2011 INFINITI QX56 power steering

PRECAUTIONSBRC-7
< PRECAUTION > [WITH VDC]
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and tires installed on the vehicle are the specified si ze and parts. Brake performance and controllability may
be negatively affected when other parts than the specified are installed.
 Brake stopping distance may become longer and steering stability may be negatively affected, when tires in
different size and combination or other parts than the specified are used.
 When a radio (including wiring), antenna and antenna lead line are located near ABS actuator and electric
unit (control unit), a malfunction or improper operation ma y occur for the control of VDC function, TCS func-
tion, ABS function, EBD function, hill start assist func tion or brake limited slip differential (BLSD) function.
 When the following items are replaced by other parts than genuine parts or modified, ABS warning lamp, brake warning lamp and VDC warning lamp may turn ON, and the control may not operate normally for VDC
function, TCS function, ABS function, EB D function, hill start assist function or brake limited slip differential
(BLSD) function.
- Suspension component parts (shock absorber, spring, bushing and others)
- Tire and wheel (other than the specified size)
- Brake component parts (brake pad, disc rotor, brake caliper and others)
- Engine component parts (ECM, muffler and others)
- Body reinforcement component parts (rollover bar, tower bar and others)
 When suspension, tire and brake component parts are excessively worn or deteriorated and the vehicle is
driven, ABS warning lamp, brake warning lamp and VDC warning lamp may tu\
rn ON, and the control may
not operate normally for VDC function, TCS function, ABS function, EBD function, hill start assist function or
brake limited slip differential (BLSD) function.
 ABS warning lamp, brake warning lamp and VDC warning lamp may turn ON, when only front wheel or rear wheel is rotated using a free roller. This is not a ma lfunction, because it is caused by wheel speed difference
between wheel that is rotated and wheel that is not rota ted. In this case, perform self-diagnosis, check self-
diagnosis results, and erase memory.
 When power supply voltage is not normal, ABS warning lamp, brake warning lamp and VDC warning lamp
turn ON. ABS actuator and electric unit (control unit) st ops control for VDC function, TCS function, ABS func-
tion, EBD function, hill start assist function or brake limited slip differential (BLSD) function. Ordinary brake
operates. After power supply returns to normal, ABS warning lamp, brake warning lamp and VDC warning
lamp turn OFF. The control becomes operative for VD C function, TCS function, ABS function, EBD function,
hill start assist function or brake li mited slip differential (BLSD) function.
 VDC warning lamp may turn ON and VDC function or TCS function may not normally operate, when driving
on a special road the is extremely slanted (bank in a circ uit course). This is not a malfunction if the status
returns to normal for VDC function or TCS function after the engine is started again. In this case, perform
self-diagnosis, check self-diagnosis results, and erase memory.
 A malfunction in yaw rate/side/decel G sensor syste m may be detected when the vehicle sharply turns dur-
ing a spin turn, acceleration turn or drift driving while VDC function or TCS function are OFF (VDC OFF
switch is pressed and VDC OFF indicator lamp is in ON st atus). This is not a malfunction if the status returns
to normal for VDC function or TCS function after the engine is started again. In this case, perform self-diag-
nosis, check self-diagnosis results, and erase memory
Precaution for Harness RepairINFOID:0000000006222558
 Solder the repair part, and wrap it with tape. [Twisted wire fray must be 110 mm (4.33 in) or less.]
SKIB8766E
Revision: 2010 May2011 QX56

COMPONENT PARTSBRC-15
< SYSTEM DESCRIPTION > [WITH VDC]
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 Downsize and weight reduction is aimed. IC for detection portion and magnet for sensor rotor are adopted.
 Power supply is supplied to detection portion so that magnetic field
line is read. Magnetic field that is detected is converted to current
signal.
 When sensor rotor rotates, magnetic field changes. Magnetic field
change is converted to current signals (rectangular wave) and is
transmitted to ABS actuator and electric unit (control unit). Change
of magnetic field is pr oportional to wheel speed.
