2008 INFINITI QX56 brake

BRC-88
< ECU DIAGNOSIS >[VDC/TCS/ABS]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
SIDE G-SENSOR Transverse G detected by side G sensorVehicle stopped
Approx. 0 m/s
2
Vehicle turning rightNegative value
(m/s2)
Vehicle turning left Positive value
(m/s
2)
STR ANGLE SIG Steering angle detected by steering angle
sensor Straight-ahead
Approx. 0±2.5°
Steering wheel turned –720 to +720°
PRESS SENSOR Brake fluid pressure detected by front pres-
sure sensor With ignition switch turned ON and brake
pedal released
Approx. 0 bar
With ignition switch turned ON and brake
pedal depressed –40 to 300 bar
ENGINE SPEED With engine running With engine stopped
0 rpm
Engine running Almost in accor-
dance with tachome-
ter display
FLUID LEV SW Brake fluid level switch signal status When brake fluid level switch ON
ON
When brake fluid level switch OFF OFF
FR RH IN SOL Operation status of each solenoid valve Actuator (solenoid valve) is active (“AC-
TIVE TEST” with CONSULT-III) or actua-
tor relay is inactive (in fail-safe mode)
ON
When the actuator (solenoid valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
FR RH OUT SOL Operation status of each solenoid valve Actuator (solenoid valve) is active (“AC-
TIVE TEST” with CONSULT-III) or actua-
tor relay is inactive (in fail-safe mode)
ON
When the actuator (solenoid valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
FR LH IN SOL Operation status of each solenoid valve Actuator (solenoid valve) is active (“AC-
TIVE TEST” with CONSULT-III) or actua-
tor relay is inactive (in fail-safe mode)
ON
When the actuator (solenoid valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
FR LH OUT SOL Operation status of each solenoid valve Actuator (solenoid valve) is active (“AC-
TIVE TEST” with CONSULT-III) or actua-
tor relay is inactive (in fail-safe mode)
ON
When the actuator (solenoid valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
RR RH IN SOL Operation status of each solenoid valve Actuator (solenoid valve) is active (“AC-
TIVE TEST” with CONSULT-III) or actua-
tor relay is inactive (in fail-safe mode)
ON
When the actuator (solenoid valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
Monitor item
Display content Data monitor
Condition Reference value in
normal operation
Revision: March 2010 2008 QX56

BRC-90
< ECU DIAGNOSIS >[VDC/TCS/ABS]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
TCS FAIL SIG TCS fail-safe signalIn TCS fail-safe ON
TCS is normal
OFF
VDC FAIL SIG VDC fail-safe signal In VDC fail-safe
ON
VDC is normal OFF
CRANKING SIG Crank operation Crank is active
ON
Crank is inactive OFF
CV1 VDC switch-over valve When actuator (switch-over valve) is ac-
tive (“ACTIVE TEST” with CONSULT-III)
or actuator relay is inactive (when in fail-
safe mode)
ON
When actuator (switch-over valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
CV2 VDC switch-over valve When actuator (switch-over valve) is ac-
tive (“ACTIVE TEST” with CONSULT-III)
or actuator relay is inactive (when in fail-
safe mode)
ON
When actuator (switch-over valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
SV1 VDC switch-over valve When actuator (switch-over valve) is ac-
tive (“ACTIVE TEST” with CONSULT-III)
or actuator relay is inactive (when in fail-
safe mode)
ON
When actuator (switch-over valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
SV2 VDC switch-over valve When actuator (switch-over valve) is ac-
tive (“ACTIVE TEST” with CONSULT-III)
or actuator relay is inactive (when in fail-
safe mode)
ON
When actuator (switch-over valve) is not
active and actuator relay is active (igni-
tion switch ON) OFF
DECEL G-SEN Longitudinal acceleration detected by Decel
G-Sensor Vehicle stopped
Approx. 0 G
Vehicle running -1.7 to 1.7 G
EBD WARN LAMP EBD warning lamp
(Note 3) When EBD warning lamp is ON
ON
When EBD warning lamp is OFF OFF
N POSI SIG Transmission range switch signal ON/OFF
condition A/T shift position = N position
ON
A/T shift position = other than N position OFF
P POSI SIG Transmission range switch signal ON/OFF
condition A/T shift position = P position
ON
A/T shift position = other than P position OFF
R POSI SIG Transmission range switch signal ON/OFF
condition A/T shift position = R position
ON
A/T shift position = other than R position OFF
2WD/4WD Drive axle 2WD model
2WD
4WD model 4WD
PRESS SEN2 Brake fluid pressure detected by rear pres-
sure sensor With ignition switch turned ON and brake
pedal released
Approx. 0 bar
With ignition switch turned ON and brake
pedal depressed –40 to 300 bar
Monitor item
Display content Data monitor
Condition Reference value in
normal operation
Revision: March 2010 2008 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-91
< ECU DIAGNOSIS > [VDC/TCS/ABS]
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NOTE:
• 1: Confirm tire pr essure is normal.
• 2: Only 4WD models.
• 3: On and off timing for warning lamp and indicator lamp.
- ABS warning lamp: Refer to BRC-83, "
Description".
- Brake warning lamp: Refer to BRC-84, "
Description".
- VDC OFF indicator lamp: Refer to BRC-85, "
Description".
- SLIP indicator lamp: Refer to BRC-86, "
Description".
TERMINAL LAYOUT
DELTA S SEN Value detected by delta stroke sensor When brake pedal is depressed 1.05 - 1.80 mm
When brake pedal is released
0.00 mm (+0.6/-0.4)
RELEASE SWITCH
NO Active booster signal status When brake pedal is depressed
ON
When brake pedal is released OFF
RELEASE SWITCH
NC Active booster signal status When brake pedal is depressed
OFF
When brake pedal is released ON
STP OFF RLY Stop lamp relay signal When stop lamp relay is ON
ON
When stop lamp relay is OFF OFF
PRES CTRL ACC This item is not used for this model. ——
PRES FAIL ACC This item is not used for this model. ——
Monitor item
Display content Data monitor
Condition Reference value in
normal operation
AWFIA0032ZZ
Revision: March 2010 2008 QX56

