INFINITI QX56 2008 Factory Service Manual

BRC-4
< BASIC INSPECTION >[VDC/TCS/ABS]
DIAGNOSIS AND REPAIR WORKFLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Work FlowINFOID:0000000001686231
PRECAUTIONS FOR DIAGNOSIS
If steering angle sensor, steering system parts, suspension system parts, ABS actuator and electric unit (con-
trol unit) or tires have been replaced, or if wheel a
lignment has been adjusted, be sure to adjust neutral posi-
tion of steering angle sensor before driving. Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE
SENSOR NEUTRAL POSITION : Description".
Revision: March 2010 2008 QX56

DIAGNOSIS AND REPAIR WORKFLOWBRC-5
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OVERALL SEQUENCE
DETAIED FLOW
1.COLLECT THE INFORMATION FROM THE CUSTOMER
Get the detailed information from the customer about the symptom (the condition and the environment when
the incident/malfunction occurred) usi ng the diagnosis worksheet. Refer to BRC-7, "
Diagnostic Work Sheet".
>> GO TO 2
JSFIA0010GB
Revision: March 2010 2008 QX56

BRC-6
< BASIC INSPECTION >[VDC/TCS/ABS]
DIAGNOSIS AND REPAIR WORKFLOW
2.PERFORM THE SELF-DIAGNOSIS
Check the DTC display with the self-diagnosis function. Refer to BRC-24, "
CONSULT-III Function (ABS)".
Is there any DTC displayed?
YES >> GO TO 3
NO >> GO TO 4
3.PERFORM THE SYSTEM DIAGNOSIS
Perform the diagnosis applicable to the displayed DTC. Refer to BRC-100, "
DTC No. Index".
>> GO TO 7
4.CHECK THE SYMPTOM THAT IS NOT CONSIDERED A SYSTEM MALFUNCTION
Check that the symptom is a normal operation that is not considered a system malfunction. Refer to BRC-109,
"Description".
Is the symptom a normal operation?
YES >> Inspection End
NO >> GO TO 5
5.CHECK THE WARNING LAMP AND I NDICATOR LAMP FOR ILLUMINATION
Check that the warning lamp and indicator lamp illuminate.
• 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".
Is ON/OFF timing normal?
YES >> GO TO 6
NO >> GO TO 2
6.PERFORM THE DIAGNOSIS BY SYMPTOM
Perform the diagnosis applicable to the symptom.
>> GO TO 7
7.REPAIR OR REPLACE THE MALFUNCTIONING PARTS
Repair or replace the specified malfunctioning parts.
>> GO TO 8
8.FINAL CHECK
Perform the self-diagnosis again, and check that the malfunction is repaired completely. After checking, erase
the self-diagnosis memory. Refer to BRC-24, "
CONSULT-III Function (ABS)".
Is no other DTC present and the repair completed?
YES >> Inspection End
NO >> GO TO 3
Revision: March 2010 2008 QX56

DIAGNOSIS AND REPAIR WORKFLOWBRC-7
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Diagnostic Work SheetINFOID:0000000001686232
SFIA3265E
Revision: March 2010 2008 QX56

BRC-8
< BASIC INSPECTION >[VDC/TCS/ABS]
INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
ADDITIONAL SERVICE WHEN
REPLACING CONTROL UNIT
ADDITIONAL SERVICE WHEN REPL ACING CONTROL UNIT : Description
INFOID:0000000001686233
After replacing the ABS actuator and electric unit (control unit), perform the following procedures:
• Neutral position adjustment for the steering angle sensor
• Calibration of the decel G sensor
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Re-
quirement
INFOID:0000000001686234
1.PERFORM THE NEUTRAL POSITION ADJUST MENT FOR THE STEERING ANGLE SENSOR
Perform the neutral position adjustm ent for the steering angle sensor.
>> Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION : Spe-
cial Repair Requirement", GO TO 2
2.PERFORM CALIBRATION OF THE DECEL G SENSOR
Perform calibration of the decel G sensor.
>> Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Special Repair Requirement".
ADJUSTMENT OF STEERING ANGL E SENSOR NEUTRAL POSITION
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION : Description
INFOID:0000000001686235
Refer to the table below to determine if adjustment of steering angle sensor neutral position is required.
×: Required –: Not required
ADJUSTMENT OF STEERING ANGLE SENS OR NEUTRAL POSITION : Special Re-
pair Requirement
INFOID:0000000001686236
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
CAUTION:
To adjust neutral position of steering angl e sensor, make sure to use CONSULT-III
(Adjustment cannot be done without CONSULT-III)
1.ALIGN THE VEHICLE STATUS
Stop vehicle with front wheels in straight-ahead position.
Situation Adjustment of steering angle sensor neutral position
Removing/Installing ABS actuator and electric unit (control unit) —
Replacing ABS actuator and electric unit (control unit) ×
Removing/Installing steering angle sensor ×
Replacing steering angle sensor ×
Removing/Installing steering components ×
Replacing steering components ×
Removing/Installing suspension components ×
Replacing suspension components ×
Change tires to new ones —
Tire rotation —
Adjusting wheel alignment ×
Battery disconnection ×
Revision: March 2010 2008 QX56

