INFINITI QX56 2007 Factory Service Manual

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-43
< SERVICE INFORMATION >[VDC/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC
N
O
P
Active Booster System InspectionINFOID:0000000003532794
INSPECTION PROCEDURE
1.DISPLAY SELF DIAGNOSIS RESULTS
Check self-diagnosis results.
Is the above displayed in the self-diagnosis display items?
YES or NO
YES >> GO TO 2.
NO >> Inspection End.
2.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the active booster connector E49 and ABS actuator and electric unit (control unit) connector
E125 and inspect the terminals for deformation, disconnection, looseness, or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair connector.
3.ACTIVE BOOSTER CIRCUIT INSPECTION
1. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and
active booster connector E49.
2. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and body
ground.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connector.
Self-diagnosis results
ABS ACTIVE BOOSTER SV NG
ABS ACTIVE BOOSTER RESPONSE NG
ABS BRAKE RELEASE SW NG
ABS BRAKE BOOSTER DEFECT
ABS actuator and electric unit (con-
trol unit) connector E125Active booster connector
E49Continuity
17 3
Ye s 27 1
28 5
30 2
31 4
ABS actuator and electric unit (con-
trol unit) connector E125Body ground Continuity
17
—No 27
28
30
31

BRC-44
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
4.ACTIVE BOOSTER SENSOR INSPECTION
1. Reconnect the active booster and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "RELEASE SW NO" and "RELEASE SW NC" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace active booster.
Delta Stroke Sensor System InspectionINFOID:0000000003532795
INSPECTION PROCEDURE
1.DISPLAY SELF DIAGNOSIS RESULTS
Check self-diagnosis result display item.
Is the above displayed in the self-diagnosis display items?
YES or NO
YES >> GO TO 2.
NO >> Inspection End.
2.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the delta stroke sensor connector E114 and ABS actuator and electric unit (control unit) con-
nector E125 and inspect the terminals for deformation, disconnection, looseness, or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair connector.
3.DELTA STROKE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and delta
stroke sensor connector E114.
2. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and body
ground.ConditionData monitor display
RELEASE SW NO RELEASE SW NC
When brake pedal is depressed ON OFF
When brake pedal is released OFF ON
Self-diagnosis results
ABS DELTA S SEN NG
ABS actuator and electric unit
(control unit) connector E125Delta stroke sensor
connector E114Continuity
26 1
Ye s 39 3
40 5
ABS actuator and electric unit (con-
trol unit) connector E125Body ground Continuity
26
—No 39
40

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-45
< SERVICE INFORMATION >[VDC/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC
N
O
P
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connector.
4.DELTA STROKE SENSOR INSPECTION
1. Reconnect the delta stroke sensor and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "DELTA S SEN" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace delta stroke sensor.
Pressure Sensor System InspectionINFOID:0000000003532796
FRONT PRESSURE INSPECTION PROCEDURE
1.DISPLAY SELF DIAGNOSIS RESULTS
Check self-diagnosis result display item.
Is the above displayed in the self-diagnosis display items?
YES or NO
YES >> GO TO 2.
NO >> Inspection End.
2.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 deformation, disconnection, looseness, or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair connector.
3.FRONT PRESSURE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between the ABS actuator and electric unit (control unit) harness connector E125
and front pressure sensor harness connector E31.
2. Measure the continuity between the ABS actuator and electric unit (control unit) harness connector E125
and body ground.ConditionData monitor display (Approx.)
DELTA S SEN
When brake pedal is released 0.00 mm (+0.6/-0.4)
When brake pedal is depressed 1.05–1.80 mm
Self-diagnosis results
PRESS SEN CIRCUIT
ABS actuator and electric unit
(control unit) harness connector
E125Front pressure sensor har-
ness connector E31Continuity
18 3
Ye s 19 1
20 2

BRC-46
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connector.
4.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.
OK or NG
OK >> Inspection End.
NG >> Replace pressure sensor.
REAR PRESSURE INSPECTION PROCEDURE
1.DISPLAY SELF DIAGNOSIS RESULTS
Check self-diagnosis result display item.
Is the above displayed in the self-diagnosis display items?
YES or NO
YES >> GO TO 2.
NO >> Inspection End.
2.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 deformation, disconnection, looseness, or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair connector.
3.REAR PRESSURE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and rear
pressure sensor connector E32.ABS actuator and electric unit
(control unit) harness connector
E125Body ground Continuity
18
—No 19
20
ConditionData monitor display (Approx.)
PRESS SENSOR
When brake pedal is depressed Positive value
When brake pedal is released 0 bar
Self-diagnosis results
PRESS SEN CIRCUIT
ABS actuator and electric unit (con-
trol unit) connector E125Rear pressure sensor con-
nector E32Continuity
21 1
Ye s 22 3
23 2

