2007 INFINITI QX56 wheel

TROUBLE DIAGNOSES FOR SYMPTOMS
BRC-51
< SERVICE INFORMATION >[VDC/TCS/ABS]
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3.CHECK CONNECTOR AND BRAKING PERFORMANCE
1. Disable ABS by disconnecting ABS actuator and electric unit (control unit) connector.
2. Drive vehicle and check brake operation.
NOTE:
• Stopping distance may be longer than vehicles without ABS when road condition is slippery.
• Driving the vehicle with the ABS actuator and electric unit (control unit) disconnected may induce DTCs
in electrical control units using CAN communication. After the inspection, clear all DTCs. Refer to LAN-
7.
OK or NG
OK >> GO TO 4.
NG >> Perform Basic Inspection. Refer to BRC-22, "
Basic Inspection".
4.CHECK WHEEL SENSORS
Check the following.
• Wheel sensor mounting for looseness
• Wheel sensors for physical damage
• Wheel sensor connectors for terminal damage or loose connections
OK or NG
OK >> Check ABS actuator and electric unit (control unit) connector terminals for deformation, discon-
nection, looseness or damage. Reconnect ABS actuator and electric unit (control unit) harness
connector. Then retest.
NG >> Repair or replace as necessary.
Long Stopping DistanceINFOID:0000000003532804
INSPECTION PROCEDURE
1.CHECK BASE BRAKING SYSTEM PERFORMANCE
1. Disable ABS by disconnecting ABS actuator and electric unit (control unit) connector.
2. Drive vehicle and check brake operation.
NOTE:
• Stopping distance may be longer than vehicles without ABS when road condition is slippery.
• Driving the vehicle with the ABS actuator and electric unit (control unit) disconnected may induce DTCs
in electrical control units using CAN communication. After the inspection, clear all DTCs. Refer to LAN-
7.
OK or NG
OK >> Go to BRC-50, "ABS Works Frequently".
NG >> Perform Basic Inspection. Refer to BRC-22, "
Basic Inspection".
ABS Does Not WorkINFOID:0000000003532805
CAUTION:
The ABS does not operate when the vehicle speed is 10 km/h (6 MPH) or less.
INSPECTION PROCEDURE
1.CHECK WARNING LAMP ACTIVATION
Turn ignition switch ON and check for warning lamp activation.
• Warning lamp should activate for approximately 2 seconds after turning the ignition switch ON.
OK or NG
OK >> Carry out self-diagnosis. Refer to BRC-26, "CONSULT-II Function (ABS)".
NG >> Go to BRC-22, "
Basic Inspection".
Pedal Vibration or ABS Operation NoiseINFOID:0000000003532806
NOTE:
During ABS activation, pedal vibration may be felt and a noise may be heard. This is normal and does not indi-
cate a malfunction.
INSPECTION PROCEDURE

BRC-54
< SERVICE INFORMATION >[VDC/TCS/ABS]
ON-VEHICLE SERVICE
ON-VEHICLE SERVICE
Adjustment of Steering Angle Sensor Neutral PositionINFOID:0000000003532809
After removing/installing or replacing ABS actuator and electric unit (control unit), steering angle sensor, steer-
ing and suspension components which affect wheel alignment or after adjusting wheel alignment, be sure to
adjust neutral position of steering angle sensor before running vehicle.
NOTE:
Adjustment of steering angle sensor neutral position requires CONSULT-II.
1. Stop vehicle with front wheels in straight-ahead position.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data
link connector on vehicle, and turn ignition switch ON (do not
start engine).
3. Touch “START (NISSAN BASED VHCL)”, “ABS”, “WORK SUP-
PORT” and “ST ANGLE SENSOR ADJUSTMENT” on CON-
SULT-II screen in this order.
4. Touch “START”.
CAUTION:
Do not touch steering wheel while adjusting steering angle
sensor.
5. After approximately 10 seconds, touch “END”. (After approxi-
mately 60 seconds, it ends automatically.)
6. Turn ignition switch OFF, then turn it ON again.
7. Run vehicle with front wheels in straight-ahead position, then
stop.
8. Select “DATA MONITOR”, “SELECTION FROM MENU”, and
“STR ANGLE SIG” on CONSULT-II screen. Then check that
“STR ANGLE SIG” is within 0±3.5 deg. If value is more than specification, repeat steps 1 to 5.
9. Erase memory of ABS actuator and electric unit (control unit) and ECM.
10. Turn ignition switch to OFF.
Calibration of Decel G SensorINFOID:0000000003532810
After removing/installing or replacing ABS actuator and electric unit (control unit), yaw rate/side/decel G sen-
sor, steering and suspension components which affect wheel alignment or after adjusting wheel alignment, be
sure to calibrate the decel G sensor before running vehicle.
NOTE:
Calibration of decel G sensor requires CONSULT-II.
1. Stop vehicle with front wheels in straight-ahead position.
CAUTION:
• The work should be done on a level area with an unloaded vehicle.
• Keep all the tires inflated to the correct pressures. Adjust the tire pressure to the specified pres-
sure value.
2. Connect CONSULT-II with CONSULT-II CONVERTER to data link connector on vehicle, and turn ignition
switch ON (do not start engine).
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
3. Touch “START (NISSAN BASED VHCL)”, "ABS", "WORK SUPPORT" and "DECEL G SEN CALIBRA-
TION" on CONSULT-II screen in this order. Refer to BRC-26, "
CONSULT-II Function (ABS)".
BBIA0369E
WFIA0239E

