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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota FJ Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: When replacing the master cylinder solenoid, perform zero point calibration (See CALIBRATION  ).
  1. CHECK DTC 
    1. Check if DTCs for VSC are recorded (See DTC CHECK/CLEAR  ).

      Result 

      RESULT CHART

      Result Proceed to
      DTC not output A
      DTC output B

    B: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS  (See DIAGNOSTIC TROUBLE CODE CHART  )

    A: Go to next step 

  2. CHECK VSC OFF INDICATOR LIGHT 
    1. Disconnect the skid control ECU connector.
    2. Turn the ignition switch to ON.
    3. Check that the VSC OFF indicator light.

      Result 

      RESULT CHART

      VSC OFF Indicator Light Proceed to
      Illuminates A
      Turns off B

    B:  Go to step  4

    A: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - COMBINATION METER) 
    1. Disconnect the skid control ECU connector.
      2. Fig 1: Identifying Skid Control ECU Connector And Combination Meter Connector
      G05112347Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the combination meter connector.
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A4-35 (WT) - E14-5 (TROF) Below 1 Ω
      A4-35 (WT) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

  4. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (EXI and EXI3 TERMINALS) 
    1. Disconnect the skid control ECU connector.
      2. Fig 2: Identifying Skid Control ECU Connector Terminals
      G05579883Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the voltage.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      A4-26 (EXI3)*1 - Body ground Rear differential lock switch ON Below 1.5 V
      A4-26 (EXI3)*1 - Body ground Rear differential lock switch OFF 8 to 14 V
      A4-27 (EXI)*2 - Body ground A/T: Transfer range H4 or L4
      M/T: Transfer range HL or LL      		 Below 1.5 V
      A4-27 (EXI)*2 - Body ground A/T: Transfer range H2
      M/T: Transfer range H      		 8 to 14 V
      HINT:
      • *1: with rear differential lock
      • *2: 4WD

      Result 

      RESULT CHART

      Result Proceed to
      OK A
      NG (EXI3 terminal voltage) B
      NG (EXI terminal voltage for 4WD + A/T) C
      NG (EXI terminal voltage for 4WD + M/T) D

    B: Go to step 5 

    C:  Go to step  11

    D:  Go to step  16

    A: REPLACE MASTER CYLINDER SOLENOID  (See DISASSEMBLY )

  5. INSPECT REAR DIFFERENTIAL LOCK SWITCH 
    1. Remove the rear differential lock switch.
      2. Fig 3: Identifying Rear Differential Lock Switch
      G05112345Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the rear differential lock switch connector.
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      3-4 Released 10 kΩ or higher
      3-4 Pushed in Below 1 Ω

    NG: REPLACE DIFFERENTIAL LOCK SWITCH 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (DIFFERENTIAL LOCK SWITCH - BATTERY) 
    1. Disconnect the differential lock switch connector.
      2. Fig 4: Identifying Differential Lock Switch Connector Terminals
      G05579885Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the voltage.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      E2-3 - Body ground 11 to 14 V

    NG: CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (DIFFERENTIAL LOCK SWITCH - FOUR WHEEL DRIVE CONTROL ECU) 
    1. Disconnect the four wheel drive control ECU connector.
      2. Fig 5: Identifying Four Wheel Drive Control ECU Connector And Rear Differential Lock Switch Connector
      G05579886Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the rear differential lock switch connector.
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      L7-4 (R) - E2-4 Below 1 Ω
      L7-4 (R) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. INSPECT REAR DIFFERENTIAL LOCK INDICATOR SWITCH 
    1. Disconnect the rear differential lock indicator switch connector.
      2. Fig 6: Identifying Rear Differential Lock Indicator Switch
      G05112291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the rear differential lock indicator switch.
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      D2-1 - D2-2 Pushed Below 1 Ω
      D2-1 - D2-2 Free 10 kΩ or higher

    NG: REPLACE REAR DIFFERENTIAL LOCK INDICATOR SWITCH 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - RR DIFF LOCK IND SW 4WD ECU - METER) 
    1. Disconnect the skid control ECU connector.
      2. Fig 7: Identifying Skid Control ECU, Four Wheel Drive Control ECU And Rear Differential Lock Indicator Switch
      G05579888Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the four wheel drive control ECU connector.
    3. Disconnect the rear differential lock indicator switch connector.
    4. Disconnect the combination meter connector.
    5. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A4-26 (EXI3) - L7-1 (RLP) Below 1 Ω
      A4-26 (EXI3) - D2-2 Below 1 Ω
      A4-26 (EXI3) - E14-1 (RRSW) Below 1 Ω
      A4-26 (EXI3) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  10. INSPECT COMBINATION METER ASSEMBLY 
    1. Disconnect the four wheel drive control ECU connector.
    2. Connect the skid control ECU connector.
    3. Connect the rear differential lock indicator switch connector.
    4. Connect the combination meter connector.
    5. Turn the ignition switch to ON.
    6. Check that the rear differential lock warning light.

