ELECTRONICALLY CONTROLLED BRAKE SYSTEM VSC OFF Switch Circuit

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 TRC operation, and pressing and holding this switch turns off TRC and VSC operation. If TRC and VSC operations are turned off, the TRC OFF indicator light and the VSC OFF indicator light will come on.

WIRING DIAGRAM

A01V1TDE02
*a VSC OFF Switch
*b Combination Meter Assembly
*c Skid Control ECU (Brake Booster with Master Cylinder Assembly)
*d CAN Communication Line

CAUTION / NOTICE / HINT

Note

When replacing the skid ECU (brake actuator assembly), perform zero point calibration and store system information.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if CAN communication system DTCs are 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 BOOSTER WITH MASTER CYLINDER ASSEMBLY 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 BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY CORRECTLY

    OK

  3. READ VALUE USING GTS (TRC/VSC OFF MODE)


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON (IG).

    4. Turn the GTS on.

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

    6. According to the display on the GTS, read the Data List.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      TRC/VSC Off Mode

      TRC/VSC off mode /

      Normal, TRC OFF, Unknown or VSC OFF

      NORMAL: Normal mode

      TRC OFF: TRC off mode

      Unknown: Unspecified

      VSC OFF: VSC off mode

      		 -

    7. Check the indicator light and mode condition on the GTS changes according to VSC OFF switch operation.

      Standard:
      Switch Operation Mode Condition Display TRC OFF Indicator Light VSC OFF Indicator Light
      Not pressed Normal Does not come on Does not come on
      Pressing the VSC OFF switch TRC OFF Comes on Does not come on
      Pressing and holding the VSC OFF switch VSC OFF Comes on Comes on
      Result
      Result Proceed to
      Indicator light and mode condition display do not change. A
      Mode condition display is normal, but indicator light does not change. B
      Yaw rate and acceleration sensor DTC is output. Indicator light and mode condition display is normal. C

    B

    INSPECT METER / GAUGE SYSTEM Click here

    C

    USE SIMULATION METHOD TO CHECK

    A

  4. PERFORM ACTIVE TEST USING GTS (VSC OFF INDICATOR LIGHT AND VSC OFF INDICATOR LIGHT)


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / ABS/VSC/TRC / Active Test.

    6. According to the display on the GTS, perform the Active Test.

      ABS/VSC/TRC
      Tester Display Test Part Control Range Diagnostic Note
      TRC(TRAC) OFF Indicator Light TRC OFF indicator light Indicator light ON/OFF Observe combination meter assembly
      VSC OFF Indicator Light VSC OFF indicator light Indicator light ON/OFF Observe combination meter assembly

    7. Check the TRC OFF indicator light and VSC OFF indicator light in the combination meter assembly turn on or off in accordance with GTS operation.

      OK
      The TRC OFF indicator light and VSC OFF indicator light turn on or off in accordance with GTS operation.

    NG

    INSPECT COMBINATION METER ASSEMBLY Click here

    OK

  5. INSPECT VSC OFF SWITCH


    1. Remove the VSC OFF switch Click here.

    2. Inspect the VSC OFF switch Click here.


    NG

    REPLACE VSC OFF SWITCH Click here

    OK

  6. CHECK HARNESS AND CONNECTOR (VSC OFF SWITCH - BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY AND BODY GROUND)


    1. Disconnect the A29 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
      A29-8 (CSW) - F78-6 Always Below 1 Ω
      A29-8 (CSW) or F78-6 - Body ground Always 10 kΩ or higher
      F78-3 - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      NG (for LHD) A
      NG (for RHD) B
      OK C

    A

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  7. INSPECT COMBINATION METER ASSEMBLY


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Body Electrical / Combination Meter / Active Test.

    6. According to the display on the GTS, perform the Active Test.

      Combination Meter
      Tester Display Test Part Control Range Diagnostic Note
      VSC TRC Indicator TRC OFF indicator light OFF or ON -
      Indicat. VSC OFF VSC OFF indicator light OFF or ON -

    7. Check the TRC OFF indicator light and VSC OFF indicator light in the combination meter assembly turn on or off in accordance with GTS operation.

      OK
      The TRC OFF indicator light and VSC OFF indicator light turn on or off in accordance with 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 parts.

      Result
      Result Proceed to
      NG (for LHD) A
      NG (for RHD) B
      OK C

    A

    BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    B

    BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    C

    INSPECT METER / GAUGE SYSTEM Click here