o2 sensor NISSAN ALMERA 2001 Service Manual

SEF233G
SEF234G
How to Perform Trouble Diagnoses for Quick
and Accurate Repair
NJBR0094INTRODUCTIONNJBR0094S01The ABS system has an electronic control unit to control major
functions. The control unit accepts input signals from sensors and
instantly drives actuator. It is essential that both kinds of signals are
proper and stable. It is also important to check for conventional
problems: such as air leaks in the booster or lines, lack of brake
fluid, or other problems with the brake system.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electric connections or faulty wiring. In this case,
careful checking of suspicious circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems, so a
road test should be performed.
Before undertaking actual checks, take just a few minutes to talk
with a customer who approaches with a ABS complaint. The cus-
tomer is a very good source of information on such problems;
especially intermittent ones. Through the talks with the customer,
find out what symptoms are present and under what conditions
they occur.
Start your diagnosis by looking for ªconventionalº problems first.
This is one of the best ways to troubleshoot brake problems on an
ABS controlled vehicle. Also check related Service Bulletins for
information.
TROUBLE DIAGNOSIS Ð INTRODUCTIONABS
How to Perform Trouble Diagnoses for Quick and Accurate Repair
BR-71

Malfunction Code/Symptom ChartNJBR0097MODELS WITH SELF-DIAGNOSIS FUNCTION (DATA
LINK CONNECTOR TERMINAL NO. 9)
NJBR0097S01
Code No. (No. of LED flashes) Malfunctioning part Reference page
12 Self-diagnosis could not detect any malfunctions. Ð
18 Sensor rotor BR-78
21 Front right sensor (open-circuit) BR-78
22 Front right sensor (short-circuit) BR-78
25 Front left sensor (open-circuit) BR-78
26 Front left sensor (short-circuit) BR-78
31 Rear right sensor (open-circuit) BR-78
32 Rear right sensor (short-circuit) BR-78
35 Rear left sensor (open-circuit) BR-78
36 Rear left sensor (short-circuit) BR-78
41 Actuator front right outlet solenoid valve BR-81
42 Actuator front right inlet solenoid valve BR-81
45 Actuator front left outlet solenoid valve BR-81
46 Actuator front left inlet solenoid valve BR-81
51 Actuator rear right outlet solenoid valve BR-81
52 Actuator rear right inlet solenoid valve BR-81
55 Actuator rear left outlet solenoid valve BR-81
56 Actuator rear left inlet solenoid valve BR-81
57* Power supply (Low voltage) BR-86
61 Actuator motor or motor relay BR-84
63 Solenoid valve relay BR-81
71 Control unit BR-88
ABS 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-95
ABS warning lamp stays on, during
self-diagnosis.Control unit Ð
ABS warning lamp does not come on
when ignition switch is turned on.Fuse, warning lamp bulb or warning lamp circuit
Control unitBR-93
ABS warning lamp does not come on
during self-diagnosis.Control unit Ð
Pedal vibration and noise Ð BR-92
Long stopping distance Ð BR-90
Unexpected pedal action Ð BR-89
ABS does not work. Ð BR-91
ABS works frequently. Ð BR-89
*: Under voltage that is too low, the control unit disable the ABS. It does not set the ABS in fail-safe condition. Instead, the ABS becomes
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONABS
Malfunction Code/Symptom Chart
BR-76

Wheel Sensor or RotorNJBR0098DIAGNOSTIC PROCEDURENJBR0098S01(Malfunction code No. 21, 22, 25, 26, 31, 32, 35, 36 or 18 for
models with self-diagnosis function)
NOTE:
Wheel position should be identified by code No. except code No.
18 (sensor rotor).
1 INSPECTION START
Wheel sensor inspection
SBR476EB
©GO TO 2.
2 CHECK CONNECTOR
1. Disconnect connectors from control unit and wheel sensor of malfunction code No. Check terminals for damage or
loose connections. 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-78

3 CHECK WHEEL SENSOR CIRCUIT
1. Disconnect control unit connector.
2. Check resistance between control unit connector 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 3
Code No. 35 or 36 (Rear LH wheel)
Terminals 8 and 9
Resistance: 1.44 - 1.76 kW
SBR477EC
Is resistance 1.44 - 1.76 kW?
Ye s©GO TO 5.
No©GO TO 4.
4 CHECK WHEEL SENSOR
Check resistance of each sensor. (See NOTE.)
Resistance: 1.44 - 1.76 kW
SBR478EC
Is resistance 1.44 - 1.76 kW?
Ye s©Repair harness and connectors between control unit connector and wheel sensor con-
nector.
No©Replace wheel sensor.
5 CHECK TIRE
Check for inflation pressure, wear and size of each tire.
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).
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
Wheel Sensor or Rotor (Cont'd)
BR-79

