VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1405, C1406

DTC Code DTC Name
C1405 Open or Short in Front Speed Sensor RH Circuit
C1406 Open or Short in Front Speed Sensor LH Circuit

DESCRIPTION

Refer to DTCs C1401 and C1402 Click here.

DTC NO. DTC Detection Condition Trouble Area

C1405

C1406

Either of the following is detected:


  1. An open in the speed sensor signal circuit continues for 0.5 seconds or more.

  2. With the IG1 terminal voltage 9.5 V or more, the sensor power supply voltage decreases for 0.5 seconds or more.

  • Front speed sensor RH/LH

  • Speed sensor circuit

  • Brake actuator assembly (Skid control ECU)

Tech Tips


  • DTC C1405 is for the front speed sensor RH.

  • DTC C1406 is for the front speed sensor LH.

WIRING DIAGRAM

Refer to DTCs C1401 and C1402 Click here.

CAUTION / NOTICE / HINT

Note

When replacing the brake actuator assembly (skid control ECU), perform zero point calibration Click here.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)


    1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to the DTC Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      FR Speed Open FR speed sensor open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      FL Speed Open FL speed sensor open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      OK
      There are no momentary interruptions.

      Tech Tips

      Perform the above inspection before removing the sensor and connector.


    NG

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR) Click here

    OK

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


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Start the engine.

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

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

    5. Check that there is no difference between the speed value output from the speed sensor displayed on the intelligent tester and the speed value displayed on the speedometer when driving the vehicle.

      Tech Tips

      Factors that affect the indicated vehicle speed include tire size, tire inflation, 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 intelligent tester is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).

    NG

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR) Click here

    OK

  3. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

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

      Result
      Result Proceed to
      DTCs (C1405 and C1406) are not output A
      DTCs (C1405 and/or C1406) are output (for LHD) B
      DTCs (C1405 and/or C1406) are output (for RHD) C

      Tech Tips

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


    A

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Click here

    C

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Click here

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


    1. Turn the ignition switch off.

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

    3. Disconnect the A54 or A56 brake actuator assembly (skid control ECU) connector and the A18 and/or A19 front speed sensor connector.

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

      Standard Resistance (Check for Open)
      except LHD with CVT
      Tester Connection Condition Specified Condition
      A54-7 (FR+) - A18-2 (FR+) Always Below 1 Ω
      A54-6 (FR-) - A18-1 (FR-) Always Below 1 Ω
      A54-19 (FL+) - A19-2 (FL+) Always Below 1 Ω
      A54-18 (FL-) - A19-1 (FL-) Always Below 1 Ω
      for LHD with CVT
      Tester Connection Condition Specified Condition
      A56-7 (FR+) - A18-2 (FR+) Always Below 1 Ω
      A56-6 (FR-) - A18-1 (FR-) Always Below 1 Ω
      A56-19 (FL+) - A19-2 (FL+) Always Below 1 Ω
      A56-18 (FL-) - A19-1 (FL-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      except LHD with CVT
      Tester Connection Condition Specified Condition
      A54-7 (FR+) - Body ground Always 10 kΩ or higher
      A54-6 (FR-) - Body ground Always 10 kΩ or higher
      A54-19 (FL+) - Body ground Always 10 kΩ or higher
      A54-18 (FL-) - Body ground Always 10 kΩ or higher
      for LHD with CVT
      Tester Connection Condition Specified Condition
      A54-7 (FR+) - Body ground Always 10 kΩ or higher
      A54-6 (FR-) - Body ground Always 10 kΩ or higher
      A54-19 (FL+) - Body ground Always 10 kΩ or higher
      A54-18 (FL-) - Body ground Always 10 kΩ or higher

    5. Reconnect the A54 or A56 brake actuator assembly (skid control ECU) connector and the front speed sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT SKID CONTROL ECU (SENSOR INPUT)


    1. A005IU4E01
      Text in illustration
      *a

      Front view of wire harness connector

      (to Front Speed Sensor)

      Turn the ignition switch to ON.

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

      Standard Voltage
      for RH
      Tester Connection Switch Condition Specified Condition
      A18-2 (FR+) - Body ground Ignition switch to ON 8 to 14 V
      for LH
      Tester Connection Switch Condition Specified Condition
      A19-2 (FL+) - Body ground Ignition switch to ON 8 to 14 V

      Note

      Check the speed sensor signal after replacement Click here.

      Tech Tips

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

      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    A

    REPLACE FRONT SPEED SENSOR Click here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Click here

    C

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Click here