ELECTRONICALLY CONTROLLED BRAKE SYSTEM TRAC OFF Indicator Light Remains ON

DESCRIPTION

The skid control ECU (brake booster with master cylinder assembly) is connected to the combination meter assembly via CAN communication.

Pressing the VSC OFF switch turns off traction control and pressing and holding this switch turns off traction and VSC controls. If TR(A)C control is turned off, the TR(A)C OFF indicator light will come on.

WIRING DIAGRAM

A01HSPEE03

INSPECTION PROCEDURE

Note

When replacing the skid control ECU (brake booster with master cylinder assembly), perform initialization and calibration of the linear solenoid valve Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if CAN communication system DTCs are output Click here.

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

    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED


    1. Check if the skid control ECU (brake booster with master cylinder assembly) connector is securely connected.

      OK
      The connector is securely connected.

    NG

    CONNECT CONNECTOR TO ECU CORRECTLY

    OK

  3. CHECK AUXILIARY BATTERY


    1. Check the auxiliary battery voltage.

      Standard Voltage
      Tester Connection 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

    CHARGE OR REPLACE AUXILIARY BATTERY

    OK

  4. READ VALUE USING TECHSTREAM (VSC OFF SWITCH)


    1. Connect the Techstream to the DLC3.

    2. Turn the power switch on (IG).

    3. Select the Data List on the Techstream Click here.

      ABS/VSC/TRAC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      TRAC/VSC Off Mode VSC OFF switch / Normal, TRC OFF, Unknown or VSC OFF

      Normal: Normal mode

      TRC OFF: TR(A)C off mode

      Unknown: Unspecified

      VSC OFF: VSC off mode

      		 -

    4. Using the Techstream, check that the switch condition on the Techstream changes according to VSC OFF switch operation.


    NG

    INSPECT VSC OFF SWITCH Click here

    OK

  5. INSPECT COMBINATION METER ASSEMBLY


    1. Turn the power switch off.

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

    3. Check the combination meter assembly.

      OK
      The TR(A)C OFF indicator light turns on or off in accordance with Techstream 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.


    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

  6. INSPECT VSC OFF SWITCH


    1. A01HVL4E01
      Text in Illustration
      *a

      Component without harness connected

      (VSC OFF Switch)

      Turn the power switch off.

    2. Disconnect the VSC OFF switch connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      6 (+) - 3 (E) Switch is pushed in Below 1 Ω
      6 (+) - 3 (E) Switch is not pushed in 10 kΩ or higher

    NG

    REPLACE VSC OFF SWITCH Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - VSC OFF SWITCH)


    1. Disconnect the skid control ECU (brake booster with master cylinder assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A28-8 (CSW) - I130-6 (+) Always Below 1 Ω
      A28-8 (CSW) - Body ground Always 10 kΩ or higher
      I130-3 (E) - Body ground Always Below 1 Ω

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here