ANTI-LOCK BRAKE SYSTEM(for Type B), 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 C1413 and C1414.

Click here

DTC No. Detection Item DTC Detection Condition Trouble Area
C1405 Open or Short in Front Speed Sensor RH Circuit

Either of the following conditions 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

  • Speed sensor circuit

  • Skid control ECU (Brake actuator assembly)
C1406 Open or Short in Front Speed Sensor LH Circuit

Either of the following conditions 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 LH

  • Speed sensor circuit

  • Skid control ECU (Brake actuator assembly)

Tech Tips

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.

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 C1413 and C1414.

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 a DTC.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FR Speed Sensor Voltage Open Front speed sensor RH voltage open detection Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      FL Speed Sensor Voltage Open Front speed sensor LH voltage open detection Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      FR Speed Sensor Voltage Open
      FL Speed Sensor Voltage Open
      OK
      There are no momentary interruptions.

      Tech Tips

      Perform the above inspection before removing the sensor and connector.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - FRONT SPEED SENSOR) Click here

    OK

  2. READ VALUE USING GTS (FRONT SPEED SENSOR)


    1. Turn the ignition switch off.

    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.

      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 GTS is similar to the speed indicated on the speedometer.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO STEP 4 Click here

    OK

  3. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    3. Turn the ignition switch off.

    4. Start the engine.

    5. Perform a road test.

    6. Check if the same DTC is output.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTCs C1405 and C1406 are not output. A
      DTCs C1405 and/or C1406 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


    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  4. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - 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 A124 skid control ECU (brake actuator assembly) connector.

    4. Disconnect A157 or A158 front speed sensor connector.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      A124-7 (FR+) - A157-1 (FR+) Always Below 1 Ω
      A124-7 (FR+) or A157-1 (FR+) - Body ground Always 10 kΩ or higher
      A124-6 (FR-) - A157-2 (FR-) Always Below 1 Ω
      A124-6 (FR-) or A157-2 (FR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A124-19 (FL+) - A158-1 (FL+) Always Below 1 Ω
      A124-19 (FL+) or A158-1 (FL+) - Body ground Always 10 kΩ or higher
      A124-18 (FL-) - A158-2 (FL-) Always Below 1 Ω
      A124-18 (FL-) or A158-2 (FL-) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR INPUT)


    1. A01LWEXC26
      *a

      Front view of wire harness connector

      (to Front Speed Sensor)

      Reconnect the A124 skid control ECU (brake actuator assembly) connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      for RH
      Tester Connection Condition Specified Condition
      A157-1 (FR+) - Body ground Ignition switch ON 5.7 to 14 V
      for LH
      Tester Connection Condition Specified Condition
      A158-1 (FL+) - Body ground Ignition switch ON 5.7 to 14 V

      Note

      Check the speed sensor signal after replacement.

      Click here

      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

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SPEED SENSOR Click here

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here