2001 INFINITI QX4 rotor

Malfunction Code/Symptom ChartNBBR0101
Code No. (No. of warning lamp flashes) Malfunctioning part Reference Page
12 Self-diagnosis could not detect any malfunctions. Ð
17*4 G sensor and circuit BR-65
18*1 Sensor rotor BR-56
21*1 Front right sensor (open-circuit) BR-56
22*1 Front right sensor (short-circuit) BR-56
25*1 Front left sensor (open-circuit) BR-56
26*1 Front left sensor (short-circuit) BR-56
31*1 Rear right sensor (open-circuit) BR-56
32*1 Rear right sensor (short-circuit) BR-56
35*1 Rear left sensor (open-circuit) BR-56
36*1 Rear left sensor (short-circuit) BR-56
41 Actuator front right outlet solenoid valve BR-59
42 Actuator front right inlet solenoid valve BR-59
45 Actuator front left outlet solenoid valve BR-59
46 Actuator front left inlet solenoid valve BR-59
55 Actuator rear outlet solenoid valve BR-59
56 Actuator rear inlet solenoid valve BR-59
57*2 Power supply (Low voltage) BR-63
61*3 Actuator motor or motor relay BR-61
63 Solenoid valve relay BR-59
71 Control unit BR-68
Warning lamp stays on when ignition
switch is turned ON.Control unit power supply circuit
Warning lamp bulb circuit
Control unit or control unit connector
Solenoid valve relay stuck
Power supply for solenoid valve relay coilBR-74
ABS works frequently Ð BR-69
Unexpected pedal action Ð BR-69
Long stopping distance Ð BR-70
ABS does not work Ð BR-71
Pedal vibration and noise Ð BR-71
Warning lamp does not come on
when ignition switch is turned ON.Fuse, warning lamp bulb or warning lamp circuit
Control unitBR-72
Vehicle vibrates excessively when ABS is
operating.ABS control unit to TCM circuit BR-77
*1: If one or more wheels spin on a rough or slippery road for 40 seconds or more, the ABS warning lamp will illuminate. This does not
indicate a malfunction. Only in the case of the short-circuit (Code Nos. 26, 22, 32 and 36), after repair the ABS warning lamp also illu-
minates when the ignition switch is turned ON. In this case, drive the vehicle at speeds greater than 30 km/h (19 MPH) for approxi-
mately 1 minute as specified in ªSELF-DIAGNOSIS PROCEDUREº, BR-41. Check to ensure that the ABS warning lamp goes out while
the vehicle is being driven.
*2: The trouble code ª57º, which refers to a low power supply voltage, does not indicate that the ABS control unit is malfunctioning. Do
not replace the ABS control unit with a new one.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONABS
Malfunction Code/Symptom Chart
BR-54

Wheel Sensor or Rotor
DIAGNOSTIC PROCEDURENBBR0102Malfunction code No. 21, 22, 25, 26, 31, 32, 35, 36 or 18
NOTE:
Wheel position should be distinguished by code No. except code
No. 18 (sensor rotor).
1 INSPECTION START
Wheel sensor inspection
SBR485E
©GO TO 2.
2 CHECK CONNECTOR
1. Disconnect connectors from ABS actuator and electric unit and wheel sensor of malfunction code No. Check terminals
for damage or loose connection. Then reconnect connectors.
2. Carry out self-diagnosis again.
Does warning lamp activate again?
Ye s©GO TO 3.
No©INSPECTION END
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
Wheel Sensor or Rotor
BR-56

3 CHECK WHEEL SENSOR ELECTRICAL
1. Disconnect ABS actuator and electric unit connector.
2. Check resistance between ABS actuator and electric unit connector E111 (body side) terminals.
Code No. 21 or 22 (Front RH wheel)
Terminals 4 and 5
Code No. 25 or 26 (Front LH wheel)
Terminals 6 and 7
Code No. 31 or 32 (Rear RH wheel)
Terminals 1 and 2
Code No. 35 or 36 (Rear LH wheel)
Terminals 8 and 9
SBR486E
Resistance:
Front 0.9 - 1.1 kW
Rear 1.44 - 1.76 kW
Is front resistance 0.9 - 1.1 kWand rear resistance 1.44 - 1.76 kW?
Ye s©GO TO 5.
No©GO TO 4.
4 CHECK WHEEL SENSOR
Check each sensor for resistance.
SBR487E
Resistance:
Front 0.9 - 1.1 kW
Rear 1.44 - 1.76 kW
Is front resistance 0.9 - 1.1 kWand rear resistance 1.44 - 1.76 kW?
Ye s©Check the following.
If NG, repair harness or connectors.
IHarness connectors E111, E14, E51, B8, B69
IHarness for open or short between wheel sensor connectors and ABS actuator and
electric unit
No©Replace wheel sensor.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
Wheel Sensor or Rotor (Cont'd)
BR-57

