VEHICLE STABILITY CONTROL SYSTEM(for Hydraulic Brake Booster) TRC OFF Indicator Light Remains ON

DESCRIPTION

The skid control ECU is connected to the combination meter via the CAN communication system. Pressing the VSC OFF switch turns off traction control and pressing and holding this switch turns off traction control and VSC. If traction control turns off, the TRC OFF indicator light comes on.

When the temperature inside the hydraulic brake booster becomes too high, the TRC OFF indicator light turns on and traction control is stopped until the temperature decreases.


WIRING DIAGRAM

B001DGOE01

CAUTION / NOTICE / HINT

Note


  • When replacing skid control ECU (master cylinder solenoid), perform calibration Click here.

  • As there may be malfunctions in the transfer system related to when the transfer operates in L4, check the transfer system first Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION LINE


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Select CAN Bus Check from the System Selection Menu screen and follow the prompts on the screen to inspect the CAN bus (w/ Central Gateway ECU: See page , w/o Central Gateway ECU: Click here.

      OK
      CAN Bus Check indicates no malfunctions in CAN communication.
      Result
      Result Proceed to
      OK A
      NG (w/ Central Gateway ECU) B
      NG (w/o Central Gateway ECU) C

    B

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    C

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    A

  2. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID CSW CIRCUIT)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A7-9 (CSW) - Body ground VSC OFF switch not pushed in 10 kΩ or higher
      VSC OFF switch pushed in Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG (w/ Combination Switch Assembly) B
      NG (w/o Combination Switch Assembly (w/ Downhill Assist Control)) C
      NG (w/o Combination Switch Assembly (w/o Downhill Assist Control)) D

    B

    CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - COMBINATION SWITCH ASSEMBLY) Click here

    C

    CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - NO. 2 COMBINATION SWITCH ASSEMBLY) Click here

    D

    CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - VSC OFF SWITCH) Click here

    A

  3. CHECK TERMINAL VOLTAGE (EXI3)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    2. B001HJKE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Master Cylinder Solenoid))

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A7-40 (EXI3) - Body ground

      Ignition switch ON

      w/ Rear Differential Lock: Rear differential free

      		 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID EXI3 CIRCUIT) Click here

    OK

  4. 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.

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / ABS/VSC/TRC / 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 or VSC OFF

      Normal: Normal mode

      TRC OFF: TRC OFF mode

      VSC OFF: VSC OFF mode

      		 -

    6. Check that the mode display changes according to VSC OFF switch operation.

      OK
      Display changes according to switch operation.
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    A

    GO TO METER / GAUGE SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

  5. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - COMBINATION SWITCH ASSEMBLY)


    1. Disconnect the G156 VSC OFF switch (combination switch assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-9 (CSW) - G156-2 (OFF) Always Below 1 Ω
      A7-9 (CSW) - Body ground Always 10 kΩ or higher
      G156-24 (E) - Body ground Always Below 1 Ω

    OK

    INSPECT COMBINATION SWITCH ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - NO. 2 COMBINATION SWITCH ASSEMBLY)


    1. Disconnect the G156 VSC OFF switch (No. 2 combination switch assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-9 (CSW) - G156-2 (OFF) Always Below 1 Ω
      A7-9 (CSW) - Body ground Always 10 kΩ or higher
      G156-24 (E) - Body ground Always Below 1 Ω

    OK

    INSPECT NO. 2 COMBINATION SWITCH ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  7. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - VSC OFF SWITCH)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    2. Disconnect the G226 VSC OFF switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-9 (CSW) - G226-5 (OFF) Always Below 1 Ω
      A7-9 (CSW) - Body ground Always 10 kΩ or higher
      G226-2 (E) - Body ground Always Below 1 Ω

    OK

    INSPECT VSC OFF SWITCH Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. INSPECT COMBINATION SWITCH ASSEMBLY


    1. Remove the VSC OFF switch (combination switch assembly) Click here.

    2. B001EY5E01
      Text in Illustration
      *a

      Component without harness connected

      (VSC OFF Switch (Combination Switch Assembly))

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      2 (OFF) - 24 (E) Switch is not pushed 10 kΩ or higher
      Switch is pushed Below 1 Ω
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    A

    REPLACE COMBINATION SWITCH ASSEMBLY Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

  9. INSPECT NO. 2 COMBINATION SWITCH ASSEMBLY


    1. Remove the VSC OFF switch (No. 2 combination switch assembly) Click here.

    2. B001EY5E01
      Text in Illustration
      *a

      Component without harness connected

      (VSC OFF Switch (No. 2 Combination Switch Assembly))

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      2 (OFF) - 24 (E) Switch is not pushed 10 kΩ or higher
      Switch is pushed Below 1 Ω
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    A

    REPLACE NO. 2 COMBINATION SWITCH ASSEMBLY Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

  10. INSPECT VSC OFF SWITCH


    1. Remove the VSC OFF switch Click here.

    2. B001H82E01
      Text in Illustration
      *a

      Component without harness connected

      (VSC OFF Switch)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      5 (OFF) - 2 (E) Switch is not pushed 10 kΩ or higher
      Switch is pushed Below 1 Ω
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    A

    REPLACE VSC OFF SWITCH Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

  11. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID EXI3 CIRCUIT)


    1. Disconnect the A7 skid control ECU connector.

    2. Disconnect the G53 4 wheel drive control ECU connector.

    3. w/ Rear Differential Lock:

      Disconnect the E2 rear differential lock detection switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-40 (EXI3) - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (w/o Rear Differential Lock) A
      OK (w/ Rear Differential Lock) B
      NG C

    B

    INSPECT REAR DIFFERENTIAL LOCK DETECTION SWITCH (DIFFERENTIAL LOCK INDICATOR SWITCH) Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  12. CHECK TERMINAL VOLTAGE (EXI3)


    1. Disconnect the A7 skid control ECU connector.

    2. Connect the G53 4 wheel drive control ECU connector.

    3. B001HJKE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Master Cylinder Solenoid))

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A7-40 (EXI3) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    A

    REPLACE 4 WHEEL DRIVE CONTROL ECU Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

  13. INSPECT REAR DIFFERENTIAL LOCK DETECTION SWITCH (DIFFERENTIAL LOCK INDICATOR SWITCH)


    1. Remove the rear differential lock detection switch Click here.

    2. B001H6ME02
      Text in Illustration
      *a

      Component without harness connected

      (Rear Differential Lock Detection Switch)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 (GND) - 2 (+B) Pushed in Below 1 Ω
      Not pushed in 10 kΩ or higher

    NG

    REPLACE REAR DIFFERENTIAL LOCK DETECTION SWITCH (DIFFERENTIAL LOCK INDICATOR SWITCH) Click here

    OK

  14. CHECK TERMINAL VOLTAGE (EXI3)


    1. Disconnect the A7 skid control ECU connector.

    2. Connect the G53 4 wheel drive control ECU connector.

    3. B001HJKE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Master Cylinder Solenoid))

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A7-40 (EXI3) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    A

    REPLACE 4 WHEEL DRIVE CONTROL ECU Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here