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Inspection Procedure

NOTE: When replacing the master cylinder solenoid, perform zero point calibration (See CALIBRATION  ).
  1. INSPECT IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED 
    1. Check the skid control ECU connector's connecting condition.

      OK: The connector is securely connected. 

    NG: CONNECT CONNECTOR TO ECU CORRECTLY 

    OK: Go to Next Step 

  2. INSPECT BATTERY 
    1. Check the battery voltage.

      Standard voltage: 11 to 14 V 

    NG: INSPECT CHARGING SYSTEM 

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - COMBINATION METER) 
    1. Disconnect the skid control ECU connector and combination meter connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION TABLE

      Tester Connection Specified Condition
      S37-33 (HDCW) - C12-14 Below 1 Ω
      S37-33 (HDCW) - Body ground 10 kΩ or higher
      Fig 1: Identifying Skid Control ECU Connector Terminals S37 & Combination Meter Connector C12-14
      G05262790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (HDCW CIRCUIT) 

    OK: Go to Next Step 

  4. INSPECT COMBINATION METER ASSEMBLY 
    1. Check the combination meter system (See HOW TO PROCEED WITH TROUBLESHOOTING ).

    NG: REPLACE COMBINATION METER ASSEMBLY 

    OK: Go to Next Step 

  5. INSPECT SKID CONTROL ECU (HDCS TERMINAL) 
    Fig 2: Identifying Skid Control ECU Connector S37
    G05262791Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION TABLE

      Tester Connection Condition Specified Condition
      S37-44 (HDCS) - Body ground Downhill assist control switch is not pushed in 10 kΩ or higher

    OK: REPLACE MASTER CYLINDER SOLENOID 

    NG: Go to Next Step 

  6. INSPECT DOWNHILL ASSIST CONTROL SWITCH 
    Fig 3: Identifying Downhill Assist Control Switch
    G04965534Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the downhill assist control switch connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION TABLE

      Tester Connection Condition Specified Condition
      D5-3 - D5-4 Switch is pushed in Below 1 Ω
      D5-3 - D5-4 Switch is not pushed in 10 kΩ or higher

    NG: REPLACE DOWNHILL ASSIST CONTROL SWITCH 

    OK: Go to Next Step 

  7. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - DOWNHILL ASSIST CONTROL SWITCH) 
    Fig 4: Identifying Skid Control ECU Connector Terminals S37 & Downhill Assist Control Switch Connector D5
    G05262793Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION TABLE

      Tester Connection Specified Condition
      S37-44 (HDCS) - D5-3 Below 1 Ω
      S37-44 (HDCS) - Body ground 10 kΩ or higher
      D5-4 - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (HDCS CIRCUIT) 

    OK: END 

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