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Inspection Procedure

  1. READ VALUE OF INTELLIGENT TESTER OR TECHSTREAM (STOP LIGHT SWITCH) 
    1. Check the DATA LIST for proper functioning of the stop light switch.
      1. Intelligent tester

        RADAR CRUISE 

        INTELLIGENT TESTER - RADAR CRUISE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        STP LIGHT SW1-M Stop light switch signal (Main CPU)/ON or OFF OK: Brake pedal is depressed
        OFF: Brake pedal is released
        -
        STP LIGHT SW2-M Stop light switch signal (Main CPU) / ON or OFF OK: Brake pedal is depressed
        OFF: Brake pedal is released
        -
        STP LIGHT SW1-S Stop light switch signal (Sub CPU) /ON or OFF OK: Brake pedal is depressed
        OFF: Brake pedal is released
        -
      2. Techstream

        Radar Cruise 

        TECHSTREAM - RADAR CRUISE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        Stop Light SW 1 M-CPU Stop light switch signal (Main CPU) / ON or OFF OK: Brake pedal is depressed
        OFF: Brake pedal is released
        -
        Stop Light SW 2 M-CPU Stop light switch signal (Main CPU) / ON or OFF OK: Brake pedal is depressed
        OFF: Brake pedal is released
        -
        Stop Light SW 1 S-CPU Stop light switch signal (Sub CPU) / ON or OFF OK: Brake pedal is depressed
        OFF: Brake pedal is released
        -

        OK: Display changes according to brake pedal operation described in above table. 

    NG: Go to step 2 

    OK: REPLACE DRIVING SUPPORT ECU (See  REMOVAL   ) 

  2. INSPECT FUSE (STOP, ECU-IG) 
    1. Remove the STOP fuse from the main body ECU.
    2. Remove the ECU-IG fuse from the engine room No. 2 junction block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      FUSE (STOP, ECU-IG)

      Tester Connection Condition Specified Condition
      STOP fuse Always Below 1 Ω
      ECU-IG fuse Always Below 1 Ω

    NG: REPLACE FUSE 

    OK: GO TO NEXT STEP 

  3. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Remove the stop light switch (see REMOVAL ).
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STOP LIGHT SWITCH ASSEMBLY

      Tester Connection Switch Condition Specified Condition
      1 - 2 Pushed 10 kΩ or higher
      1 - 2 Not pushed Below 1 Ω
      3 - 4 Not pushed Below 1 Ω
      3 - 4 Pushed 10 kΩ or higher
      Fig 1: Inspecting Stop Light Switch Assembly
      G04951422Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY  (See REMOVAL )

    OK: GO TO NEXT STEP 

  4. CHECK HARNESS AND CONNECTOR (ECU - BATTERY) 
    1. Disconnect the A33 ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard resistance 

      ECU - BATTERY

      Tester Connection Switch Condition Specified Condition
      A33-11 (STP-) - Body ground Brake pedal is depressed Below 1 V
      A33-11 (STP-) - Body ground Brake pedal is released 11 to 14 V
      A33-34 (ST1-) - Body ground Engine switch is on (IG), brake pedal is released 11 to 14 V
      A33-34 (ST1-) - Body ground Engine switch is on (IG), brake pedal is depressed Below 1 V
      Fig 2: Identifying A33 ECU Connector Terminal
      G04951423Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE DRIVING SUPPORT ECU (See  REMOVAL   )