BRC-100
< ECU DIAGNOSIS >[VDC/TCS/ABS]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
In case of an electrical malfunction with the ABS, t
he ABS warning lamp, VDC OFF indicator lamp and SLIP
indicator lamp will turn on. In case of an electrical malfunction with the EBD system, the BRAKE warning lamp,
ABS warning lamp, VDC OFF indicator lamp and SLIP indicator lamp will turn on.
The system will revert to one of the follo wing conditions of the Fail-Safe function.
1. For ABS malfunction, only the EBD is operative and the condition of the vehicle is the same condition of vehicles without ABS/TCS/VDC system.
2. For EBD malfunction, the EBD and ABS become inoperat ive, and the condition of the vehicle is the same
as the condition of vehicles without ABS/TCS/VDC or EBD system.
VDC/TCS SYSTEM
In case of TCS/VDC system malfunction, the VDC OFF indicator lamp and SLIP indicator lamp are turned on
and the condition of the vehicle is the same as the c ondition of vehicles without TCS/VDC system. In case of
an electrical malfunction with the TCS/VDC system, the ABS control continues to operate normally without
TCS/VDC control.
DTC No. IndexINFOID:0000000001686373
DTC Items (CONSULT screen terms) Reference
C1101 RR RH SENSOR-1
BRC-29, "
Description"C1102RR LH SENSOR-1
C1103 FR RH SENSOR-1
C1104 FR LH SENSOR-1
C1105 RR RH SENSOR-2
BRC-32, "
Description"C1106RR LH SENSOR-2
C1107 FR RH SENSOR-2
C1108 FR LH SENSOR-2
C1109 BATTERY VOLTAGE [ABNORMAL] BRC-35, "
Description"
C1110CONTROLLER FAILURE BRC-37, "DTC Logic"
C 1111P U M P M O T O R BRC-38, "Description"
C1113G-SENSOR BRC-40, "Description"
C1115ABS SENSOR [ABNORMAL SIGNAL] BRC-43, "Description"
C1116STOP LAMP SW BRC-46, "Description"
C1120FR LH IN ABS SOL BRC-48, "Description"
C1121FR LH OUT ABS SOL BRC-51, "Description"
C1122FR RH IN ABS SOL BRC-48, "Description"
C1123FR RH OUT ABS SOL BRC-51, "Description"
C1124RR LH IN ABS SOL BRC-48, "Description"
C1125RR LH OUT ABS SOL BRC-51, "Description"
C1126RR RH IN ABS SOL BRC-48, "Description"
C1127RR RH OUT ABS SOL BRC-51, "Description"
C1130ENGINE SIGNAL 1
BRC-54, "
Description"
C1131ENGINE SIGNAL 2
C1132 ENGINE SIGNAL 3
C1133 ENGINE SIGNAL 4
C1136 ENGINE SIGNAL 6
C1140 ACTUATOR RLY BRC-56, "
Description"
C1142PRESS SEN CIRCUIT BRC-58, "Description"
C1143ST ANG SEN CIRCUIT
BRC-61, "Description"C1144ST ANG SEN SIGNAL
Revision: March 2010 2008 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-101
< ECU DIAGNOSIS > [VDC/TCS/ABS]
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BRC
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C1145 YAW RATE SENSOR
BRC-40, "Description"C1146SIDE G-SEN CIRCUIT
C1155 BR FLUID LEVEL LOW BRC-64, "
Description"
C1156ST ANG SEN COM CIR BRC-67, "Description"
C1160DECEL G SEN SET BRC-68, "Description"
C1163ST ANGL SEN SAFE BRC-69, "Description"
C1164CV1
BRC-70, "
Description"C1165CV2
C1166 SV1
C1167 SV2
C1170 VARIANT CORDING BRC-37, "
DTC Logic"
C1178ABS ACTIVE BOOSTER SV NG BRC-73, "Description"
C1179ABS DELTA S SEN NG BRC-76, "Description"
C1181ABS ACTIVE BOOSTER RESPONSE NG
BRC-73, "Description"C1184ABS BRAKE RELEASE SW NG
C1185 ABS ACC CU INTERNAL NG BRC-78, "
Description"
C1189ABS BRAKE BOOSTER DEFECT BRC-73, "Description"
U1000CAN COMM CIRCUIT BRC-80, "Description"
DTCItems (CONSULT screen terms) Reference
Revision: March 2010 2008 QX56

