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Inspection Procedure

  1. CHECK OPERATION OF STOP LIGHT 
    1. Check if the stop lights go on and off normally when the brake pedal is depressed and released.
    1. NG : REPAIR OR REPLACE STOP LAMP SWITCH CIRCUIT 
    2. OK : Go to next step. 
  2. READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL(STP SIGNAL AND ST1- VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / STOP LIGHT SW" and read its value displayed on the hand-held tester or OBD II scan tool.

      Standard:: 

      BRAKE PEDAL SPECIFIED CONDITION

      Brake Pedal Specified Condition
      Depressed STP Signal ON
      Released STP Signal OFF
      Fig 1: Identifying Brake Pedal Motion Released And Depressed
      G03367782Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK : CHECK FOR INTERMITTENT PROBLEMS (See  CHECK FOR INTERMITTENT PROBLEMS   ) 
    2. NG : Go to next step. 
  3. INSPECT STOP LAMP SWITCH ASSY 
    1. Measure the resistance between terminals when the switch is ON and OFF.

      Standard: 

      STOP LAMP SWITCH SPECIFIED CONDITION

      Switch Position Tester Connection Specified Condition
      ON (Free) 1 - 2 Below 1 Ω
      OFF (Pushed in) 10 kΩ or higher
    1. NG : REPLACE STOP LAMP SWITCH ASSY 
      Fig 2: Inspecting Stop Lamp Switch Assembly
      G03367783Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. OK : Go to next step. 
  4. CHECK HARNESS AND CONNECTOR(STOP LAMP SWITCH - ECM) 
    1. Disconnect the S8 stop lamp switch connector.
    2. Disconnect the E4 ECM connector.
    3. Measure the resistance between the wire harness side connectors.

      Standard (Check for open): 

      STOP LAMP SWITCH - ECM SPECIFIED CONDITION (CHECK FOR OPEN)

      Tester Connection Specified Condition
      Stop lamp switch (S8-1) - STP (E4-19) Below 1 Ω

      Standard (Check for short): 

      STOP LAMP SWITCH - ECM SPECIFIED CONDITION (CHECK FOR SHORT)

      Tester Connection Specified Condition
      Stop lamp switch (S8-1) or STP (E4-19) - Body ground 10 kΩ or higher
      Fig 3: Identifying S8 Stop Lamp Switch Connector
      G03367784Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reconnect the stop lamp switch connector.
    5. Reconnect the ECM connector.
    1. NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 
      Fig 4: Identifying E4 ECM Connector
      G03367785Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. OK : REPLACE ECM (See ) 
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