2008 INFINITI QX56 brake

BRC-48
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1120, C1122, C1124,
C1126 IN ABS SOL
C1120, C1122, C1124, C1126 IN ABS SOL
DescriptionINFOID:0000000001686292
The solenoid valve increases, holds or decreases the flui d pressure of each brake caliper according to the sig-
nals transmitted by the ABS actuator and electric unit (control unit).
DTC LogicINFOID:0000000001686293
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-48, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686294
INSPECTION PROCEDURE
1.CHECK CONNECTOR
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, re\
pair or replace terminal.
4. Reconnect connectors and then perform the self-diagnosis. Refer to BRC-24, "
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 SOLENOID, VDC SWITCH-OVER VALVE A ND ACTUATOR RELAY POWER SUPPLY CIRCUIT
DTCDisplay item Malfunction detected condition Possible cause
C1120 FR LH IN ABS SOL When the control unit detects a malfunction in the front
LH inlet solenoid circuit.
• ABS actuator and electric unit (control unit)
C1122 FR RH IN ABS SOL
When the control unit detects a malfunction in the front
RH inlet solenoid circuit.
C1124 RR LH IN ABS SOL When the control unit detects a malfunction in the rear LH
inlet solenoid circuit.
C1126 RR RH IN ABS SOL When the control unit detects a malfunction in the rear
RH inlet solenoid circuit.
Self-diagnosis results
FR LH IN ABS SOL
FR RH IN ABS SOL RR LH IN ABS SOL
RR RH IN ABS SOL
Revision: March 2010 2008 QX56

C1121, C1123, C1125, C1127 OUT ABS SOL
BRC-51
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
C
D
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G H
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J
K L
M A
B
BRC
N
O P
C1121, C1123, C1125, C1127 OUT ABS SOL
DescriptionINFOID:0000000001686297
The solenoid valve increases, holds or decreases the flui d pressure of each brake caliper according to the sig-
nals transmitted by the ABS actuator and electric unit (control unit).
DTC LogicINFOID:0000000001686298
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-51, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001691150
INSPECTION PROCEDURE
1.CHECK CONNECTOR
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-24, "
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
DTCDisplay item Malfunction detected condition Possible cause
C1121 FR LH OUT ABS SOL When the control unit detects a malfunction in the front
LH outlet solenoid circuit.
• ABS actuator and electric unit (control unit)
C1123 FR RH OUT ABS SOL
When the control unit detects a malfunction in the front
RH outlet solenoid circuit.
C1125 RR LH OUT ABS SOL When the control unit detects a malfunction in the rear LH
outlet solenoid circuit.
C1127 RR RH OUT ABS SOL When the control unit detects a malfunction in the rear
RH outlet solenoid circuit.
Self-diagnosis results
FR LH OUT ABS SOL
FR RH OUT ABS SOL RR LH OUT ABS SOL
RR RH OUT ABS SOL
Revision: March 2010 2008 QX56

BRC-58
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1142 PRESS SENSOR
C1142 PRESS SENSOR
DescriptionINFOID:0000000001686311
The front and rear pressure sensors convert the brake flui
d pressure to an electric signal and transmit it to the
ABS actuator and electric unit (control unit).
DTC LogicINFOID:0000000001686312
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-58, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686313
FRONT PRESSURE SENSOR INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the front pressure sensor connector E31 and ABS actuator and electric unit (control unit) con-
nector E125 and inspect the terminals for def ormation, 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) harness connector E125 (A) and front pres-
sure sensor harness connector E31 (B).
2. Measure the continuity between the ABS actuator and electric unit (control unit) harness connector E125
(A) and body ground.
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: March 2010 2008 QX56

C1142 PRESS SENSORBRC-59
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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G H
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M A
B
BRC
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Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
3.FRONT PRESSURE SENSOR INSPECTION
1. Reconnect the front pressure sensor and ABS actuator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if the status of “PRESS SENSOR” is normal.
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace the front pressure sensor.
REAR PRESSURE SENSOR INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the rear pressure sensor connector E32 and ABS actuator and electric unit (control unit) con-
nector E125 and inspect the terminals for defo rmation, 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) harness connector E125 (A) and rear pressure
sensor harness connector E32 (B).
2. Measure the continuity between t he ABS actuator and electric unit (control unit) harness connector E125
(A) and body ground.
ABS actuator and electric unit (control
unit) —Continuity
Connector Terminal
A: E125 18
Ground No
19
20
Condition PRESS SENSOR
(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
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) —Con tin uit y
Connector Terminal
A: E125 21
Ground No
22
23
AWFIA0022ZZ
Revision: March 2010 2008 QX56

