ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C1271, C1272, C1330, C1331, C1464, C1465

DTC Code DTC Name
C1271 Low Output Signal of Front Speed Sensor RH (Test Mode DTC)
C1272 Low Output Signal of Front Speed Sensor LH (Test Mode DTC)
C1330 Open in Front Speed Sensor RH
C1331 Open in Front Speed Sensor LH
C1464 Front Speed Sensor RH
C1465 Front Speed Sensor LH

DESCRIPTION

Each speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU (brake actuator assembly). These signals are used by the ABS control system.

Speed sensor rotors have rows of alternating N and S magnetic poles, with 32 pairs per wheel, and their magnetic fields change when the rotors turn.

Hall IC type speed sensors use the frequency of output pulses to detect the vehicle speed. Because the sensor outputs digital pulses, it can detect the vehicle speed even when the vehicle is nearly stationary.

DTCs C1271 and C1272 are cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs C1271 and C1272 are output only in Test Mode.

A0138FEE10
DTC No. DTC Detection Condition Trouble Area

C1464

C1465

Any of the following is detected:


  1. The vehicle speed is more than 50.4 km/h (31 mph) and pulses are not input for 0.4 seconds.

  2. After the initial start or restart and when the vehicle speed has reached 12 km/h (7 mph), the wheel speed of 0 km/h (0 mph) is detected.

  3. After the initial start or restart and when the vehicle speed has reached 20 km/h (12 mph), a front wheel speed of 0 km/h (0 mph) is detected.

  4. The following conditions are met for 9 to 72 seconds or more (varies depending on the driving conditions):


    • The difference between the speed of the fastest wheel and the speed of the slowest wheel is 5% or more of vehicle speed.*1

    • The vehicle speed is less than 100 km/h (62 mph) and the difference between the speed of the fastest wheel and the speed of the slowest wheel is 5 km/h (3 mph) or more.*2

    • The vehicle speed is 100 km/h (62 mph) or more and the difference between the speed of the fastest wheel and the speed of the slowest wheel is 6% or more of vehicle speed.*1

  5. Wheel speed sensor signal fluctuation is equivalent to 98 G or more, or alternates between 50 G or more and -50 G or less.

  6. An abnormal signal is received from a wheel speed sensor.

  • Front speed sensor RH/LH

  • Speed sensor circuit

  • Front speed sensor rotor RH/LH (Front axle hub bearing RH/LH)

  • Front speed sensor RH/LH installation

  • Skid control ECU (Brake actuator assembly)

C1330

C1331

 An open or short in the speed sensor signal circuit.

  • Front speed sensor RH/LH

  • Speed sensor circuit

  • Front speed sensor RH/LH installation

C1271

C1272

 Detected only during Test Mode.

  • Front speed sensor RH/LH

  • Front speed sensor RH/LH installation

  • Front speed sensor rotor RH/LH (Front axle hub bearing RH/LH)

*1: If the speed of any wheel is less than 5 km/h (3 mph), a speed difference of up to 15% is allowable.

*2: If the speed of any wheel is less than 5 km/h (3 mph), a speed difference of up to 16 km/h (10 mph) is allowable.

Tech Tips


  • DTCs C1271, C1330 and C1464 are for the front speed sensor RH.

  • DTCs C1272, C1331 and C1465 are for the front speed sensor LH.

WIRING DIAGRAM

A0137XPE04

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (FRONT SPEED SENSOR)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

    5. According to the display on the intelligent tester, read the Data List.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      FR Wheel Speed Front wheel speed sensor RH reading / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph) Vehicle stopped: 0 km/h (0 mph) When driving at constant speed: No large fluctuations
      FL Wheel Speed Front wheel speed sensor LH reading / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph) Vehicle stopped: 0 km/h (0 mph) When driving at constant speed: No large fluctuations

    6. Check the speed value output from the speed sensor displayed on the intelligent tester.

      Tech Tips

      Factors that affect the indicated vehicle speed include tire size, tire pressure, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using a speedometer tester (calibrated chassis dynamometer). For details about testing and the margin of error, see the reference chart Click here.

      OK
      The speed value output from the speed sensor displayed on the intelligent tester is similar to the speed indicated on the speedometer.