Stop Lamp SwitchINFOID:0000000006222563
Detects the operation status of brake pedal and transmits converted electric signal to ABS actuator and elec-
tric unit (control unit).
Steering Angle SensorINFOID:0000000006222564
Detects the following information and transmits steering angle signal to ABS actuator and electric unit (control
unit) via CAN communication.
 Steering wheel rotation amount
 Steering wheel rotation angular velocity
 Steering wheel rotation direction
Yaw Rate/Side/Decel G sensorINFOID:0000000006222565
Calculates the following information that affects the v ehicle and transmits a signal to ABS actuator and electric
unit (control unit) via communication lines.
 Vehicle rotation angular velocity (yaw rate signal)
 Vehicle lateral acceleration (side G signal) / longitudinal acceleration (decel G signal)
Brake Fluid Level SwitchINFOID:0000000006222566
Detects the brake fluid level in reservoir tank and trans mits converted electric signal from ABS actuator and
electric unit (control unit), when brake fluid level is the specified level or less.
Parking Brake SwitchINFOID:0000000006222567
Detects the operation status of parking brake switch and transmits converted electric signal from combination
meter to ABS actuator and electric unit (control unit).
VDC OFF SwitchINFOID:0000000006222568
 VDC OFF switch is integrated in SNOW MODE / TOW MODE / VDC OFF switch assembly (2WD models) or
4WD switch assembly (4WD models).
 The operation of the VDC OFF switch enables the arbi trary switching of the VDC function between stop sta-
tus and standby status. The status of the function is indicated by the VDC OFF indicator lamp. (ON: Non-
operational status, OFF: Standby status)
- VDC function NOTE:
Brake limited slip differentia l (BLSD) control operates.
- TCS function
 VDC OFF indicator lamp turns OFF (standby status) when the engine is started again after it is stopped once while VDC OFF indicator lamp is ON (non-operational status).
JPFIC0131GB
Revision: 2010 May2011 QX56

SYSTEMBRC-17
< SYSTEM DESCRIPTION > [WITH VDC]
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O P*1: Communication line between yaw rate/side/decal G s ensor and ABS actuator and electric unit (control unit)
*2: Models with 4WD system
VALVE OPERATION
Each valve is operated and fluid pressure of brake caliper is controlled.
When Ordinary Brake is Applied
NOTE:
Control pressure sensor is applied to model s with Advanced Driver Assistance System.
TCMMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN
communication.
 Shift position signal
 Current gear position signal
Transfer control unit
*2Mainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN
communication.
 Current 4WD mode signal
Steering angle sensor Mainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN
communication.
 Steering angle sensor signal
Combination meter Mainly receives the following signals from ABS actuator and electric unit (control unit) via CAN
communication.
 ABS warning lamp signal
 Brake warning lamp signal
 VDC warning lamp signal
 VDC OFF indicator lamp
Component Signal description
Name Not activated When depressing brake pedal
Cut valve 1 Power supply is not supplied (open) Power supply is not supplied (open)
Cut valve 2 Power supply is not supplied (open) Power supply is not supplied (open)
Suction valve 1 Power supply is not supplied (close) Power supply is not supplied (close)
Suction valve 2 Power supply is not supplied (close) Power supply is not supplied (close)
JPFIC0150GB
Revision: 2010 May2011 QX56

BRC-68
< DTC/CIRCUIT DIAGNOSIS >[WITH VDC]
C1101, C1102, C1103,
C1104 WHEEL SENSOR
DTC/CIRCUIT DIAGNOSIS
C1101, C1102, C1103, C1104 WHEEL SENSOR
DTC LogicINFOID:0000000006222592
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK DTC DETECTION
With CONSULT-III.
