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 Code DTC Detection Condition Trouble Area

C1405

C1406

Either condition is met:


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

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

  • Front speed sensor RH/LH

  • Skid control sensor wire

  • Speed sensor circuit

  • Skid control ECU (Master cylinder solenoid)

Tech Tips


  • DTC C1405 is for the front speed sensor RH.

  • DTC C1406 is for the front speed sensor LH.

WIRING DIAGRAM

A015CACE32

INSPECTION PROCEDURE

Note


  • After replacing the master cylinder solenoid, perform zero point calibration and store the system information Click here.

  • Check the speed sensor signal after replacement Click here.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)


    1. Using the GTS, 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 Front speed sensor RH open circuit detection/ Error or Normal Normal -
      FL Speed Open Front speed sensor LH open circuit detection/ Error or Normal Normal -
      OK
      Normal (there are no momentary interruptions).

      Tech Tips

      Perform the above inspection before removing the sensor and connector.


    NG

    INSPECT SKID CONTROL SENSOR WIRE Click here

    OK

  2. READ VALUE USING GTS (FR/FL WHEEL SPEED)


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Start the engine.

    4. Turn the GTS on.

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

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

    6. Check that there is no difference between the speed value output from the speed sensor displayed on the GTS 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, refer to the reference chart Click here.

      OK
      The speed value output from the speed sensor displayed on the GTS is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).

    NG

    INSPECT SKID CONTROL SENSOR WIRE Click here

    OK

  3. RECONFIRM DTC


    1. Clear the DTC Click here.

    2. Turn the ignition switch off.

    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 output Click here.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (for LHD) B
      DTC is output (for RHD) C

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

  4. INSPECT SKID CONTROL SENSOR WIRE


    1. Remove the skid control sensor wire Click here.

    2. A015C92E04
      Text in Illustration
      *A for RH
      *B for LH
      *1 Skid Control Sensor Wire

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      Az2-1 - z17-1 (FR-) Always Below 1 Ω
      Az2-5 - z17-2 (FR+) Always Below 1 Ω
      z17-1 (FR-) - z17-2 (FR+) Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      Az1-1 - z18-1 (FL-) Always Below 1 Ω
      Az1-5 - z18-2 (FL+) Always Below 1 Ω
      z18-1 (FL-) - z18-2 (FL+) Always 10 kΩ or higher

    NG

    REPLACE SKID CONTROL SENSOR WIRE Click here

    OK

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


    1. Install the skid control sensor wire Click here.

    2. Disconnect the A24 skid control ECU (master cylinder solenoid) connector.

    3. Disconnect the z17 and/or z18 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
      A24-3 (FR+) - z17-2 (FR+) Always Below 1 Ω
      A24-3 (FR+) - Body ground Always 10 kΩ or higher
      A24-17 (FR-) - z17-1 (FR-) Always Below 1 Ω
      A24-17 (FR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A24-18 (FL+) - z18-2 (FL+) Always Below 1 Ω
      A24-18 (FL+) - Body ground Always 10 kΩ or higher
      A24-4 (FL-) - z18-1 (FL-) Always Below 1 Ω
      A24-4 (FL-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (FR+/FL+ TERMINAL)


    1. Disconnect the speed sensor connector.

    2. Connect the A24 skid control ECU (master cylinder solenoid) connector.

    3. A0155CCE27
      Text in Illustration
      *A for RH
      *B for LH
      *a

      Front view of wire harness connector

      (to Front Speed Sensor)

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

      Standard Voltage
      for RH
      Tester Connection Switch Condition Specified Condition
      z17-2 (FR+) - Body ground Ignition switch ON 11 to 14 V
      for LH
      Tester Connection Switch Condition Specified Condition
      z18-2 (FL+) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

    A

    REPLACE FRONT SPEED SENSOR Click here