ELECTRONICALLY CONTROLLED BRAKE SYSTEM TRC OFF Indicator Light Remains ON

DESCRIPTION

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

Pressing the VSC OFF switch (integration control and panel assembly) turns off traction control and pressing and holding this switch turns off traction and VSC controls. If traction control turns off, the TRC OFF message is displayed on the multi-information display.

WIRING DIAGRAM

A01FS1BE01

INSPECTION PROCEDURE

Note

When replacing the skid control ECU assembly, perform initialization and calibration of the linear solenoid valve Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication system DTC is output (for LHD: Click here, 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 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

  3. 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

    CHARGE OR REPLACE AUXILIARY BATTERY

    OK

  4. READ VALUE USING GTS (VSC OFF SWITCH)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

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

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      TRC(TRAC)/VSC OFF SW VSC OFF switch / ON or OFF

      ON: Switch on

      OFF: Switch off

      		 -
      TRC/VSC Off Mode VSC OFF switch / Normal, TRC OFF, Unknown or VSC OFF

      Normal: Normal mode

      TRC OFF: TRC off mode

      Unknown: Unspecified

      VSC OFF: VSC off mode

      		 -

    4. Using the GTS, check that the switch input and mode condition on the GTS changes according to VSC OFF switch operation.

      Result
      Result Proceed to
      OK A
      NG (Switch input and mode condition display do not change.) B
      NG (Switch input is normal, but mode condition display does not change.) C

    B

    INSPECT VSC OFF SWITCH Click here

    C

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    A

  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 GTS Click here.

    3. Check the combination meter assembly.

      OK
      The multi-information display 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.


    NG

    INSPECT METER / GAUGE SYSTEM Click here

    OK

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

  6. INSPECT VSC OFF SWITCH


    1. Remove the VSC OFF switch (integration control and panel assembly) Click here.

    2. Inspect the VSC OFF switch (integration control and panel assembly) Click here.


    NG

    REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY Click here

    OK

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


    1. Disconnect the A14 skid control ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A14-39 (CSW) - N6-15 (+) Always Below 1 Ω
      A14-39 (CSW) - Body ground Always 10 kΩ or higher
      N6-8 (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 SKID CONTROL ECU ASSEMBLY Click here