ELECTRONICALLY CONTROLLED BRAKE SYSTEM Brake Warning Light Remains ON

DESCRIPTION

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

If any of the following is detected, the brake warning light / red (malfunction) remains on:


WIRING DIAGRAM

B002BGCE02

CAUTION / NOTICE / HINT

Note


  • When replacing the skid control ECU assembly, perform initialization and calibration of the linear solenoid valve 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 a CAN communication system DTC is output (for LHD: See page , for RHD: Click here.

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

    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    C

    INSPECT CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK DTC


    1. Check if ABS, VSC and/or electronically controlled brake system DTCs are output Click here.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output B

    B

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    A

  3. CHECK IF SKID CONTROL ECU ASSEMBLY CONNECTOR IS SECURELY CONNECTED


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

      OK
      The connector is securely connected.

    NG

    CONNECT CONNECTOR TO ECU CORRECTLY

    OK

  4. CHECK AUXILIARY BATTERY


    1. Check the auxiliary battery voltage.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Auxiliary battery Power switch on (IG) 11 to 14 V
      Auxiliary battery Power switch on (READY) 11 to 15.5 V

    NG

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    OK

  5. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)


    1. B002BBME02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU Assembly)

      Disconnect the skid control ECU assembly connector.

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A14-46 (IG1) - Body ground Power switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

    OK

  6. CHECK HARNESS AND CONNECTOR (GND TERMINAL)


    1. Turn the power switch off.

      B002B4EE02

    2. Disconnect the skid control ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A14-1 (GND) - Body ground Always Below 1 Ω
      A16-1 (GND4) - Body ground Always Below 1 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU Assembly)

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

    OK

  7. INSPECT COMBINATION METER ASSEMBLY


    1. Reconnect the skid control ECU assembly connectors.

    2. Perform the Active Test of the combination meter assembly (meter CPU) using the GTS Click here.

    3. Check the combination meter assembly.

      OK
      The brake warning light / red (malfunction) turns on or off in accordance with the GTS operation.

      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 the part Click here.


    OK

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here