VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1237/37, C1275/75, C1276/76, C1277/77, C1278/78

DTC Code DTC Name
C1237/37 Speed Sensor Rotor Faulty
C1275/75 Abnormal Change in Output Signal of Front Speed Sensor RH (Test Mode DTC)
C1276/76 Abnormal Change in Output Signal of Front Speed Sensor LH (Test Mode DTC)
C1277/77 Abnormal Change in Output Signal of Rear Speed Sensor RH (Test Mode DTC)
C1278/78 Abnormal Change in Output Signal of Rear Speed Sensor LH (Test Mode DTC)

DESCRIPTION

The skid control ECU measures the speed of each wheel by receiving signals from the speed sensor.

These signals are used for recognizing that all four wheels are operating properly.

Therefore, all wheel signals must be equal.

DTCs C1275/75 to C1278/78 will be cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs C1275/75 to C1278/78 are output only in Test Mode.

A01ELUJE04
DTC Code DTC Detection Condition Trouble Area
C1237/37

Any of the following is detected:


  1. Discrepancy among four wheel speed sensor output.

  2. Abnormal pulse signals from 3 or more sensors.

  3. Continuous ABS control is performed on at least 2 wheels for 60 seconds or more.

  • Tire and wheel size

  • Tire deformation

  • Speed sensor rotor

  • Speed sensor

  • Speed sensor circuit

  • Brake actuator assembly (Skid control ECU)

C1275/75

C1276/76

C1277/77

C1278/78

 Detected only during Test Mode Speed sensor rotor

Tech Tips


  • DTC C1275/75 is for the front speed sensor RH.

  • DTC C1276/76 is for the front speed sensor LH.

  • DTC C1277/77 is for the rear speed sensor RH.

  • DTC C1278/78 is for the rear speed sensor LH.

WIRING DIAGRAM

Refer to DTCs C0200/31, C0205/32, C0210/33, C0215/34, C1330/35, C1331/36, C1332/38 and C1333/39 Click here for front, or Click here for rear).

INSPECTION PROCEDURE

Tech Tips

When C0200/31, C0205/32, C0210/33, C0215/34, C1330/35, C1331/36, C1332/38 and/or C1333/39 is output together with C1237/37, inspect and repair the trouble areas indicated by C0200/31, C0205/32, C0210/33, C0215/34, C1330/35, C1331/36, C1332/38 and/or C1333/39 first Click here for front, or Click here for rear).

PROCEDURE


  1. CHECK TIRES


    1. Check the size and condition of all four wheels Click here.

      Tech Tips

      The DTC is output when tire deformation or a difference in tire size is detected.

      OK
      The diameter of all four tires and air pressure are the same.
      Result
      Result Proceed to
      OK (except for rear 2WD) A
      OK (for rear 2WD) B
      NG C

    B

    CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE) Click here

    C

    REPLACE TIRES SO THAT ALL FOUR TIRES ARE THE SAME SIZE

    A

  2. CHECK SPEED SENSOR AND SPEED SENSOR ROTOR


    1. Remove the speed sensor and speed sensor rotor Click here for front, or Click here for rear).

    2. Check the speed sensor tip and speed sensor rotor.

      OK
      No scratches, oil, or foreign matter on the sensor tip and rotor.

      Note

      Check the speed sensor signal after cleaning or replacement Click here.


    NG

    CLEAN OR REPLACE SPEED SENSOR OR SPEED SENSOR ROTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - SPEED SENSOR)


    1. A01EK6ZE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Brake Actuator (Skid Control ECU))
      *2

      Front view of wire harness connector

      (to Front Speed Sensor)
      *3

      Front view of wire harness connector

      (to Rear Speed Sensor)

      Install the speed sensor and speed sensor rotor.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    3. Disconnect the skid control ECU connector and the speed sensor connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      A42-9 (FR+) - A26-1 (FR+) Always Below 1 Ω
      A42-9 (FR+) - Body ground Always 10 kΩ or higher
      A42-10 (FR-) - A26-2 (FR-) Always Below 1 Ω
      A42-10 (FR-) - Body ground Always 10 kΩ or higher
      A42-8 (RR+) - M13-1 (RR+) Always Below 1 Ω
      A42-8 (RR+) - Body ground Always 10 kΩ or higher
      A42-29 (RR-) - M13-2 (RR-) Always Below 1 Ω
      A42-29 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A42-26 (FL+) - A27-1 (FL+) Always Below 1 Ω
      A42-26 (FL+) - Body ground Always 10 kΩ or higher
      A42-5 (FL-) - A27-2 (FL-) Always Below 1 Ω
      A42-5 (FL-) - Body ground Always 10 kΩ or higher
      A42-6 (RL+) - L18-1 (RL+) Always Below 1 Ω
      A42-6 (RL+) - Body ground Always 10 kΩ or higher
      A42-27 (RL-) - L18-2 (RL-) Always Below 1 Ω
      A42-27 (RL-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. RECONFIRM DTC