BRC-102
< SYMPTOM DIAGNOSIS >[VDC/TCS/ABS]
VDC/TCS/ABS
SYMPTOM DIAGNOSIS
VDC/TCS/ABS
Symptom TableINFOID:0000000001686374
If ABS warning lamp, VDC OFF indicator lamp and SLIP indicator lamp turn ON, perform self-diagnosis.
NOTE:
• 1: The ABS does not operate when the speed is 10 km/h (6 MPH) or less.
• 2: Under the following conditions, ABS is activated and vibration is felt when brake pedal is lightly depressed. However, this
is normal.
- When shifting gears
- When driving on slippery road
- During cornering at high speed
- When passing over bumps or grooves [at approximately 50 mm (1.97 in) or more]
- When pulling away just after starting engine [at approximately 10 km/h (6 MPH) or higher] Symptom
Check itemReference
Excessive ABS function operation fre-
quency Brake force distribution
BRC-103, "
Diag-
nosis Procedure"Looseness of front and rear axle
Wheel sensor and rotor system
Unexpected pedal reaction Brake pedal stroke
BRC-104, "
Diag-
nosis Procedure"Make sure the braking force is sufficient when the ABS is not operating.
The braking distance is long Check stopping distance when the ABS is not operating. BRC-105, "
Diag-
nosis Procedure"
ABS function does not operate (Note 1) ABS actuator and electric
unit (control unit)BRC-106, "Diag-
nosis Procedure"
Pedal vibration or ABS operation sound
occurs (Note 2)Brake pedal
BRC-107, "Diag-
nosis Procedure"ABS actuator and electric unit (control unit)
Vehicle jerks during VDC/TCS/ABS con-
trol ABS actuator and electric unit (control unit)
BRC-108, "
Diag-
nosis Procedure"TCM
ECM
Revision: March 2010 2008 QX56

EXCESSIVE ABS FUNCTION OPERATION FREQUENCYBRC-103
< SYMPTOM DIAGNOSIS > [VDC/TCS/ABS]
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EXCESSIVE ABS FUNCTION OPERATION FREQUENCY
Diagnosis ProcedureINFOID:0000000001686375
1.CHECK START
Check front and rear brake force di stribution using a brake tester.
Is the inspection result normal?
YES >> GO TO 2
NO >> Check brake system.
2.CHECK FRONT AND REAR AXLE
Make sure that there is no excessive play in the front and rear axles. Refer to front: FAX-6, "
On-Vehicle
Inspection and Service", Rear: RAX-6, "On-Vehicle Inspection and Service".
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace malfunctioning components.
3.CHECK WHEEL SENSOR AND SENSOR ROTOR
Check the following.
• Wheel sensor installation for damage.
• Sensor rotor installation for damage.
• Wheel sensor connector connection.
• Wheel sensor harness inspection.
Is the inspection result normal?
YES >> GO TO 4
NO >> • Replace wheel sensor or sensor rotor. Refer to BRC-114, "
Removal and Installation".
• Repair harness.
4.CHECK ABS WARNING LAMP DISPLAY
Make sure that the ABS warning lamp is turned off af ter the ignition switch is turned ON or when driving.
Is the ABS warning lamp illuminated?
YES >> Perform self-diagnosis. Refer to BRC-24, "CONSULT-III Function (ABS)".
NO >> Normal
Revision: March 2010 2008 QX56

BRC-104
< SYMPTOM DIAGNOSIS >[VDC/TCS/ABS]
UNEXPECTED PEDAL REACTION
UNEXPECTED PEDAL REACTION
Diagnosis ProcedureINFOID:0000000001686376
1.CHECK BRAKE PEDAL STROKE
Check brake pedal stroke. Refer to BR-15, "
Inspection and Adjustment".
Is the stroke too large?
YES >> • Bleed air from brake tube and hose. Refer to BR-17, "Bleeding Brake System".
• Check brake pedal, brake booster, and master cylinder for mount play, looseness, brake system fluid leakage, etc. Refer to BR-15, "
Inspection and Adjustment" (brake pedal), BR-12, "On
Board Inspection" (master cylinder), BR-10, "Inspection" (brake booster).
NO >> GO TO 2
2.CHECK FUNCTION
Disconnect ABS actuator and electric unit (control unit) c onnector to deactivate ABS. Check if braking force is
normal in this condition. Connect connector after inspection.
Is the inspection result normal?
YES >> Normal
NO >> Check brake system.
Revision: March 2010 2008 QX56