1. Turn the ignition switch OFF to ON.
2. Perform self-diagnosis for “ABS”.
Is DTC
“C1101”, “C1102”, “C1103” or “C1104” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-68, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222593
CAUTION:
Never check between wheel sensor harness connector terminals.
1.CHECK WHEEL SENSOR HARNESS
1. Turn the ignition switch OFF.
2. Disconnect ABS actuator and electric unit (control unit) harness connector.
3. Disconnect wheel sensor harness connector.
4. Check continuity between ABS actuator and electr ic unit (control unit) harness connector and wheel sen-
sor harness connector. (Check continuity when steering wheel is steered to RH and LH, or center harness
in wheel housing is moved.)
Measurement connector and termi nal for power supply circuit
Measurement connector and te rminal for signal circuit
DTC Display Item Malfunction detected condition Possible causes
C1101 RR RH SENSOR-1 When an open circuit is detected in rear RH wheel
sensor circuit.
 Harness or connector
 Wheel sensor
 ABS actuator and electric unit (control unit)
C1102 RR LH SENSOR-1
When an open circuit is detected in rear LH wheel
sensor circuit.
C1103 FR RH SENSOR-1 When an open circuit is detected in front RH wheel
sensor circuit.
C1104 FR LH SENSOR-1 When an open circuit is detected in front LH wheel
sensor circuit.
ABS actuator and electric unit
(control unit) Wheel sensor
Continuity
Connector Terminal Connector Terminal
E36 20 E22 (Front LH wheel)
1 Existed
33 E39 (Front RH wheel)
22 C10 (Rear LH wheel)
35 C11 (Rear RH wheel)
ABS actuator and electric unit (control unit) Wheel sensor
Continuity
Connector Terminal Connector Terminal
E36 34 E22 (Front LH wheel)
2 Existed
19 E39 (Front RH wheel)
36 C10 (Rear LH wheel)
21 C11 (Rear RH wheel)
Revision: 2010 May2011 QX56

C1115 WHEEL SENSORBRC-77
< DTC/CIRCUIT DIAGNOSIS > [WITH VDC]
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C1115 WHEEL SENSOR
DTC LogicINFOID:0000000006222601
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK DTC DETECTION
With CONSULT-III.
1. Start engine and drive vehicle at approx. 30 km/h (19 MPH) or more for approx. 1 minute.
2. Perform self-diagnosis for “ABS”.
Is DTC
“C 111 5” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-77, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222602
CAUTION:
For wheel sensor, never check between terminals.
1.CHECK TIRE
1. Turn the ignition switch OFF.
2. Check tire air pressure, wear and size. Refer to WT-69, "
Tire Air Pressure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Adjust air pressure. Or replace tire. Refer to WT-69, "
Tire Air Pressure".
2.CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) POWER SUPPLY SYSTEM
Check ABS actuator and electric unit (cont rol unit) power supply system. Refer to BRC-113, "
Diagnosis Proce-
dure".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK WHEEL SENSOR HARNESS
1. Disconnect ABS actuator and electric unit (control unit) harness connector.
2. Disconnect wheel sensor harness connector.
3. Check continuity between ABS actuator and electr ic unit (control unit) harness connector and wheel sen-
sor harness connector. (Check continuity when steering wheel is steered to RH and LH, or center harness
in wheel housing is moved.)
Measurement connector and termi nal for power supply circuit
DTC Display Item Malfunction detected condition Possible causes
C 111 5 ABS SENSOR
[ABNORMAL SIGNAL] When difference in wheel speed between any wheel
and others is detected during the vehicle is driven,
because of installation of other tires than specified.  Harness or connector
 Wheel sensor
 Sensor rotor
 ABS actuator and electric unit
(control unit)
ABS actuator and electric unit (control unit) Wheel sensor Continuity
Connector Terminal Connector Terminal
E36 20 E22 (Front LH wheel)
1 Existed
33 E39 (Front RH wheel)
22 C10 (Rear LH wheel)
35 C11 (Rear RH wheel)
Revision: 2010 May2011 QX56

C1143 STEERING ANGLE SENSORBRC-97
< DTC/CIRCUIT DIAGNOSIS > [WITH VDC]
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C1143 STEERING ANGLE SENSOR
DTC LogicINFOID:0000000006222619
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK DTC DETECTION
With CONSULT-III.
