Infiniti QX56 (JA60). Manual - part 147

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-39, "Description"

C1146

SIDE G-SEN CIRCUIT

C1155

BR FLUID LEVEL LOW

BRC-63, "Description"

C1156

ST ANG SEN COM CIR

BRC-66, "Description"

C1160

DECEL G SEN SET

BRC-67, "Description"

C1163

ST ANGL SEN SAFE

BRC-68, "Description"

C1164

CV1

BRC-69, "Description"

C1165

CV2

C1166

SV1

C1167

SV2

C1170

VARIANT CODING

BRC-36, "DTC Logic"

C1178

ABS ACTIVE BOOSTER SV NG

BRC-72, "Description"

C1179

ABS DELTA S SEN NG

BRC-75, "Description"

C1181

ABS ACTIVE BOOSTER RESPONSE NG

BRC-72, "Description"

C1184

ABS BRAKE RELEASE SW NG

C1185

ABS ACC CU INTERNAL NG

BRC-77, "Description"

C1189

ABS BRAKE BOOSTER DEFECT

BRC-72, "Description"

U1000

CAN COMM CIRCUIT

BRC-79, "Description"

DTC

Items (CONSULT screen terms)

Reference

BRC-102

< SYMPTOM DIAGNOSIS >

[VDC/TCS/ABS]

VDC/TCS/ABS

SYMPTOM DIAGNOSIS

VDC/TCS/ABS

Symptom Table

INFOID:0000000005148085

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 item

Reference

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

EXCESSIVE ABS FUNCTION OPERATION FREQUENCY

BRC-103

< SYMPTOM DIAGNOSIS >

[VDC/TCS/ABS]

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EXCESSIVE ABS FUNCTION OPERATION FREQUENCY

Diagnosis Procedure

INFOID:0000000005148086

1.

CHECK START

Check front and rear brake force distribution 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 after the ignition switch is turned ON or when driving. 
Is the ABS warning lamp illuminated?

YES

>> Perform self-diagnosis. Refer to 

BRC-23, "CONSULT-III Function (ABS)"

.

NO

>> Normal

BRC-104

< SYMPTOM DIAGNOSIS >

[VDC/TCS/ABS]

UNEXPECTED PEDAL REACTION

UNEXPECTED PEDAL REACTION

Diagnosis Procedure

INFOID:0000000005148087

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) connector 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.