ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C1235/35, C1236/36, C1238/38, C1239/39, C1275/75, C1276/76, C1277/77, C1278/78

DTC Code DTC Name
C1235/35 Foreign Object is Attached on Tip of Front Speed Sensor RH
C1236/36 Foreign Object is Attached on Tip of Front Speed Sensor LH
C1238/38 Foreign Object is Attached on Tip of Rear Speed Sensor RH
C1239/39 Foreign Object is Attached on Tip of Rear Speed Sensor LH
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 speed 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 speed 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 speed sensor tip or speed 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 speed sensor circuit.

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

A01CIC4E20
DTC Code DTC Detection Condition Trouble Area

C1235/35

C1236/36

C1238/38

C1239/39

When either of the following is detected:


  1. At a vehicle speed of 20 km/h (12 mph) or more, noise occurs in the sensor signal from the abnormal wheel for 5 seconds or more.

  2. When the vehicle starts off, the condition that the speed of any wheel is 7 km/h (4.3 mph) or more occurs 3 times or more.

  • Speed sensor

  • Speed sensor rotor

  • Sensor installation

  • Skid control ECU

C1275/75

C1276/76

C1277/77

C1278/78

 Detected only during Test Mode.

  • Speed sensor

  • Speed sensor rotor

Tech Tips


  • DTCs C1235/35 and C1275/75 are for the front speed sensor RH.

  • DTCs C1236/36 and C1276/76 are for the front speed sensor LH.

  • DTCs C1238/38 and C1277/77 are for the rear speed sensor RH.

  • DTCs C1239/39 and C1278/78 are for the rear speed sensor LH.

WIRING DIAGRAM

A01CGUVE01

INSPECTION PROCEDURE

Tech Tips

When C0200/31, C0205/32, C0210/33, and/or C0215/34 is output together with C1235/35, C1236/36, C1238/38, and/or C1239/39, inspect and repair the trouble areas indicated by C0200/31, C0205/32, C0210/33, and/or C0215/34 first Click here for front, or Click here for rear).

PROCEDURE


  1. CHECK SPEED SENSOR AND SPEED SENSOR ROTOR SERRATIONS


    1. A01CHAXE03

      Connect the oscilloscope to each speed sensor terminal of the skid control ECU.

    2. Check that a waveform is output by each sensor circuit when the tires are rotated.

      OK
      The same waveform is output from all the 4 wheels and there is no noise or waveform.

    3. Check that the waveform does not change while jiggling a connector or a wire harness.

      OK
      The waveform does not change.

      Tech Tips


      • As the vehicle speed (wheel revolution speed) increases, a cycle of the waveform narrows and the output voltage becomes greater.


      • When noise is identified in the waveform on the oscilloscope, the erratic signals are generated due to speed sensor rotor's scratches, looseness or foreign matter attached to it.


    NG

    INSPECT EACH SPEED SENSOR Click here

    OK

  2. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTC (See Pub. No. RM1008E, page 05-195).

    3. Start the engine.

    4. Drive the vehicle at the speed of 20 km/h (12 mph) or more for at least 30 seconds.

    5. Check if the same DTC is recorded (See Pub. No. RM1008E, page 05-195).

      Result
      Result Proceed to
      DTCs (C1235/35, C1236/36, C1238/38 and/or C1239/39) are not output A
      DTCs (C1235/35, C1236/36, C1238/38 and/or C1239/39) are output B

    B

    REPLACE SKID CONTROL ECU

    A

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here

  3. INSPECT EACH SPEED SENSOR


    1. A01CHKYE04

      Turn the ignition switch off.

    2. Disconnect each speed sensor connector.

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

      Standard resistance
      for RH
      Tester Connection Condition Specified Condition
      1 (FR+) - 2 (FR-) Always 0.9 to 1.3 kΩ at 20°C (68°F)
      1 (FR+) - Body ground Always 10 kΩ or higher
      2 (FR-) - Body ground Always 10 kΩ or higher
      1 (RR+) - 2 (RR-) Always 1.4 to 1.8 kΩ at 20°C (68°F)
      1 (RR+) - Body ground Always 10 kΩ or higher
      2 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      1 (FL+) - 2 (FL-) Always 0.9 to 1.3 kΩ at 20°C (68°F)
      1 (FL+) - Body ground Always 10 kΩ or higher
      2 (FL-) - Body ground Always 10 kΩ or higher
      1 (RL+) - 2 (RL-) Always 1.4 to 1.8 kΩ at 20°C (68°F)
      1 (RL+) - Body ground Always 10 kΩ or higher
      2 (RL-) - Body ground Always 10 kΩ or higher

      Note

      Check the speed sensor signal after replacement Click here.