1. Turn the ignition switch OFF to ON.
2. Perform self-diagnosis for “ABS”.
Is DTC
“C1143” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-97, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222620
1.CHECK STEERING ANGLE SE NSOR MOUNTING CONDITION
Check steering angle sensor mounting condition. Refer to SR-14, "
Exploded View".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK STEERING ANGLE SENSOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect steering angle sensor harness connector.
3. Check voltage between steering angle sensor harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start engine.
5. Check voltage between steering angle sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.CHECK STEERING ANGLE SENSOR POWER SUPPLY CIRCUIT
1. Turn the ignition switch OFF.
2. Check 10A fuse (#7).
DTC Display Item Malfunction detected condition Possible causes
C1143 ST ANG SEN CIRCUIT When a malfunction is detected in steering angle sen-
sor.  Harness or connector
 Steering angle sensor
 ABS actuator and electric unit
(control unit)
Fuse
 Ignition power supply system
 CAN communication line
Steering angle sensor — Voltage
Connector Terminal
M30 4 Ground Approx. 0 V
Steering angle sensor — Voltage
Connector Terminal
M30 4 Ground Battery voltage
Revision: 2010 May2011 QX56

BRC-98
< DTC/CIRCUIT DIAGNOSIS >[WITH VDC]
C1143 STEERING ANGLE SENSOR
3. Disconnect fuse block (J/B) harness connector.
4. Check continuity between steering angle sensor
harness connector and fuse block (J/B) harness connec-
tor.
5. Check continuity between steering angle sensor harness connector and ground.
Is the inspection result normal?
YES >> Perform trouble diagnosis for ignition power supply. Refer to PG-89, "Wiring Diagram - IGNITION
POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
4.CHECK STEERING ANGL E SENSOR GROUND CIRCUIT
1. Turn the ignition switch OFF.
2. Check continuity between steering angle sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.CHECK TERMINAL
 Check steering angle sensor pin terminals for damage or loose connection with harness connector.
 Check fuse block (J/B) pin terminals for damage or loose connection with harness connector.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair or replace error-detected parts.
6.CHECK CAN COMMUNICATION LINE
Check “STRG BRANCH LINE CIRCUIT”. Refer to LAN-81, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> Replace ABS actuator and electr ic unit (control unit). Refer to BRC-137, "Removal and Installa-
tion".
NO >> Repair or replace error-detected parts. Refer to BRC-7, "
Precaution for Harness Repair".
Steering angle sensor Fuse block (J/B)
Continuity
Connector Terminal Connector Terminal
M30 4 M1 2A Existed
Steering angle sensor —Continuity
Connector Terminal
M30 4 Ground Not existed
Steering angle sensor —Continuity
Connector Terminal
M30 1 Ground Existed
Revision: 2010 May2011 QX56

CCS-3
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ICC SENSOR : Diagnosis Procedure .................
..
112
C1A24 NP RANGE ...........................................113
DTC Logic ........................................................... ..113
Diagnosis Procedure .............................................113
C1A26 ECD MODE MALFUNCTION ...............115
DTC Logic ........................................................... ..115
Diagnosis Procedure .............................................115
C1A27 ECD POWER SUPPLY CIRCUIT .........116
DTC Logic ........................................................... ..116
Diagnosis Procedure .............................................116
C1A2A ICC SENSOR POWER SUPPLY CIR-
CUIT ..................................................................