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-47
< SERVICE INFORMATION >[VDC/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC
N
O
P
2. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and body
ground.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connector.
4.REAR PRESSURE SENSOR INSPECTION
1. Reconnect the rear pressure sensor and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "PRESS SEN 2" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace rear pressure sensor.
Steering Angle Sensor Safe Mode InspectionINFOID:0000000003532797
INSPECTION PROCEDURE
1.INDICATOR LAMP CHECK
Check that VDC OFF indicator lamp is on.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Adjust steering angle sensor neutral position. Refer to BRC-54, "
Adjustment of Steering Angle Sensor Neutral
Position".
OK or NG
OK >> GO TO 3.
NG >> Check steering angle sensor. Refer to BRC-36, "
Steering Angle Sensor System".
3.INDICATOR LAMP CHECK
Check that VDC OFF indicator lamp is off.
OK or NG
OK >> GO TO 4.
NG >> Perform basic inspection. Refer to BRC-22, "
Basic Inspection".
4.CHECK SELF-DIAGNOSTIC RESULTS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
NOTE:ABS actuator and electric unit (con-
trol unit) connector E125Body ground Continuity
21
—No 22
23
ConditionData monitor display (Approx.)
PRESS SEN 2
When brake pedal is depressed Positive value
When brake pedal is released 0 bar
Self-diagnosis results
ST ANGL SEN SAFE

BRC-48
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
When self-diagnostic results show items other than those above, perform repair or replacement for the item
indicated and repeat self-diagnosis.
Is the above displayed on self-diagnosis display?
YES >> Erase error memory.
NO >> Inspection End.
CAN Communication System InspectionINFOID:0000000003532798
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn ignition switch OFF, disconnect the ABS actuator and electric unit (control unit) connector, and check
the terminals for deformation, disconnection, looseness, and so on. If there is a malfunction, repair or
replace the terminal.
2. Reconnect connector to perform self-diagnosis.
Is "CAN COMM CIRCUIT" displayed in self-diagnosis display items?
YES >> Print out the self-diagnostic results, and refer to LAN-7.
NO >> Connector terminal is loose, damaged, open, or shorted.
ICC System InspectionINFOID:0000000003532799
INSPECTION PROCEDURE
1.SELF-DIAGNOSIS RESULT CHECK
Perform self-diagnosis of ICC control unit. Refer to ACS-30, "
Self-Diagnostic Function".
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform ICC control unit self-diagnosis again.
NO >> GO TO 2.
2.CONNECTOR INSPECTION
Disconnect the ABS actuator and electric unit (control unit) connector and the ICC control unit connector and
check the terminals for deformation, disconnection, looseness or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace as necessary.
3.ICC CONTROL UNIT CIRCUIT INSPECTION
1. Measure the continuity between ABS actuator and electric unit (control unit) connector E125 and ICC con-
trol unit connector B13.
2. Measure the continuity between ABS actuator and electric unit (control unit) connector E125 and body
ground.
OK or NG
OK >> Replace ABS actuator and electric unit (control unit). Refer to BRC-58, "Removal and Installation"
NG >> Repair or replace harness or connector.
Inspection for Self-Diagnosis Result "ST ANG SEN SIGNAL"INFOID:0000000003532800
INSPECTION PROCEDURE
ABS actuator and electric unit (con-
trol unit) connector E125ICC control unit connector
B13Continuity
710Yes
ABS actuator and electric unit (con-
trol unit) connector E125Body ground Continuity
7—No

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-49
< SERVICE INFORMATION >[VDC/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC
N
O
P
1.DISPLAY SELF-DIAGNOSIS RESULTS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
Do self-diagnosis results indicate anything other than shown above?
YES >> Perform repair or replacement for the item indicated.
NO >> Perform adjustment of steering angle sensor neutral position. GO TO 2.
2.PERFORM SELF-DIAGNOSIS AGAIN
1. Turn the ignition switch to OFF and then to ON and erase self-diagnosis results.
2. Perform ABS actuator and electric unit (control unit) self-diagnosis again.
Are any self-diagnosis results displayed?
YES >> Replace steering angle sensor. Refer to BRC-60, "Removal and Installation".
NO >> Inspection End.
Inspection for Self-Diagnosis Result "DECEL G SEN SET"INFOID:0000000003532801
INSPECTION PROCEDURE
1.PERFORM SELF-DIAGNOSIS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
Do self-diagnosis results indicate anything other than shown above?
YES >> Perform repair or replacement for the item indicated.
NO >> Perform calibration of decel G sensor. Refer to BRC-54, "
Calibration of Decel G Sensor". GO TO
2.
2.PERFORM SELF-DIAGNOSIS AGAIN
1. Turn the ignition switch to OFF and then to ON and erase self-diagnosis results.
2. Perform ABS actuator and electric unit (control unit) self-diagnosis again.
Are any self-diagnosis results displayed?
YES >> Replace yaw rate/side/decel G sensor. Refer to BRC-61, "Removal and Installation".
NO >> Inspection End.
Self-diagnosis results
ST ANG SEN SIGNAL
Self-diagnosis results
DECEL G SEN SET

