ANTI-LOCK BRAKE SYSTEM ABS Warning Light Remains ON

DESCRIPTION

The skid control ECU is connected to the combination meter via CAN communication.

If any of the following is detected, the ABS warning light remains on:


Tech Tips

In some cases, the intelligent tester cannot be used when the skid control ECU is abnormal.

WIRING DIAGRAM

A01DQ07E01

INSPECTION PROCEDURE

Note


  • When replacing the brake actuator assembly, perform calibration Click here.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if CAN communication system DTCs are output (for LHD without Entry and Start System: Click here, for RHD without Entry and Start System: Click here.

      Result
      Result Proceed to
      DTC not output A
      DTC output for LHD without Entry and Start System B
      DTC output for RHD without Entry and Start System C

    B

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    C

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    A

  2. CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED


    1. Check if the skid control ECU connector is securely connected.

      OK
      The connector is securely connected.

    NG

    CONNECT CONNECTOR TO ECU CORRECTLY

    OK

  3. CHECK TERMINAL VOLTAGE (IG1)


    1. Disconnect the A6 skid control ECU connector.

    2. A01DMHLE08
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU)

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A6-34 (IG1) - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

    OK

  4. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)


    1. Disconnect the A6 skid control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A6-1 (GND1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

    OK

  5. READ VALUE USING INTELLIGENT TESTER (ABS WARNING LIGHT)


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the intelligent tester on.

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

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      ABS Warning Light ABS warning light / ON or OFF OFF -

    6. When performing the ABS Warning Light Active Test, check ABS Warning Light in the Data List Click here.

      ABS/VSC/TRC
      Tester Display Test Part Control Range Diagnostic Note
      ABS Warning Light ABS warning light Warning light ON/OFF Observe the combination meter.
      Result
      Result Proceed to
      Data List Display Data List Display when Performing Active Test ON/OFF Operation
      ON Does not change between ON and OFF A
      Changes between ON and OFF B
      OFF Does not change between ON and OFF A
      Changes between ON and OFF B

    B

    GO TO METER / GAUGE SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here