      Result 

      RESULT CHART

      Rear Differential Lock Warning Light Proceed to
      Illuminates A
      Turns off B

    B: REPLACE FOUR WHEEL DRIVE CONTROL ECU 

    A: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

  11. INSPECT TRANSFER INDICATOR SWITCH (for 4WD POSITION) 
    1. Disconnect the transfer indicator switch (4WD position) connector.
      2. Fig 8: Identifying Transfer Indicator Switch (For 4WD Position)
      G05112316Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the transfer indicator switch (4WD position).
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Switch Position Specified Condition
      1-2 Pushed Below 1 Ω
      1-2 Released 10 kΩ or higher

    NG: REPLACE TRANSFER INDICATOR SWITCH (for 4WD POSITION)  (See DISASSEMBLY (VF4B) or DISASSEMBLY (VF2A) )

    OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (TRANSFER INDICATOR SWITCH - FOUR WHEEL DRIVE CONTROL ECU) 
    1. Disconnect the four wheel drive control ECU connector.
      2. Fig 9: Identifying Four Wheel Drive Control ECU Connector And Transfer Indicator Switch (For 4WD Position) Connector
      G05112314Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the transfer indicator switch (for 4WD position) connector.
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      B4-6 (4WD) - B39-2 Below 1Ω
      B4-6 (4WD) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - 4WD ECU - A.D.D ACTUATOR - METER) 
    1. Disconnect the skid control ECU connector.
      2. Fig 10: Identifying Skid Control ECU Connector, Four Wheel Drive Control ECU Connector And A.D.D Actuator Connector
      G05579891Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the four wheel drive control ECU connector.
    3. Disconnect the A.D.D actuator connector.
    4. Disconnect the combination meter connector.
    5. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A4-27 (EXI) - B4-8 (ADD) Below 1 Ω
      A4-27 (EXI) - D1-3 (ADD) Below 1 Ω
      A4-27 (EXI) - E14-2 (SW) Below 1 Ω
      A4-27 (EXI) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  14. INSPECT A.D.D ACTUATOR 
    1. Disconnect the A.D.D actuator connector.
    2. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 (ADD) - Body ground 10 kΩ or higher
      Fig 11: Identifying A.D.D Actuator Connector
      G05579892Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE A.D.D ACTUATOR  (See REPLACEMENT )

    OK: Go to next step 

  15. INSPECT COMBINATION METER ASSEMBLY 
    1. Disconnect the four wheel drive control ECU connector.
    2. Connect the skid control ECU connector.
    3. Connect the A.D.D actuator connector.
    4. Connect the combination meter connector.
    5. Turn the ignition switch to ON.
    6. Check that the 4WD indicator light.

      Result 

      RESULT CHART

      4WD indicator light Proceed to
      Illuminates A
      Turns off B

    B: REPLACE FOUR WHEEL DRIVE CONTROL ECU 

    A: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

  16. INSPECT TRANSFER INDICATOR SWITCH (for CENTER DIFFERENTIAL LOCK POSITION) 
    1. Disconnect the transfer indicator switch (center differential lock position) connector.
      2. Fig 12: Identifying Transfer Indicator Switch (For Center Differential Lock Position)
      G05112316Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the transfer indicator switch (center differential lock position).
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Switch Position Specified Condition
      1-2 Pushed Below 1 Ω
      1-2 Released 10 kΩ or higher

    NG: REPLACE TRANSFER INDICATOR SWITCH (for CENTER DIFFERENTIAL LOCK POSITION)  (See DISASSEMBLY (VF4B) or DISASSEMBLY (VF2A) )

    OK: Go to next step 

  17. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - TRANSFER INDICATOR SWITCH) 
    1. Disconnect the skid control ECU connector.
      2. Fig 13: Identifying Skid Control ECU Connector, Transfer Indicator Switch Connector And Combination Meter Connector
      G05579894Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the transfer indicator switch (center differential lock position) connector.
    3. Disconnect the combination meter connector.
    4. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A4-27 (EXI) - B43-2 Below 1 Ω
      A4-27 (EXI) - E14-2 (SW) Below 1 Ω
      A4-27 (EXI) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

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