BRC-60
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1142 PRESS SENSOR
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
3.REAR PRESSURE SENSOR INSPECTION
1. Reconnect the rear pressure sensor and ABS act uator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if t he status of “PRESS SEN2” is normal.
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace the rear pressure sensor.
Component InspectionINFOID:0000000001686314
1.CHECK DATA MONITOR
On “DATA MONITOR”, select “PRESS SENSOR” and “PRESS SEN2” and check the brake fluid pressure.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-58, "
Diagnosis Procedure".
Special Repair RequirementINFOID:0000000001691156
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
Condition 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
Condition PRESS SENSOR
and 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: March 2010 2008 QX56

BRC-64
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1155 BRAKE FLUID LEVEL SWITCH
C1155 BRAKE FLUID LEVEL SWITCH
DescriptionINFOID:0000000001686321
The brake fluid level switch converts the brake fluid level to an electric signal and transmits it to the ABS actu-
ator and electric unit (control unit).
DTC LogicINFOID:0000000001686322
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-64, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686323
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Disconnect ABS actuator and electric unit (control unit) connector E125 and brake fluid level switch con- nector E21.
2. Check the terminals for deformati on, disconnection, looseness or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair or replace as necessary.
2.CHECK HARNESS BETWEEN BRAKE FLUID LEVE L SWITCH AND ABS ACTUATOR AND ELECTRIC
UNIT (CONTROL UNIT)
1. Check continuity between ABS actuator and electric unit (control
unit) harness connector E125 (A) and brake fluid level switch
harness connector E21 (B).
2. Check continuity between ABS ac tuator and electric unit (control
unit) harness connector E125 (A) and ground.
Is the inspection result normal?
DTC Display item Malfunction detected condition Possible cause
C1155 BR FLUID LEVEL LOW Brake fluid level is low or communication line between
the ABS actuator and electric unit (control unit) and brake
fluid level switch is open or shorted. • Harness or connector
• Brake fluid level switch
•Brake fluid level
Self-diagnosis results
BR FLUID LEVEL LOW
ABS actuator and electric unit (control unit) Brake fluid level switch
Continuity
Connector Terminal Connector Terminal
A: E125 8B: E21 1Yes
ABS actuator and electric unit (control unit) —Continuity
Connector Terminal
A: E125 8Ground No
AWFIA0025ZZ
Revision: March 2010 2008 QX56

C1155 BRAKE FLUID LEVEL SWITCHBRC-65
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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BRC
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YES >> GO TO 3
NO >> Repair or replace malfunctioning components.
3.CHECK BRAKE FLUID LEVEL SWITCH GROUND
Check continuity between brake fluid level switch harness connector
E21 and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Repair or replace malfunctioning components.
4.CHECK BRAKE FLUID LEVEL SWITCH
Check continuity between brake fluid level switch terminals.
Is the inspection result normal?
YES >> Perform self-diagnosis again. If the same results appear, replace ABS actuator and electric unit (control unit). Refer to BRC-116, "
Removal and
Installation".
NO >> Replace brake fluid level switch.
Component InspectionINFOID:0000000001686324
1.CHECK BRAKE FLUID LEVEL SWITCH
1. Turn ignition switch OFF.
2. Disconnect brake fluid level switch connector.
3. Check continuity between brake fluid level switch terminals.
Is the inspection result normal?
YES >> Inspection End
NO >> Replace brake fluid level switch.
Special Repair RequirementINFOID:0000000001691158
1.ADJUSTMENT OF STEERING AN GLE 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".
Brake fluid level switch
—Continuity
Connector Terminal
E21 2Ground Yes
AWFIA0026ZZ
Brake fluid level switch
ConditionContinuity
Te r m i n a l
1 − 2 When brake fluid is full in the reser-
voir tank.
No
When brake fluid is empty in the
reservoir tank. Ye s
ALFIA0026ZZ
Brake fluid level switch
ConditionContinuity
Te r m i n a l
1 − 2 When brake fluid is full in the reser-
voir tank.
No
When brake fluid is empty in the
reservoir tank. Ye s
ALFIA0026ZZ
Revision: March 2010
2008 QX56

BRC-66
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1155 BRAKE FLUID LEVEL SWITCH
>> 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
Revision: March 2010 2008 QX56