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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (See INITIALIZATION  ).
  1. CHECK STOP LIGHT SWITCH OPERATION 
    1. Check that the stop light comes on when the brake pedal is depressed and turns off when the brake pedal is released.

      OK 

      CONDITION REFERENCE

      Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

      HINT:

      Check the stop light bulb as it may have burnt out.

    NG: REPAIR STOP LIGHT CIRCUIT 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND STOP LIGHT SWITCH) 
    1. Disconnect the stop light switch connector and skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      RESISTANCE SPECIFICATION CHART

      Tester Connection Specified Condition
      S39-14 (STP) - S13-1 Below 1 Ω
      3. Fig 1: Identifying Stop Light Switch And Skid Control ECU Connector Terminals
      G05276878Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT SKID CONTROL ECU (GND TERMINAL) 
    1. Connect the skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      RESISTANCE SPECIFICATION CHART

      Tester Connection Specified Condition
      S38-1 (GND1) - Body ground Below 1 Ω
      S39-2 (GND2) - Body ground Below 1 Ω
      S39-1 (GND3) - Body ground Below 1 Ω
      S40-2 (GND4) - Body ground Below 1 Ω
      S40-1 (GND5) - Body ground Below 1 Ω
      S41-4 (GND6) - Body ground Below 1 Ω
      Fig 2: Identifying Skid Control ECU Connector Terminals
      G05276879Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Disconnect the stop light switch assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      RESISTANCE SPECIFICATION CHART

      Switch Condition Tester Connection Specified Condition
      Switch pin free 1 - 2 Below 1 Ω
      Switch pin pushed in 1 - 2 10 kΩ or higher
      3. Fig 3: Inspecting Stop Light Switch Assembly
      G05202722Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

    OK: Go to next step 

  5. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Turn the ignition switch on.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check that the same DTC is recorded (See DTC CHECK / CLEAR  ).

      HINT:

      Reinstall the sensors, connectors, etc. and store the previous vehicle conditions before rechecking for DTCs.

      Result 

      RESULT CHART

      Condition Proceed To
      DTC is not output A
      DTC is output B

    B: REPLACE SKID CONTROL ECU 

    A: END 

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