    NG

    CHECK FRONT SPEED SENSOR INSTALLATION Click here

    OK

  2. PERFORM TEST MODE INSPECTION (SIGNAL CHECK)


    1. Turn the ignition switch off.

    2. Perform the sensor check using the Test Mode procedure Click here.

      OK
      All Test Mode DTCs are not output.

    NG

    CHECK FRONT SPEED SENSOR INSTALLATION Click here

    OK

  3. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off.

    4. Start the engine.

    5. Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.

    6. Check if the same DTC is output Click here.

      Result
      Result Proceed to
      DTCs C1330, C1331, C1464 and C1465 are not output. A
      DTCs C1330, C1331, C1464 and/or C1465 are output. B

    B

    Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS

  4. CHECK FRONT SPEED SENSOR INSTALLATION


    1. A0136E1E03
      Text in Illustration
      *1 Front Speed Sensor
      *a No clearance
      *b OK
      *c NG

      Turn the ignition switch off.

    2. Check the front speed sensor installation.

      OK
      There is no clearance between the sensor and the front steering knuckle.

    NG

    INSTALL FRONT SPEED SENSOR CORRECTLY Click here

    OK

  5. CHECK FRONT SPEED SENSOR AND FRONT SPEED SENSOR ROTOR


    1. Remove the front speed sensor and the front speed sensor rotor (front axle hub bearing) Click here for front speed sensor, and Click here for front speed sensor rotor (front axle hub bearing)).

    2. Check the front speed sensor tip and front speed sensor rotor (front axle hub bearing).

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

      Note


      • If no damage to the speed sensor tip is found during this inspection, do not replace the speed sensor.

        If there are any ferrous metal filings stuck to the rotor, this will result in a malfunction, so confirm that the rotor is not contaminated with foreign matter before replacing the sensor.

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


    NG

    CLEAN OR REPLACE FRONT SPEED SENSOR OR FRONT SPEED SENSOR ROTOR

    OK

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


    1. Install the front speed sensor and the front speed sensor rotor (front axle hub bearing).

    2. Disconnect the A46 skid control ECU (brake actuator assembly) connector and the A7 and/or A13 front speed sensor connector.

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

      Standard Resistance
      RH
      Tester Connection Condition Specified Condition
      A46-16 (FR+) - A7-1 (FR+) Always Below 1 Ω
      A46-16 (FR+) - Body ground Always 10 kΩ or higher
      A46-4 (FR-) - A7-2 (FR-) Always Below 1 Ω
      A46-4 (FR-) - Body ground Always 10 kΩ or higher
      LH
      Tester Connection Condition Specified Condition
      A46-19 (FL+) - A13-1 (FL+) Always Below 1 Ω
      A46-19 (FL+) - Body ground Always 10 kΩ or higher
      A46-8 (FL-) - A13-2 (FL-) Always Below 1 Ω
      A46-8 (FL-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. RECONFIRM DTC


    1. Reconnect the skid control ECU (brake actuator assembly) connector and the front speed sensor connector.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off.

    4. Start the engine.

    5. Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.

    6. Check if the same DTC is output Click here.

      Result
      Result Proceed to
      DTCs C1330, C1331, C1464 and/or C1465 are output. A
      DTCs C1330, C1331, C1464 and C1465 are not output. B

    B

    CHECK FOR INTERMITTENT PROBLEMS

    A

  8. REPLACE FRONT SPEED SENSOR


    1. Turn the ignition switch off.

    2. Replace the front speed sensor Click here.

      Note

      Check the speed sensor signal after replacement Click here.


    NEXT

  9. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Turn the ignition switch off.

    3. Start the engine.

    4. Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.

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

      Result
      Result Proceed to
      DTCs C1330, C1331, C1464 and/or C1465 are output. A
      DTCs C1330, C1331, C1464 and C1465 are not output. B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Click here.


    B

    END

    A

  10. REPLACE FRONT AXLE HUB BEARING


    1. Turn the ignition switch off.

    2. Replace the front speed sensor rotor (front axle hub bearing) Click here.

      Tech Tips

      If the front speed sensor rotor needs to be replaced, replace the front axle hub bearing.

      Note

      Check the speed sensor signal after replacement Click here.


    NEXT

  11. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Turn the ignition switch off.

    3. Start the engine.

    4. Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.

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

      Result
      Result Proceed to
      DTCs C1330, C1331, C1464 and C1465 are not output. A
      DTCs C1330, C1331, C1464 and/or C1465 are output. B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Click here.


    B

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    A

    END