004SW
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:

Each time electric throttle control actuator or ECM is replaced.

Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.

Battery voltage: More than 12.9V (At idle)

Engine coolant temperature: 70 - 105°C (158 - 221°F)

PNP switch: ON

Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine
is started the headlamp will not be illuminated.

Steering wheel: Neutral (Straight-ahead position)

Vehicle speed: Stopped

Transmission: Warmed-up
–With CONSULT-II: Drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indi-
cates less than 0.9V.
–Without CONSULT-II: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-86, "Accelerator Pedal Released Position Learning" .
2. Perform EC-86, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.