C1277
C1235, C1236, C1238, C1239, C1275, C1276, C1277, C1278Description
The wheel sensors detect wheel speed and transmit the signals to the ECU. These signals are used for control of the ABS control system. Each of the front and rear rotors has 48 serrations.
When the rotors rotate, the magnetic field generated by the permanent magnet in the wheel sensor induces an AC voltage.
Since the frequency of this AC voltage changes in direct proportion to the speed of the rotor, the frequency is used by the ECU to detect the speed of each wheel.
When foreign matter adheres to the wheel sensor tip or wheel sensor rotor, or the rotor teeth are chipped, these DTCs are output. An abnormal waveform input from the sensor determines these conditions.
These DTCs may be detected when a malfunction occurs in the connector terminals or wire harness of the wheel sensor circuit.
DTCs C1275 to C1278 can be deleted when the wheel sensor sends a wheel speed signal or the Test Mode ends. DTCs from C1275 to C1278 are output only in the Test Mode.
DTC Logic:
NOTE:
^ DTCs C1235 and C1275 are for the front wheel sensor RH.
^ DTCs C1236 and C1276 are for the front wheel sensor LH.
^ DTCs C1238 and C1277 are for the rear wheel sensor RH.
^ DTCs C1239 and C1278 are for the rear wheel sensor LH.
Diagnosis Procedure
CAUTION:
When replacing the brake ECU, perform initialization of linear solenoid valve and calibration.
NOTE:
When C0200, C0205, C0210, or C0215 is output together with C1235, C1236, C1238, or C1239, inspect and repair the trouble areas indicated by C0200, C0205, C0210, or C0215 first.
1.RECONFIRM DTC
1. Turn the ignition switch OFF.
2. Clear the DTC.
3. Turn the ignition switch ON (READY).
4. Drive the vehicle at the speed of 20 km/h (12 MPH) or more for at least 60 seconds.
5. Check if the same DTC is recorded.
Result:
A >> GO TO 2.
B >> Replace brake ECU.
2.INSPECT EACH WHEEL SENSOR
1. Turn the ignition switch OFF.
2. Disconnect each wheel sensor connector E41 (Front RH), E19 (Front LH), B43 (Rear).
3. Measure the resistance according to the value(s) in the table below.
RH:
LH:
Result:
Is the inspection result normal?
A >> GO TO 3.
B >> GO TO 4.
C >> Replace each wheel sensor.
3.CHECK HARNESS AND CONNECTOR (BRAKE CONTROL SENSOR WIRE)
1. Disconnect the brake control sensor wire.
2. Measure the resistance according to the value(s) in the table below.
RH:
LH:
CAUTION:
Check the wheel sensor signal after replacement.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace skid control sensor wire.
4.CHECK HARNESS AND CONNECTOR (BRAKE ECU - EACH WHEEL SENSOR)
1. Disconnect the brake ECU connectors.
2. Measure the resistance according to the value(s) in the table below.
RH:
LH:
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace harness or connector.
5.RECONFIRM DTC
1. Reconnect the skid control sensor wire.
2. Reconnect the brake ECU connectors and the wheel sensor connector.
3. Clear the DTC.
4. Turn the ignition switch ON (READY).
5. Drive the vehicle at the speed of 20 km/h (12 MPH) or more for at least 60 seconds.
6. Check if the same DTC is recorded.
Result:
A >> GO TO 6.
B >> GO TO 7.
C >> Check for intermittent problems (symptom simulation).
6.CHECK FRONT WHEEL SENSOR TIP
1. Turn the ignition switch OFF.
2. Remove the front wheel sensor.
3. Check the wheel sensor tip.
NOTE:
^ No scratches or foreign matter on the sensor tip.
^ Check the wheel sensor signal after cleaning or replacement.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Clean or replace front wheel sensor.
7.CHECK EACH WHEEL SENSOR ROTOR
1. Turn the ignition switch OFF.
2. Remove each wheel sensor rotor.
3. Check the wheel sensor rotor.
NOTE:
^ No scratches, missing teeth or foreign matter on the rotors.
^ Check the wheel sensor signal after cleaning or replacement.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Clean or replace each wheel sensor rotor.
8.RECONFIRM DTC
1. Install the front wheel sensor and the wheel sensor rotor.
2. Clear the DTC.
3. Turn the ignition switch ON (READY).
4. Drive the vehicle at the speed of 20 km/h (12 MPH) or more for at least 60 seconds.
5. Check if the same DTC is recorded.
Result:
A >> Check for intermittent problems (symptom simulation).
B >> Replace brake ECU.
Special Repair Requirement
1.ZERO ADJUSTMENT FOR EACH SENSOR AND OFFSET LEANING FOR LINEAR SOLENOID VALVE
After erasing brake ECU memories, perform zero adjustment of following sensors and initialization of linear solenoid valve.
^ Steering angle sensor: BRC-9, "PERFORM ZERO POINT OF STEERING ANGLE SENSOR: Description". Testing and Inspection
^ Yaw rate/side/decel G sensor: BRC-8, "PERFORM ZERO POINT OF YAW RATE/SIDE/DECEL G SENSOR: Description". Testing and Inspection
^ Brake stroke sensor: BRC-9, "PERFORM ADJUSTMENT OF STROKE SENSOR: Description".Perform Adjustment of Stroke Sensor
^ Linear solenoid valve: BRC-7, "PERFORM INITIALIZATION OF LINEAR SOLENOID VALVE AND CALIBRATION: Description". Perform Initialization of Linear Solenoid Valve and Calibration
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