2010 INFINITI QX56 ABS

C1140 ACTUATOR RLYBRC-55
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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C1140 ACTUATOR RLY
DescriptionINFOID:0000000005148013
Activates or deactivates each solenoid valve according to the signals transmitted by the ABS actuator and
electric unit (control unit).
DTC LogicINFOID:0000000005148014
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-55, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000005194932
Regarding Wiring Diagram information, refer to BRC-92, "Wiring Diagram - BRAKE CONTROL SYSTEM -".
1.CONNECTOR INSPECTION
1. Turn ignition switch OFF.
2. Disconnect ABS actuator and electric unit (control unit) connector.
3. Check terminal for deformation, disconnection, looseness, and so on. If any malfunction is found, repair or replace terminal.
4. Reconnect connectors and then perform the self-diagnosis. Refer to BRC-23, "
CONSULT-III Function
(ABS)".
Is any item indicated on the self-diagnosis display?
YES >> GO TO 2
NO >> Poor connection of connector terminal. Repair or replace connector.
2.CHECK SOLENOID, VDC SWITCH-OVER VALVE A ND ACTUATOR RELAY POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ABS actuator and electric unit (control unit) connec- tor.
3. Check voltage between ABS actuator and electric unit (control unit) connector E125 terminal 32 and ground.
Is the inspection result normal?
YES >> GO TO 3
DTC Display item Malfunction detected condition Possible cause
C1140 ACTUATOR RLY ABS actuator relay or circuit malfunction. • Harness or connector
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
ACTUATOR RLY
ABS actuator and electric unit (control unit) —Volt a ge
Connector Terminal
E125 32Ground Battery voltage
AWFIA0018ZZ
Revision: April 20092010 QX56

BRC-56
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1140 ACTUATOR RLY
NO >> Repair or replace malfunctioning components.
3.CHECK SOLENOID, VDC SWITCH-OVER VALV
E AND ACTUATOR RELAY GROUND CIRCUIT
Check continuity between ABS actuator and electric unit (control
unit) connector E125 terminals 16, 47 and ground.
Is the inspection result normal?
YES >> Replace ABS actuator and electric unit (control unit). Refer to BRC-116, "
Removal and Installation".
NO >> Repair or replace malfunctioning components.
Component InspectionINFOID:0000000005194929
1.CHECK ACTIVE TEST
1. On “ACTIVE TEST”, select “ABS MOTOR”.
2. Touch “On” and “Off” on screen. Make sure motor re lay and actuator relay operates as shown in table
below.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-55, "
Diagnosis Procedure".
Special Repair RequirementINFOID:0000000005194917
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replac ing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
ABS actuator and electric unit (control unit) —Continuity
Connector Terminal
E125 16, 47GroundYes
AWFIA0016ZZ
Operation OnOff
MOTOR RELAY OnOff
ACTUATOR RLY OnOn
Revision: April 20092010 QX56

C1142 PRESS SENSORBRC-57
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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C1142 PRESS SENSOR
DescriptionINFOID:0000000005148018
The front and rear pressure sensors c onvert the brake fluid pressure to an electric signal and transmit it to the
ABS actuator and electric unit (control unit).
DTC LogicINFOID:0000000005148019
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-57, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000005148020
Regarding Wiring Diagram information, refer to BRC-92, "Wiring Diagram - BRAKE CONTROL SYSTEM -".
FRONT PRESSURE SENSOR
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the front pressure sensor connector and AB S actuator and electric unit (control unit) connec-
tor and inspect the terminals for deformation, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.
2.FRONT PRESSURE SENSOR CIRCUIT INSPECTION
1. Measure the continuity betw een the ABS actuator and electric
unit (control unit) connector E125 (A) and front pressure sensor
connector E31 (B).
DTC Display item Malfunction detected condition Possible cause
C1142 PRESS SEN CIRCUIT Pressure sensor signal line is open or shorted, or pres-
sure sensor is malfunctioning. • Harness or connector
• Pressure sensor
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
PRESS SEN CIRCUIT
ABS actuator and electric unit (control unit) Front pressure sensor
Continuity
Connector Terminal Connector Terminal
A: E125 18
B: E31 3
Ye s
19 1
20 2
AWFIA0021ZZ
Revision: April 20092010 QX56

BRC-58
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1142 PRESS SENSOR
2. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 (A) and
body ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
3.FRONT PRESSURE SENSOR INSPECTION
1. Connect the front pressure sensor and ABS act uator and electric unit (control unit) connectors.
2. Perform the front pressure sensor component inspection. Refer to BRC-59, "
Component Inspection".
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace the front pressure sensor.
REAR PRESSURE SENSOR
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the rear pressure sensor connector and AB S actuator and electric unit (control unit) connector
and inspect the terminals for deformation, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.
2.REAR PRESSURE SENSOR CIRCUIT INSPECTION
1. Measure the continuity betw een the ABS actuator and electric
unit (control unit) connector E125 (A) and rear pressure sensor
connector E32 (B).
2. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 (A) and body ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
ABS actuator and electric unit (control unit) —Contin u it y
Connector Terminal
A: E125 18
Ground No
19
20
ABS actuator and electric unit
(control unit) Rear pressure sensor
Continuity
Connector Terminal Connector Terminal
A: E125 21
B: E32 1
Ye s
22 3
23 2
ABS actuator and electric unit (control unit) —Contin u it y
Connector Terminal
A: E125 21
Ground No
22
23
AWFIA0022ZZ
Revision: April 20092010 QX56