6 CHECK WHEEL BEARING
Check wheel bearing axial end play.
Check clearance between sensor and rotor.
Clearance:
Front
0.7 - 1.8 mm (0.028 - 0.071 in)
Rear
0.4 - 1.5 mm (0.016 - 0.059 in)
SBR333E
SBR069CA
Is axial end play and clearance within specifications?
Ye s©GO TO 7.
No©Clean sensor fixing portion, or replace sensor.
7 CHECK SENSOR ROTOR
Check sensor rotor for teeth damage.
Is sensor rotor free from damage?
Ye s©Check control unit pin terminals for damage or the connection of control unit harness
connector. Reconnect control unit harness connector. Then retest.
No©Replace sensor rotor.
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC ITEMSABS
Wheel Sensor or Rotor (Cont'd)
BR-80

1. ABS Works FrequentlyNJBR0104
1 CHECK BRAKE FLUID PRESSURE
Check brake fluid pressure distribution.
Is brake fluid pressure distribution normal?
Ye s©GO TO 2.
No©Perform Preliminary Check. Refer to BR-72.
2 CHECK WHEEL SENSOR
1. Check wheel sensor connector for terminal damage or loose connections.
2. Perform wheel sensor mechanical check.
Refer to ªWheel Sensor or Rotorº, BR-78.
Are wheel sensors functioning properly?
Ye s©GO TO 3.
No©Repair.
3 CHECK FRONT AXLE
Check front and rear axles for excessive looseness. Refer to AX section, ªFront Wheel Bearingº, ªON-VEHICLE SERVICEº
and ªRear Wheel Bearingº, ªON-VEHICLE SERVICEº.
Is front axle installed properly?
Ye s©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-89.
No©Repair.
2. Unexpected Pedal ActionNJBR0105
1 CHECK BRAKE PEDAL STROKE
Check brake pedal stroke. Is stroke excessively large?
SBR540A
Ye s©Perform Preliminary Check. Refer to BR-72.
No©GO TO 2.
TROUBLE DIAGNOSES FOR SYMPTOMSABS
1. ABS Works Frequently
BR-89

2 CHECK CONNECTOR AND PERFORMANCE
1. Disconnect ABS actuator and electric unit connector.
2. Check whether brake is effective.
OK or NG
Ye s©GO TO 3.
No©Perform Preliminary Check. Refer to BR-72.
3 CHECK WARNING LAMP INDICATION
Ensure warning lamp remains off while driving.
SBR759E
Is warning lamp turned off?
Ye s©GO TO 4.
No©Carry out self-diagnosis. Refer to BR-63, BR-65.
4 CHECK WHEEL SENSOR
1. Check wheel sensor connector for terminal damage or loose connection.
2. Perform wheel sensor mechanical check.
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 DistanceNJBR0106
1 CHECK CONNECTOR AND PERFORMANCE
1. Cancel ABS by disconnecting ABS actuator and electric unit connector.
2. Check whether stopping distance is still long.
OK or NG
OK©Perform Preliminary Check and air bleeding.
NG©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-89.
TROUBLE DIAGNOSES FOR SYMPTOMSABS
2. Unexpected Pedal Action (Cont'd)
BR-90

5. Pedal Vibration and Noise=NJBR0108
1 INSPECTION START
Pedal vibration and noise inspection
SAT797A
©GO TO 2.
2 CHECK SYMPTOM
1. Apply brake.
2. Start engine.
Does the symptom appear only when engine is started?
Ye s©Carry out self-diagnosis. Refer to BR-63, BR-65.
No©GO TO 3.
3 RECHECK SYMPTOM
Does the symptom appear when electrical equipment switches (such as headlamp) are operated?
Ye s©GO TO 4.
No©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-89.
4 CHECK WHEEL SENSOR
Check wheel sensor shield ground. For location of shield ground, refer to wiring diagram and ªHARNESS LAYOUTº in EL
section.
Is wheel sensor shield grounded properly?
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.
NOTE:
ABS may operate and cause vibration under any of the following
conditions.
+Applying brake gradually when shifting or operating clutch.
+Low friction (slippery) road.
+High speed cornering.
+Driving over bumps and pot holes.
+Engine speed is over 5,000 rpm with vehicle stopped.
TROUBLE DIAGNOSES FOR SYMPTOMSABS
5. Pedal Vibration and Noise
BR-92

NJBR0111
CAUTION:
Be careful not to damage sensor edge and sensor rotor teeth.
When removing the front or rear wheel hub assembly, first
remove the ABS wheel sensor from the assembly. Failure to
do so may result in damage to the sensor wires making the
sensor inoperative.
Wheel SensorsNJBR0111S01
SBR902D
REMOVAL AND INSTALLATIONABS
BR-97

SBR984C
SBR873CA
Sensor RotorNJBR0111S02REMOVALNJBR0111S02011. Remove the drive shaft and rear wheel hub. Refer to ªDrive
Shaftº and ªWheel Hubº in AX section.
2. Remove the sensor rotor using suitable puller, drift and bear-
ing replacer.
SBR985C
INSTALLATIONNJBR0111S0202Install the sensor rotor. For front sensor rotor, use hammer and
wooden block. For rear sensor rotor, use suitable drift and press.
+Always replace sensor rotor with new one.
SBR986C
+Pay attention to the dimension of rear sensor rotor as show in
figure.
h: 17.7 - 18.7 mm (0.697 - 0.736 in)
REMOVAL AND INSTALLATIONABS
Sensor Rotor
BR-99