117
DTC Logic ........................................................... ..117
Diagnosis Procedure .............................................117
C1A33 CAN TRANSMISSION ERROR ...........118
DTC Logic ........................................................... ..118
Diagnosis Procedure .............................................118
C1A34 COMMAND ERROR .............................119
DTC Logic ........................................................... ..119
Diagnosis Procedure .............................................119
C1A35 ACCELERATOR PEDAL ACTUATOR ..120
DTC Logic ........................................................... ..120
Diagnosis Procedure .............................................120
C1A36 ACCELERATOR PEDAL ACTUATOR
CAN COMM ......................................................
121
DTC Logic ........................................................... ..121
Diagnosis Procedure .............................................121
C1A37 ACCELERATOR PEDAL ACTUATOR
CAN 2 ...............................................................
122
DTC Logic ........................................................... ..122
Diagnosis Procedure .............................................122
C1A38 ACCELERATOR PEDAL ACTUATOR
CAN 1 ...............................................................
123
DTC Logic ........................................................... ..123
Diagnosis Procedure .............................................123
C1A39 STEERING ANGLE SENSOR ..............124
ADAS CONTROL UNIT ......................................... ..124
ADAS CONTROL UNIT : DTC Logic ....................124
ADAS CONTROL UNIT : Diagnosis Procedure ....124
ICC SENSOR ......................................................... ..124
ICC SENSOR : DTC Logic ....................................124
ICC SENSOR : Diagnosis Procedure ...................125
C1A40 SYSTEM SWITCH CIRCUIT ................126
DTC Logic ........................................................... ..126
Diagnosis Procedure .............................................126
Component Inspection (IBA OFF Switch) .............127
C1A50 ADAS CONTROL UNIT .......................128
DTC Logic ............................................................ ..128
Diagnosis Procedure .............................................128
C1F01 ACCELERATOR PEDAL ACTUATOR .129
DTC Logic ............................................................ ..129
Diagnosis Procedure .............................................129
C1F02 ACCELERATOR PEDAL ACTUATOR .130
DTC Logic ............................................................ ..130
Diagnosis Procedure .............................................130
C1F05 ACCELERATOR PEDAL ACTUATOR
POWER SUPPLY CIRCUIT ............................
131
DTC Logic ..............................................................131
Diagnosis Procedure .............................................131
U0104 ADAS CAN 1 .......................................132
DTC Logic ............................................................ ..132
Diagnosis Procedure .............................................132
U0121 VDC CAN 2 ..........................................133
ADAS CONTROL UNIT ......................................... ..133
ADAS CONTROL UNIT : DTC Logic .....................133
ADAS CONTROL UNIT : Diagnosis Procedure ....133
ICC SENSOR ......................................................... ..133
ICC SENSOR : DTC Logic ....................................133
ICC SENSOR : Diagnosis Procedure ....................134
U0126 STRG SEN CAN 1 ...............................135
ADAS CONTROL UNIT ......................................... ..135
ADAS CONTROL UNIT : DTC Logic .....................135
ADAS CONTROL UNIT : Diagnosis Procedure ....135
ICC SENSOR ......................................................... ..135
ICC SENSOR : DTC Logic ....................................135
ICC SENSOR : Diagnosis Procedure ....................136
U0235 ICC SENSOR CAN 1 ...........................137
DTC Logic ............................................................ ..137
Diagnosis Procedure .............................................137
U0401 ECM CAN 1 .........................................138
DTC Logic ..............................................................138
Diagnosis Procedure .............................................138
U0402 TCM CAN 1 ..........................................139
DTC Logic ............................................................ ..139
Diagnosis Procedure .............................................139
U0405 ADAS CAN 2 .......................................140
DTC Logic ............................................................ ..140
Diagnosis Procedure .............................................140
U0415 VDC CAN 1 ..........................................141
ADAS CONTROL UNIT ......................................... ..141
ADAS CONTROL UNIT : DTC Logic .....................141
ADAS CONTROL UNIT : Diagnosis Procedure ....141
ICC SENSOR ......................................................... ..141
Revision: 2010 May2011 QX56