    1. Reconnect the skid control ECU connector and the speed sensor connector.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1237/37) is output A
      DTC (C1237/37) is not output B

    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  5. REPLACE SPEED SENSOR


    1. Turn the ignition switch off.

    2. Replace the speed sensor Click here for front, or Click here for rear).

      Note

      Check the speed sensor signal after replacement Click here.


    NEXT

  6. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Start the engine.

    3. Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.

    4. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1237/37) is output A
      DTC (C1237/37) is not output B

    B

    END

    A

  7. REPLACE SPEED SENSOR ROTOR


    1. Turn the ignition switch off.

    2. Remove the drive shaft assembly Click here for front, or Click here for rear).

    3. Replace the drive outboard joint shaft assembly (speed sensor rotor) Click here for front, or Click here for rear).

      Tech Tips

      If the speed sensor rotor needs to be replaced, replace it together with the drive outboard joint shaft assembly.

      Note

      Check the speed sensor signal after replacement Click here.


    NEXT

  8. RECONFIRM DTC


    1. Install the drive shaft assembly.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1237/37) is output A
      DTC (C1237/37) is not output B

    B

    END

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  9. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)


    1. A01EKR8E09
      Text in Illustration
      *1 Front view of skid control sensor wire
      *2 for RH
      *3 for LH
      *4

      Front view of wire harness connector

      (to Sensor Side Connector "A")
      *5

      Front view of wire harness connector

      (to Vehicle Side Connector "B")

      Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    2. Disconnect the skid control sensor wire.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      M13 ("A"-2) - M13 ("B"-1) Always Below 1 Ω
      M13 ("A"-2) - M13 ("B"-2) Always 10 kΩ or higher
      M13 ("A"-2) - Body ground Always 10 kΩ or higher
      M13 ("A"-1) - M13 ("B"-2) Always Below 1 Ω
      M13 ("A"-1) - M13 ("B"-1) Always 10 kΩ or higher
      M13 ("A"-1) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      L18 ("A"-2) - L18 ("B"-1) Always Below 1 Ω
      L18 ("A"-2) - L18 ("B"-2) Always 10 kΩ or higher
      L18 ("A"-2) - Body ground Always 10 kΩ or higher
      L18 ("A"-1) - L18 ("B"-2) Always Below 1 Ω
      L18 ("A"-1) - L18 ("B"-1) Always 10 kΩ or higher
      L18 ("A"-1) - Body ground Always 10 kΩ or higher

      Note

      Check the speed sensor signal after replacement Click here.


    NG

    REPLACE SKID CONTROL SENSOR WIRE Click here

    OK

  10. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR)


    1. A01EJF5E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Brake Actuator (Skid Control ECU))
      *2

      Front view of wire harness connector

      (to Rear Speed Sensor)

      Reconnect the skid control sensor wire.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    3. Disconnect the skid control ECU connector and the rear speed sensor connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      A42-8 (RR+) - M13-1 (RR+) Always Below 1 Ω
      A42-8 (RR+) - Body ground Always 10 kΩ or higher
      A42-29 (RR-) - M13-2 (RR-) Always Below 1 Ω
      A42-29 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A42-6 (RL+) - L18-1 (RL+) Always Below 1 Ω
      A42-6 (RL+) - Body ground Always 10 kΩ or higher
      A42-27 (RL-) - L18-2 (RL-) Always Below 1 Ω
      A42-27 (RL-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. RECONFIRM DTC


    1. Reconnect the skid control ECU connector and the rear speed sensor connector.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1237/37) is output A
      DTC (C1237/37) is not output B

    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  12. REPLACE REAR SPEED SENSOR AND REAR SPEED SENSOR ROTOR


    1. Turn the ignition switch off.

    2. Replace the rear speed sensor and the rear axle hub and bearing assembly (rear speed sensor rotor) Click here.

      Tech Tips

      The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly.

      If the rear speed sensor rotor needs to be replaced, replace it together with the rear axle hub and bearing assembly with rear speed sensor.

      Note

      Check the speed sensor signal after replacement Click here.


    NEXT

  13. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Start the engine.

    3. Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.

    4. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1237/37) is output A
      DTC (C1237/37) is not output B

    B

    END

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here