C1142 PRESS SENSORBRC-59
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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3.REAR PRESSURE SENSOR INSPECTION
1. Connect the rear pressure sens or and ABS actuator and electric unit (control unit) connectors.
2. Perform the rear pressure sensor component inspection. Refer to BRC-59, "
Component Inspection".
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace the rear pressure sensor.
Component InspectionINFOID:0000000005148021
1.CHECK DATA MONITOR
On “DATA MONITOR”, select “PRESS SENSOR” or “PRESS SEN2” and check the brake fluid pressure.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-57, "
Diagnosis Procedure".
Condition PRESS SENSOR or PRESS SEN2
(DATA MONITOR)
With ignition switch turned ON and brake pedal released. Approx. 0 bar
With ignition switch turned ON and brake pedal depressed. Positive value
Revision: April 20092010 QX56

BRC-60
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1143, C1144 STEERING ANGLE SENSOR
C1143, C1144 STEERING ANGLE SENSOR
DescriptionINFOID:0000000005148023
The steering angle sensor detects the rotation amount,
angular velocity and direction of the steering wheel,
and transmits the data to the ABS actuator and el ectric unit (control unit) via CAN communication.
DTC LogicINFOID:0000000005148024
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-60, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000005148025
Regarding Wiring Diagram information, refer to BRC-92, "Wiring Diagram - BRAKE CONTROL SYSTEM -".
1.CONNECTOR INSPECTION
1. Turn ignition switch OFF.
2. Disconnect ABS actuator and electric unit (control unit) connector.
3. Disconnect steering angle sensor connector.
4. Check terminal for deformation, disconnection, looseness, and so on. If any malfunction is found, repair or replace terminal.
5. Reconnect connectors and then perform the self-diagnosis. Refer to BRC-23, "
CONSULT-III Function
(ABS)".
Is any item indicated on the self-diagnosis display?
YES >> GO TO 2
NO >> Poor connection of connector term inal. Repair or replace connector.
2.CHECK STEERING ANGLE SENSOR HARNESS
1. Turn ignition switch OFF.
2. Disconnect steering angle sensor connector.
DTC Display item Malfunction detected condition Possible cause
C1143 ST ANG SEN CIRCUIT Neutral position of steering angle sensor is dislocated, or
the steering angle sensor is malfunctioning. • Harness or connector
• Steering angle sensor
• ABS actuator and electric unit
(control unit)
C1144 ST ANG SEN SIGNAL Neutral position of steering angle sensor is not finished.
Self-diagnosis results
ST ANG SEN CIRCUIT ST ANG SEN SIGNAL
Revision: April 20092010 QX56

C1143, C1144 STEERING ANGLE SENSORBRC-61
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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3. Check continuity between steering angle sensor connector M17 terminal 2 and ground.
4. Turn ignition switch ON.
5. Check voltage between steering angle sensor connector M17 terminal 3 and ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace malfunctioning components.
3.CHECK DATA MONITOR
1. Connect the steering angle sensor connector and ABS ac tuator and electric unit (control unit) connector.
2. Perform the steering angle sensor component inspection. Refer to BRC-61, "
Component Inspection".
Is the inspection result normal?
YES >> Replace ABS actuator and electric unit (control unit). Refer to BRC-116, "Removal and Installa-
tion".
NO >> Replace steering angle sensor and adjust neutra l position of steering angle sensor. Refer to BRC-
118, "Removal and Installation".
Component InspectionINFOID:0000000005148026
1.CHECK DATA MONITOR
Select “STR ANGLE SIG” in “DATA MONITOR” and check steering angle sensor signal.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-60, "
Diagnosis Procedure".
Special Repair RequirementINFOID:0000000005194918
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
Steering angle sensor —Continuity
Connector Terminal
M17 2Ground Yes
WFIA0399E
Steering angle sensor
—Voltage
Connector Terminal
M17 3Ground Battery voltage
AWFIA0023ZZ
Steering condition STR ANGLE SIG (DATA MONITOR)
Driving straight ±2.5 °
Turn 90 ° to right Approx. +90 °
Turn 90 ° to left Approx. −90 °
Revision: April 20092010 QX56

BRC-62
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1143, C1144 STEERING ANGLE SENSOR
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replac ing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
Revision: April 20092010 QX56