VEHICLE STABILITY CONTROL SYSTEM ABS Warning Light Remains ON

DESCRIPTION

The skid control ECU (brake actuator assembly) is connected to the combination meter assembly via CAN communication.

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


Tech Tips

In some cases, the GTS cannot be used when the skid control ECU (brake actuator assembly) is abnormal.

WIRING DIAGRAM

A01IUQZE01

INSPECTION PROCEDURE

Note

When replacing the skid control ECU (brake actuator assembly), perform system variant learning and acceleration sensor zero point calibration Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication system DTC is output Click here.

      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK IF BRAKE ACTUATOR ASSEMBLY CONNECTOR IS SECURELY CONNECTED


    1. Check if the skid control ECU (brake actuator assembly) connector is securely connected.

      OK
      The connector is securely connected.

    NG

    CONNECT CONNECTOR TO BRAKE ACTUATOR ASSEMBLY CORRECTLY

    OK

  3. CHECK BATTERY


    1. Check the battery voltage.

      Standard voltage
      11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (for 1ZR-FAE) B
      NG (for 2ZR-FAE) C
      NG (for 1WW) D

    B

    CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY Click here

    C

    CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY Click here

    D

    CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY Click here

    A

  4. CHECK TERMINAL VOLTAGE (POWER SOURCE TERMINAL)


    1. A01IQ6IE01
      Text in Illustration
      *A for CVT
      *B except CVT
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Brake Actuator Assembly))

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

    2. Disconnect the A78 (for CVT) or A79 (except CVT) skid control ECU (brake actuator assembly) connector.

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

      Standard Voltage (for CVT)
      Tester Connection Condition Specified Condition
      A78-25 (+BS) - Body ground Always 11 to 14 V
      A78-25 (+BS) - A78-38 (GND1) Always 11 to 14 V
      A78-28 (IG1) - Body ground Ignition switch ON 11 to 14 V
      A78-28 (IG1) - A78-38 (GND1) Ignition switch ON 11 to 14 V
      Standard Voltage (except CVT)
      Tester Connection Condition Specified Condition
      A79-1 (+BS) - Body ground Always 11 to 14 V
      A79-1 (+BS) - A79-14 (GND1) Always 11 to 14 V
      A79-4 (IG1) - Body ground Ignition switch ON 11 to 14 V
      A79-4 (IG1) - A79-14 (GND1) Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (for +BS circuit) B
      NG (w/o Stop and Start System for IG1 circuit) C
      NG (w/ Stop and Start System for IG1 circuit) D

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

    D

    INSPECT STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT) Click here

    A

  5. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)


    1. A01IQ6IE02
      Text in Illustration
      *A for CVT
      *B except CVT
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Brake Actuator Assembly))

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

      Standard Resistance (for CVT)
      Tester Connection Condition Specified Condition
      A78-38 (GND1) - Body ground Always Below 1 Ω
      Standard Resistance (except CVT)
      Tester Connection Condition Specified Condition
      A79-14 (GND1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)

    OK

  6. READ VALUE USING GTS (ABS WARNING LIGHT)


    1. Reconnect the A78 (for CVT) or A79 (except CVT) skid control ECU (brake actuator assembly) connector.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Select the Data List on the GTS Click here.

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

      ON: Warning light on

      OFF: Warning light off

      		 -

    5. Check the GTS display condition of the ABS warning light.

      Result
      Result Proceed to
      Display of the Data List remains ON. A
      Display of the Data List remains OFF. B

    B

    INSPECT METER / GAUGE SYSTEM Click here

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here