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Inspection Procedure

  1. READ VALUE OF INTELLIGENT TESTER 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch to the ON position, and turn the intelligent tester main switch on.
    3. Select the item "STP LIGHT SW2 M", "STP LIGHT SW2 S" and "STP LIGHT SW1 S" in the DATA LIST, and read its value displayed on the intelligent tester.
    4. Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

      CCS (ECM): 

      CCS (ECM) DATA LIST

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

      OK: 

      When the brake pedal is operated, the normal conditions listed above are shown on the display. 

      Result 

      RESULT CHART

      Result Proceed to
      NG A
      OK (When troubleshooting according to the PROBLEM SYMPTOM TABLE) B
      OK (When troubleshooting according to the DTC chart) C

    A: GO TO NEXT STEP 

    B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

    C: REPLACE ECM 

  2. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Disconnect the stop light switch assembly connector.
    2. Measure the resistance according to the values in the table below.

      Resistance 

      RESISTANCE SPECIFICATION

      Switch condition Tester connection Specified value
      Switch pin free 1 - 2 Below 1 Ω
      Switch pin free 3 - 4 10 kΩ or higher
      Switch pin pushed in 1 - 2 10 kΩ or higher
      Switch pin pushed in 3 - 4 Below 1 Ω
      Fig 1: Inspecting Stop Light Switch Assembly
      G05195918Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

  3. CHECK HARNESS AND CONNECTOR 
    1. Measure the voltage according to the value(s) in the table below.

      Voltage 

      VOLTAGE SPECIFICATION

      Tester connection Condition Specified condition
      S7-2 - Body ground Always 10 to 14 V
      S7-3 - Body ground Ignition SW ON 10 to 14 V
      Fig 2: Identifying Stop Light Switch Connector Terminals
      G05236817Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

  4. INSPECT ECM 
    1. Reconnect the stop light switch connector.
    2. Disconnect the connector from the ECM.
    3. Turn the ignition switch to the ON position.
    4. Measure the voltage according to the value(s) in the table below.

      Voltage 

      VOLTAGE SPECIFICATION

      Tester connection Condition Specified condition
      E5-19 (STP) - Body ground Brake pedal depressed 10 to 14 V
      E5-19 (STP) - Body ground Brake pedal released Below 1 V
      E5-12 (ST1-) - Body ground Brake pedal depressed Below 1 V
      E5-12 (ST1-) - Body ground Brake pedal released 10 to 14 V
      Fig 3: Identifying ECM Connector E5 Terminals
      G05195920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPLACE ECM 

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR