ANTI-LOCK BRAKE SYSTEM(for Type B), Diagnostic DTC:C1401 and C1402

DTC Code DTC Name
C1401 Front Speed Sensor RH Malfunction
C1402 Front Speed Sensor LH Malfunction

DESCRIPTION

Refer to DTCs C1413 and C1414.

Click here

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1401

Front Speed Sensor RH Malfunction

Any of the following conditions is detected:

  1. At a vehicle speed of 10 km/h (6 mph) or more, output voltage from one of the speed sensors is less than that from the other sensors for 15 seconds or more.

  2. At a vehicle speed less than 10 km/h (6 mph), output from one of the speed sensors is 0 km/h (0 mph) for 1 second or more.

  3. At a vehicle speed of 10 km/h (6 mph) or more, outputs from both front speed sensors are 0 km/h (0 mph) for 15 seconds or more.

  • Front speed sensor RH

  • Sensor installation

  • Front speed sensor rotor RH (Front axle hub sub-assembly RH)

C1402

Front Speed Sensor LH Malfunction

Any of the following conditions is detected:

  1. At a vehicle speed of 10 km/h (6 mph) or more, output voltage from one of the speed sensors is less than that from the other sensors for 15 seconds or more.

  2. At a vehicle speed less than 10 km/h (6 mph), output from one of the speed sensors is 0 km/h (0 mph) for 1 second or more.

  3. At a vehicle speed of 10 km/h (6 mph) or more, outputs from both front speed sensors are 0 km/h (0 mph) for 15 seconds or more.

  • Front speed sensor LH

  • Sensor installation

  • Front speed sensor rotor LH (Front axle hub sub-assembly LH)

Tip:

Even after the trouble areas are repaired, the ABS warning light will not go off unless the following operations are performed:

  1. Drive the vehicle at 20 km/h (12 mph) for 30 seconds or more and check that the ABS warning light goes off.

  2. Clear the DTCs.

Tip:
  • DTC C1401 is for the front speed sensor RH.

  • DTC C1402 is for the front speed sensor LH.

PROCEDURE

  1. CHECK FRONT SPEED SENSOR INSTALLATION

    1. C168336C10

      *1

      Front Speed Sensor

      *a

      Correct

      *b

      Incorrect

      *c

      8.5 Nm

      *d

      No clearance

      Check the speed sensor installation.

      OK

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

      The installation bolt is tightened properly.

      Torque

      8.5 N*m (87 kgf*cm, 75 in.*lbf)

    Result

    Proceed to

    OK

    NG

    NG

    INSTALL FRONT SPEED SENSOR CORRECTLY

    OK
  2. CHECK FRONT SPEED SENSOR AND SENSOR ROTOR

    1. Remove the front speed sensor and the component with the sensor rotor.

      for speed sensor:Click here

      for sensor rotor:Click here

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

      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

    Result

    Proceed to

    OK

    NG

    NG

    CLEAN OR REPLACE FRONT SPEED SENSOR OR COMPONENT WITH SENSOR ROTOR

    OK
  3. READ VALUE USING GTS (FRONT SPEED SENSOR)

    1. Install the front speed sensor and the component with the sensor rotor.

    2. Connect the GTS to the DLC3.

    3. Start the engine.

    4. Select the Data List using the GTS.

      Click here

      Chassis > ABS/VSC/TRC > Data List

      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

      Chassis > ABS/VSC/TRC > Data List

      Tester Display

      FR Wheel Speed

      FL Wheel Speed

    5. Check the speed value output from the speed sensor displayed on the GTS.

      Tip:

      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 hereClick here

      OK

      The speed value output from the speed sensor displayed on the GTS is similar to the speed indicated on the speedometer.

    Result

    Proceed to

    OK

    NG

    OK

    USE SIMULATION METHOD TO CHECK

    NG
  4. 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

    Result

    Proceed to

    NEXT

    NEXT
  5. RECONFIRM DTC

    1. Clear the DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the ignition switch off.

    3. Start the engine.

    4. Perform a road test.

    5. Check if the same DTC is output.

      Click here

      Chassis > ABS/VSC/TRC > Trouble Codes

      Result

      Result

      Proceed to

      DTCs C1401 and C1402 are not output.

      A

      DTCs C1401 and/or C1402 are output.

      B

      Note:

      Check the speed sensor signal after replacement.

      Click here

      Tip:
      • If the front speed sensor rotor needs to be replaced, replace the front axle hub sub-assembly.

      • 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

    A

    END

    B

    REPLACE FRONT AXLE HUB SUB-ASSEMBLY