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 message will be displayed on the multi-information display and the VSC OFF indicator light will come on.

WIRING DIAGRAM

A001QV6E08

CAUTION / NOTICE / HINT

Note

After replacing the skid control ECU (brake booster with master cylinder assembly), perform linear solenoid valve offset learning, ABS holding solenoid valve learning, yaw rate and acceleration sensor zero point calibration and system information memorization after performing "Reset Memory".

Click here

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
    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.
      Result
      Proceed to
      OK
      NG

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


    1. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      TRC/VSC Off Mode TRC/VSC off mode Normal, TRC OFF, VSC Expert Mode or VSC OFF

      Normal: Normal mode

      TRC OFF: TRC off mode

      VSC Expert Mode: VSC expert mode

      VSC OFF: VSC off mode

      -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      TRC/VSC Off Mode
    2. Check the indicator light and mode condition on the GTS changes according to VSC OFF switch operation.

      Standard
      Switch Operation Mode Condition Display Multi-information Display (TRC OFF message) VSC OFF Indicator Light
      Not pressed Normal Not displayed Does not come on
      Pressing the VSC OFF switch (electric parking brake switch assembly) TRC OFF Displayed Does not come on
      Pressing and holding the VSC OFF switch (electric parking brake switch assembly) VSC OFF Displayed 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
      Indicator light and mode condition display are normal. C

    B
    C
    A
  4. PERFORM ACTIVE TEST USING GTS (TRC (TRAC) OFF INDICATOR LIGHT AND VSC OFF INDICATOR LIGHT)


    1. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      TRC(TRAC) OFF Indicator Light Multi-information display (TRC OFF message) Display ON/OFF Observe combination meter assembly
      VSC OFF Indicator Light VSC OFF indicator light Indicator light ON/OFF Observe combination meter assembly

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      TRC(TRAC) OFF Indicator Light

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      VSC OFF Indicator Light
    2. Check the multi-information display (TRC OFF message) and VSC OFF indicator light on the combination meter assembly turn on or off in accordance with GTS operation.

      OK
      The multi-information display (TRC OFF message) and VSC OFF indicator light turn on or off in accordance with GTS operation.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  5. INSPECT ELECTRIC PARKING BRAKE SWITCH ASSEMBLY


    1. Remove the electric parking brake switch assembly.

      Click here

    2. Inspect the electric parking brake switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG
    OK
  6. CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - ELECTRIC PARKING BRAKE SWITCH ASSEMBLY)


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

      OK
      The connector is securely connected.
    2. Disconnect the A39 skid control ECU (brake booster with master cylinder assembly) connector.

    3. Check both the connector case and the terminals for deformation and corrosion.

      OK
      No deformation or corrosion.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      A39-18 (CSW) - F67-13 (+) Always Below 1 Ω
      A39-18 (CSW) or F67-13 (+) - Body ground Always 10 kΩ or higher
      F67-8 (E) - Body ground Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      A39-18 (CSW) - F67-11 (+) Always Below 1 Ω
      A39-18 (CSW) or F67-11 (+) - Body ground Always 10 kΩ or higher
      F67-8 (E) - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A
    B
    C
  7. INSPECT COMBINATION METER ASSEMBLY


    1. Perform the Active Test of the combination meter assembly using the GTS.

      Click here


      Body Electrical > Combination Meter > Active Test
      Tester Display
      Meter Display 1

      Body Electrical > Combination Meter > Active Test
      Tester Display
      Indicat. VSC OFF
    2. Check the combination meter assembly.

      OK
      The multi-information display and VSC OFF indicator light turn on or off in accordance with GTS operation.
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A
    B
    C