INSPECTION AND ADJUSTMENTBRC-9
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>> GO TO 2
2.PERFORM THE NEUTRAL POSITION ADJUST MENT FOR THE STEERING ANGLE SENSOR
1. On the CONSULT-III screen, touch “WORK SUPP ORT” and “ST ANG SEN ADJUSTMENT” in order.
2. Touch “START”. CAUTION:
Do not touch steering wheel whil e adjusting steering angle sensor.
3. After approximately 10 seconds, touch “END”. NOTE:
After approximately 60 seconds, it ends automatically.
4. Turn ignition switch OFF, then turn it ON again. CAUTION:
Be sure to perform above operation.
>> GO TO 3
3.CHECK DATA MONITOR
1. Run vehicle with front wheels in straight-ahead position, then stop.
2. Select “DATA MONITOR”. Then make sure “STR ANGLE SIG” is within 0 ±2.5 °.
Is the steering angle within the specified range?
YES >> GO TO 4
NO >> Perform the neutral position adjustment fo r the steering angle sensor again, GO TO 1
4.ERASE THE SELF-DIAGNOSIS MEMORY
Erase the self-diagnosis memory of the ABS ac tuator and electric unit (control unit) and ECM.
• ABS actuator and electric unit (control unit): Refer to BRC-24, "
CONSULT-III Function (ABS)".
• ECM: Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Are the memories erased?
YES >> Inspection End
NO >> Check the items indica ted by the self-diagnosis.
CALIBRATION OF DECEL G SENSOR
CALIBRATION OF DECEL G SENSOR : DescriptionINFOID:0000000001686237
Refer to the table below to determine if calibration of the decel G sensor is required.
×: Required –: Not required
CALIBRATION OF DECEL G SENSOR : Special Repair RequirementINFOID:0000000001686238
CALIBRATION OF DECEL G SENSOR
CAUTION:
To calibrate the decel G sensor, make sure to use CONSULT-III
Situation Calibration of decel G sensor
Removing/Insta lling ABS actuator and electr ic unit (control unit) —
Replacing ABS actuator and elec tric unit (control unit) ×
Removing/Installing steering angle sensor ×
Replacing steering angle sensor ×
Removing/Installing steering components ×
Replacing steering components ×
Removing/Installing suspension components ×
Replacing suspension components ×
Change tires to new ones —
Tire rotation —
Adjusting wheel alignment ×
Revision: March 2010 2008 QX56

BRC-10
< BASIC INSPECTION >[VDC/TCS/ABS]
INSPECTION AND ADJUSTMENT
(Calibration cannot be
done without CONSULT-III)
1.ALIGN THE VEHICLE STATUS
Stop vehicle with front wheels in straight-ahead position.
>> GO TO 2
2.PERFORM CALIBRATION OF DECEL G SENSOR
1. On the CONSULT-III screen, touch “WORK SUPPORT” and “DECEL G SEN CALIBRATION” in order.
2. Touch “START”.
3. After approximately 10 seconds, touch “END”. NOTE:
After approximately 60 seconds, it ends automatically.
4. Turn ignition switch OFF, then turn it ON again.
CAUTION:
Be sure to perform above operation.
>> GO TO 3
3.CHECK DATA MONITOR
1. Run vehicle with front wheels in straight-ahead position, then stop.
2. Select “DATA MONITOR”. Then make sure “DECEL G SEN” is within ± 0.08G.
Is the inspection result normal?
YES >> GO TO 4
NO >> Perform calibration of decel G sensor again, GO TO 1
4.ERASE THE SELF-DIAGNOSIS MEMORY
Erase the self-diagnosis memory of the ABS ac tuator and electric unit (control unit) and ECM.
• ABS actuator and electric unit (control unit): Refer to BRC-24, "
CONSULT-III Function (ABS)".
• ECM: Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Are the memories erased?
YES >> Inspection End
NO >> Check the items indicated by the self-diagnosis.
Revision: March 2010 2008 QX56

VDC
BRC-11
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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FUNCTION DIAGNOSIS
VDC
System DiagramINFOID:0000000001686239
AWFIA0065GB
Revision: March 2010 2008 QX56

BRC-12
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
VDC
Hydraulic Circuit Diagram
INFOID:0000000005875001
System DescriptionINFOID:0000000001686240
• Vehicle Dynamics Control system detects driver ′s steering operation amount and brake pedal travel from
steering angle sensor and pressure sensors. Using information from yaw rate/side/decel G sensor and
wheel sensor, VDC judges driving condition (conditions of under steer and over steer) to improve vehicle
driving stability by controlling brake application to 4 wheels and engine output.
• During VDC operation, it inform s driver of system operation by flashing SLIP indicator lamp.
• Electrical system diagnosis by CONSULT-III is available.
WFIA0187E
Revision: March 2010 2008 QX56

VDC
BRC-13
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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Component Parts LocationINFOID:0000000001686241
1. Front wheel sensor LH E18 Front wheel sensor RH E117 2. Delta stroke sensor E114 3. Brake fluid level switch E21
4. Active booster E49 5. Front pressure sensor E31 6. Rear pressure sensor E32
7. ABS actuator and electric unit (con- trol unit) E125 8. Stop lamp switch E38
9. Combination meter M23, M24
AWFIA0713GB
Revision: March 2010 2008 QX56