2001 INFINITI QX4 IDX

G Sensor and Circuit
DIAGNOSTIC PROCEDURENBBR0114Malfunction code No. 17
1 INSPECTION START
G sensor inspection
SBR504E
©GO TO 2.
2 CHECK FUSE
Check 7.5A fuse No. 7 for ABS actuator and electric unit. For fuse layout, refer to EL-16, ªPOWER SUPPLY ROUTINGº.
Is fuse OK?
Ye s©GO TO 3.
No©Replace fuse.
3 CHECK CONNECTOR
1. Disconnect connectors from ABS actuator and electric unit and G sensor. Check terminals for damage or loose connec-
tion. Then reconnect connectors.
2. Carry out self-diagnosis again.
Does warning lamp activate again?
Ye s©GO TO 4.
No©INSPECTION END
4 CHECK G SENSOR
Refer to ªG SENSORº in ªElectrical Components Inspectionº, BR-67.
Is resistance within specifications?
Ye s©GO TO 5.
No©Replace G sensor.
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TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
G Sensor and Circuit
BR-65

SBR844DF
ELECTRICAL COMPONENT INSPECTION=NBBR0115G Sensor (4WD models only)NBBR0115S01CAUTION:
The G sensor is easily damaged if it sustains an impact. Be
careful not to drop or bump it.
1. Measure resistance between terminals 2 and 51 of G sensor
unit connector.
G sensor conditionResistance between ter-
minals 2 and 51G sensor switch condi-
tion
Installed in vehicle 1.4 - 1.6 kWªONº
Tilted as shown in figure 4.7 - 5.5 kWªOFFº
2. Measure resistance between terminals 1 and 17 of the G sen-
sor unit connector.
Resistance: 70 - 124W
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TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
G Sensor and Circuit (Cont'd)
BR-67

1. ABS Works FrequentlyNBBR0107
1 CHECK BRAKE FLUID PRESSURE
Check brake fluid pressure distribution.
Refer to ªInspectionº, ªLOAD SENSING VALVEº, BR-12.
Is brake fluid pressure distribution normal?
Ye s©GO TO 2.
No©Repair. Then perform Preliminary Check.
Refer to BR-50.
2 CHECK WHEEL SENSOR
1. Check wheel sensor connector for terminal damage or loose connections.
2. Perform wheel sensor mechanical check.
Refer to ª7. CHECK SENSOR ROTORº in ªDIAGNOSTIC PROCEDUREº, ªWheel Sensor or Rotorº, BR-56.
Is wheel sensor mechanism OK?
Ye s©GO TO 3.
No©Repair.
3 CHECK FRONT AXLE
Check front axles for excessive looseness. Refer to AX-4, ªFront Wheel Bearingº.
Is front axle installed properly?
Ye s©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-70.
No©Repair.
2. Unexpected Pedal ActionNBBR0108
1 CHECK BRAKE PEDAL STROKE
Check brake pedal stroke.
SBR540A
Is brake pedal stroke excessively large?
Ye s©Perform Preliminary Check. Refer to BR-50.
No©GO TO 2.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
1. ABS Works Frequently
BR-69

NOTE:
Stopping distance may be longer for vehicles without ABS when
road condition is slippery.
4. ABS Does Not WorkNBBR0110
1 CHECK WARNING LAMP INDICATION
Does the ABS warning lamp activate?
YesorNo
Ye s©Carry out self-diagnosis. Refer to BR-41, 44.
No©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-70.
NOTE:
ABS does not work when vehicle speed is under 10 km/h (6 MPH).
5. Pedal Vibration and NoiseNBBR0111
1 INSPECTION START
Pedal vibration and noise inspection
SAT797A
©GO TO 2.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
3. Long Stopping Distance (Cont'd)
BR-71

3 CHECK WARNING LAMP ACTIVATE
Disconnect ABS actuator and electric unit connector.
SBR672E
Does the warning lamp activate?
Ye s©Replace ABS actuator and electric unit.
No©GO TO 4.
4 CHECK HARNESS FOR SHORT
1. Disconnect ABS actuator and electric unit connector and combination meter connector M24.
2. Check continuity between ABS actuator and electric unit connector E111 (body side) terminal 10 (2WD) or 21 (4WD)
and ground.
SBR499E
Continuity should not exist.
Does continuity exist?
Ye s©Repair harness or connectors.
No©Check combination meter.
Refer to EL-114, ªWARNING LAMPSº.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
6. Warning Lamp Does Not Come On When Ignition Switch Is Turned On (Cont'd)
BR-73

5 CHECK ABS ACTUATOR AND ELECTRIC UNIT POWER SUPPLY CIRCUIT
1. Disconnect ABS actuator and electric unit connector.
2. Check voltage between ABS actuator and electric unit connector E111 (body side) terminal 15 and ground.
SBR495E
Does battery voltage exist when ignition switch is turned ON?
Ye s©GO TO 6.
No©Check the following.
If NG, repair harness or connector.
IHarness connector E111
IHarness for open or short between ABS actuator and electric unit and fuse
6 CHECK WARNING LAMP
1. Disconnect ABS actuator and electric unit connector.
2. Connect suitable wire between ABS actuator and electric unit connector E111 (body side) terminal 10 (2WD) or 21
(4WD) and ground.
SBR502E
Does the warning lamp deactivate?
Ye s©Replace ABS actuator and electric unit.
No©GO TO 7.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
7. Warning Lamp Stays On When Ignition Switch Is Turned On (Cont'd)
BR-75

8. Vehicle Vibrates Excessively When ABS Is
Operating
=NBBR0078IWhile ABS is operating, brake pedal vibrates slightly. This is
not a problem.
IIf vehicle vibration is greater in the AUTO mode than in the
2WD mode, there is the possibility of failure in the communi-
cation line between the ABS control unit and transfer control
unit. Check and locate the cause of the problem.
1 INSPECTION START
Inspection for excessive vibration of vehicle
SBR508E
©GO TO 2.
2 CARRY OUT SELF-DIAGNOSIS
Perform self-diagnosis for the ABS actuator and electric unit and transfer control unit.
Are there any malfunctions?
Ye s©GO TO 3.
No©GO TO 4.
3 INSPECTION OR REPAIR
Inspect or repair the system according to the self-diagnostic item.
OK©GO TO 4.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
8. Vehicle Vibrates Excessively When ABS Is Operating
BR-77

6 CHECK ABS OPERATING SIGNAL
1. Connect CONSULT-II to Data Link Connector.
2. Turn ignition switch ªONº. Set CONSULT-II in the active test mode to output an ABS operating signal.
(Refer to ªACTIVE TEST PROCEDUREº, ªCONSULT-II Inspection Procedureº, BR-47.)
3. An ABS operating signal lasts for 10 seconds. During the time the signal is being output, check resistance between
transfer control unit connector terminal 32 and ground.
Resistance: 0.5W, max.
SBR680E
Is resistance within specifications?
Ye s©CHECK transfer control unit.
Refer to TF-86, ªTROUBLE DIAGNOSIS FOR ABS OPERATION SIGNALº.
No©Replace ABS actuator and electric unit.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
8. Vehicle Vibrates Excessively When ABS Is Operating (Cont'd)
BR-79