5 CHECK TIRE
Check for inflation pressure, wear and size of each tire. (See NOTE)
Are tire pressure and size correct and is tire wear within specifications?
Ye s©GO TO 6.
No©Adjust tire pressure or replace tire(s). (See NOTE)
6 CHECK WHEEL BEARING
Check wheel bearing axial end play. (See NOTE)
Is wheel bearing axial end play within specifications? Refer to AX-4, ªFront Wheel Bearingº and AX-18, ªRear
Wheel Bearingº.
Ye s©GO TO 7.
No©Check wheel bearing. Refer to AX-4, ªFront Wheel Bearingº and AX-18, ªRear Wheel
Bearingº.
7 CHECK SENSOR ROTOR
Check sensor rotor for teeth damage. (See NOTE)
Is sensor rotor free from damage?
Ye s©Check ABS actuator and electric unit pin terminals for damage or the connection of ABS
actuator and electric unit harness connector. Reconnect ABS actuator and electric unit
harness connector. Then retest.
No©Replace sensor rotor. (See NOTE)
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
Wheel Sensor or Rotor (Cont'd)
BR-58

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.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SYMPTOMSABS
1. ABS Works Frequently
BR-69

2 CHECK MECHANICAL BRAKE SYSTEM PERFORMANCE
Disconnect ABS actuator and electric unit connector and check whether brake is effective.
Does brake system function properly when brake pedal is depressed?
Ye s©GO TO 3.
No©Perform Preliminary Check. Refer to BR-50.
3 CHECK WARNING LAMP INDICATION
Ensure warning lamp remains off while driving.
SBR672E
Is warning lamp turned off?
Ye s©GO TO 4.
No©Carry out self-diagnosis. Refer to BR-41, BR-44.
4 CHECK WHEEL SENSOR
1. Check wheel sensor connector for terminal damage or loose connection.
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©Check ABS actuator and electric unit pin terminals for damage or the connection of ABS
actuator and electric unit harness connector.
Reconnect ABS actuator and electric unit harness connector.
Then retest.
No©Repair.
3. Long Stopping DistanceNBBR0109
1 CHECK MECHANICAL BRAKE SYSTEM PERFORMANCE
Disconnect ABS actuator and electric unit connector and check whether stopping distance is still long.
Does brake system function properly when brake pedal is depressed?
Ye s©Perform Preliminary Check and air bleeding (if necessary).
No©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-70.
TROUBLE DIAGNOSES FOR SYMPTOMSABS
2. Unexpected Pedal Action (Cont'd)
BR-70

=NBBR0079
CAUTION:
Be careful not to damage sensor edge and sensor rotor teeth.
When removing the front or rear wheel hub assembly, discon-
nect the ABS wheel sensor from the assembly and move it
away.
Front Wheel SensorNBBR0079S01
SBR398D
Rear Wheel SensorNBBR0079S02
SBR399D
REMOVAL AND INSTALLATIONABS
BR-80

SBR873C
Front Sensor RotorNBBR0079S03REMOVALNBBR0079S03011. Remove the front wheel hub. Refer to AX-8, ªDisassemblyº.
2. Remove the sensor rotor using suitable puller, drift and bear-
ing replacer.
SBR400DA
INSTALLATIONNBBR0079S0302Install the sensor rotor using suitable drift and press.
IAlways replace sensor rotor with new one.
IPay attention to the direction of front sensor rotor as shown in
figure.
SRA800AA
Rear Sensor RotorNBBR0079S04REMOVALNBBR0079S0401IRemove the sensor rotor using Tool.
SBR402D
INSTALLATIONNBBR0079S0402Install the sensor rotor using suitable drift and press.
IAlways replace sensor rotor with new one.
IPay attention to the direction of front sensor rotor as shown in
figure.
SBR503E
G SensorNBBR0079S06Always replace G sensor if bumped or dropped. Otherwise,
performance characteristics of G sensor will be changed,
which in turn changes ABS control performance characteris-
tics.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
ST
RS
BT
HA
SC
EL
IDX
REMOVAL AND INSTALLATIONABS
Front Sensor Rotor
BR-81