ON-VEHICLE SERVICE
BRC-55
< SERVICE INFORMATION >[VDC/TCS/ABS]
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4. Touch "START".
CAUTION:
Set vehicle as shown in the display.
5. After approximately 10 seconds, touch "END". (After approxi-
mately 60 seconds, it ends automatically.)
6. Turn ignition switch OFF, then turn it ON again.
CAUTION:
Be sure to carry out above operation
7. Run vehicle with front wheels in straight-ahead position, then
stop.
8. Select "DATA MONITOR", "SELECTION FROM MENU", and
"DECEL G SEN" on CONSULT-II screen. Then check that "DECEL G SEN" is within ±0.08G. If value is
more than specification, repeat steps 3 to 7.
9. Erase memory of ABS actuator and electric unit (control unit) and ECM.
10. Turn ignition switch to OFF.
SFIA1162E

BRC-56
< SERVICE INFORMATION >[VDC/TCS/ABS]
WHEEL SENSOR
WHEEL SENSOR
Removal and InstallationINFOID:0000000003532811
REMOVAL
1. Remove wheel sensor bolt.
• When removing the front wheel sensor, first remove the disc rotor to gain access to the front wheel sen-
sor bolt. Refer to BR-19, "
Removal and Installation of Brake Caliper and Disc Rotor" .
• When removing the rear wheel sensor, first remove the rear hub and bearing assembly to gain access to
the rear wheel sensor bolt. Refer to FA X - 5 , "
Removal and Installation" .
2. Pull out the sensor, being careful to turn it as little as possible.
CAUTION:
• Do not pull on the sensor harness.
3. Disconnect wheel sensor harness electrical connector, then remove harness from attaching points.
INSTALLATION
Installation is in the reverse order of removal. Tighten wheel sensor bolt to specification.
CAUTION:
Installation should be performed while paying attention to the following.
• Inspect wheel sensor O-ring, replace sensor assembly if damaged.
• Before installing wheel sensor, make sure no foreign materials (such as iron fragments) are adhered
to the pick-up part of the sensor, to the inside of the sensor hole or on the rotor mating surface.
• Apply a coat of suitable grease to the wheel sensor O-ring and hole. Refer to MA-10
.
WFIA0376E

SENSOR ROTOR
BRC-57
< SERVICE INFORMATION >[VDC/TCS/ABS]
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SENSOR ROTOR
Removal and InstallationINFOID:0000000003532812
NOTE:
The wheel sensor rotors are built into the wheel hubs and are not removable. If damaged, replace wheel hub
and bearing assembly. Refer to FAX-5, "
Removal and Installation" (front), RAX-5, "Removal and Installation"
(rear).

OVERHEATING CAUSE ANALYSIS
CO-7
< SERVICE INFORMATION >
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Except cool-
ing system
parts mal-
function— Overload on engineAbusive drivingHigh engine rpm under no
load
Driving in low gear for ex-
tended time
Driving at extremely high
speed
Powertrain system malfunc-
tion
— Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flowBlocked bumper —
— Blocked radiator grilleInstalled car brassiere
Mud contamination or paper
clogging
Blocked radiator —
Blocked condenser
Blocked air flow
Installed large fog lamp Symptom Check items

ENGINE CONTROL SYSTEM
EC-25
< SERVICE INFORMATION >
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*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*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 both the crankshaft position sensor 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
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
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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
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
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
PBIB3020E

ENGINE CONTROL SYSTEM
EC-27
< SERVICE INFORMATION >
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This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speed.
Electronic Ignition (EI) SystemINFOID:0000000003531587
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 8 - 7 - 3 - 6 - 5 - 4 -2
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor signal. Comput-
ing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised by the ECM according to the other data stored in
the ECM.
• At starting
• During warm-up
•At idle
• At low battery voltage
• During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Fuel Cut Control (at No Load and High Engine Speed)INFOID:0000000003531588
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
2
Piston position
Ignition timing
controlPower transistor Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor
Vehicle speed*1
Sensor Input signal to ECM ECM function Actuator
Park/neutral position (PNP) switch Neutral position
Fuel cut control Fuel injector Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Wheel sensor Vehicle speed*