    NG

    REPLACE EACH SPEED SENSOR

    OK

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


    1. A01CHUME01

      Disconnect the skid control ECU connectors.

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

      Standard resistance
      for RH
      Tester Connection Condition Specified Condition
      S14-26 (FR+) - A3-1 (FR+) Always Below 1 Ω
      S14-26 (FR+) - Body ground Always 10 kΩ or higher
      S14-25 (FR-) - A3-2 (FR-) Always Below 1 Ω
      S14-25 (FR-) - Body ground Always 10 kΩ or higher
      S13-16 (RR+) - A16-1 (RR+) Always Below 1 Ω
      S13-16 (RR+) - Body ground Always 10 kΩ or higher
      S13-15 (RR-) - A16-2 (RR-) Always Below 1 Ω
      S13-15 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      S14-27 (FL+) - A2-1 (FL+) Always Below 1 Ω
      S14-27 (FL+) - Body ground Always 10 kΩ or higher
      S14-28 (FL-) - A2-2 (FL-) Always Below 1 Ω
      S14-28 (FL-) - Body ground Always 10 kΩ or higher
      S13-22 (RL+) - A15-1 (RL+) Always Below 1 Ω
      S13-22 (RL+) - Body ground Always 10 kΩ or higher
      S13-23 (RL-) - A15-2 (RL-) Always Below 1 Ω
      S13-23 (RL-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. RECONFIRM DTC


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

    2. Clear the DTC (See Pub. No. RM1008E, page 05-195).

    3. Start the engine.

    4. Drive the vehicle at the speed of 20 km/h (12 mph) or more for at least 30 seconds.

    5. Check if the same DTC is recorded (See Pub. No. RM1008E, page 05-195).

      Result
      Result Proceed to
      DTCs (C1235/35, C1236/36, C1238/38 and/or C1239/39) are output A
      DTCs (C1235/35, C1236/36, C1238/38 and/or C1239/39) are not output B

    B

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here

    A

  6. CHECK EACH SPEED SENSOR INSTALLATION


    1. A01CJG2E05

      Turn the ignition switch off.

    2. Check the speed sensor installation.

      OK
      There is no clearance between the sensor and the front steering knuckle (for front) or rear axle carrier (for rear).
      The installation bolt is tightened properly.
      Torque:
      8.0 N*m  { 82 kgf*cm, 71 in.*lbf }

    NG

    INSTALL EACH SPEED SENSOR CORRECTLY

    OK

  7. CHECK EACH SPEED SENSOR TIP


    1. Remove each speed sensor (See Pub. No. RM1008E, page 32-89 for front, or 32-90 for rear).

    2. Check the speed sensor tip.

      OK
      No scratches or foreign matter on the sensor tip.

      Note

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


    NG

    CLEAN OR REPLACE EACH SPEED SENSOR

    OK

  8. CHECK EACH SPEED SENSOR ROTOR


    1. Turn the ignition switch off.

    2. Remove each speed sensor rotor (See Pub. No. RM1008E, page 30-34 for front, or Click here for rear).

    3. Check the speed sensor rotor.

      OK
      No scratches, missing teeth, or foreign matter on the rotors.

      Note

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


    NG

    CLEAN OR REPLACE EACH SPEED SENSOR ROTOR

    OK

  9. RECONFIRM DTC


    1. Install the speed sensor and the speed sensor rotor.

    2. Clear the DTC (See Pub. No. RM1008E, page 05-195).

    3. Start the engine.

    4. Drive the vehicle at the speed of 20 km/h (12 mph) or more for at least 30 seconds.

    5. Check if the same DTC is recorded (See Pub. No. RM1008E, page 05-195).

      Result
      Result Proceed to
      DTCs (C1235/35, C1236/36, C1238/38 and/or C1239/39) are not output A
      DTCs (C1235/35, C1236/36, C1238/38 and/or C1239/39) are output B

    B

    REPLACE SKID CONTROL ECU

    A

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here