BRC-50
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSES FOR SYMPTOMS
TROUBLE DIAGNOSES FOR SYMPTOMS
ABS Works FrequentlyINFOID:0000000003532802
INSPECTION PROCEDURE
1.CHECK WARNING LAMP ACTIVATION
Make sure warning lamp remains off while driving.
OK or NG
OK >> GO TO 2.
NG >> Carry out self-diagnosis. Refer to BRC-26, "
CONSULT-II Function (ABS)".
2.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 >> GO TO 3.
NG >> Repair or replace as necessary.
3.CHECK FRONT AND REAR AXLES
Check wheel bearing axial end play. Refer to FAX-5, "
On-Vehicle Inspection and Service" (front) or RAX-5,
"On-Vehicle Inspection and Service" (rear).
OK or NG
OK >> GO TO 4.
NG >> Repair as necessary.
4.CHECK BRAKE FLUID PRESSURE
Check brake fluid pressure distribution.
Refer to BRC-22, "
Basic Inspection".
Is brake fluid pressure distribution normal?
YES >> Inspection End.
NO >> Perform Basic Inspection. Refer to BRC-22, "
Basic Inspection".
Unexpected Pedal ActionINFOID:0000000003532803
INSPECTION PROCEDURE
1.CHECK WARNING LAMP ACTIVATION
Make sure warning lamp remains off while driving.
OK or NG
OK >> GO TO 2.
NG >> Carry out self-diagnosis. Refer to BRC-26, "
CONSULT-II Function (ABS)".
2.CHECK BRAKE PEDAL STROKE
Check brake pedal stroke.
Is pedal stroke excessive?
YES >> Perform Basic Inspection. Refer to BRC-22, "Basic
Inspection".
NO >> GO TO 3.
SBR540A

TROUBLE DIAGNOSES FOR SYMPTOMS
BRC-51
< SERVICE INFORMATION >[VDC/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC
N
O
P
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-52
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSES FOR SYMPTOMS
1.CHECK SYMPTOM
1. Apply brake.
2. Start engine.
Does the symptom occur only when engine is started?
YES >> Carry out self-diagnosis. Refer to BRC-26, "CONSULT-II Function (ABS)".
NO >> GO TO 2.
2.RECHECK SYMPTOM
Does the symptom occur only when electrical equipment switches (such as headlamps) are turned on?
YES >> Check for radio, antenna or related wiring that is routed too close to the ABS actuator and electric
unit (control unit) and reroute as necessary.
NO >> Go to BRC-50, "
ABS Works Frequently".
Vehicle Jerks During TCS/VDC ActivationINFOID:0000000003532807
INSPECTION PROCEDURE
1.ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform the ABS actuator and electric unit (con-
trol unit) self-diagnosis again.
NO >> GO TO 2.
2.ENGINE SPEED SIGNAL INSPECTION
Perform data monitor with CONSULT-II for the ABS actuator and electric unit (control unit).
Is the engine speed at idle 400 rpm or higher?
YES >> GO TO 4.
NO >> GO TO 3.
3.ECM SELF-DIAGNOSIS
Perform ECM self-diagnosis.
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform the ECM self-diagnosis again.
NO >> GO TO 4.
4.TCM SELF-DIAGNOSIS
Perform TCM self-diagnosis.
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform the TCM self-diagnosis again.
NO >> GO TO 5.
5.CONNECTOR INSPECTION
Disconnect the ABS actuator and electric unit (control unit) connector and the ECM connectors and check the
terminals for deformation, disconnection, looseness or damage.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace as necessary.
6.CAN COMMUNICATION INSPECTION
Check the CAN communication system. Refer to BRC-48, "
CAN Communication System Inspection".
OK or NG
OK >> Inspection End.
NG >> Refer to LAN-7
.