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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (see INITIALIZATION  ).
  1. INSPECT FUSE (STOP) 
    1. Remove the STOP fuse from the main body ECU.
    2. Measure the resistance of the fuse.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      STOP fuse Always Below 1 Ω

    NG: REPLACE FUSE 

    OK: Go to Next Step 

  2. READ VALUE OF TECHSTREAM (STOP LIGHT SWITCH) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Select the Data List mode on the Techstream.

      ABS/VSC/TRAC 

      ABS/VSC/TRAC REFERENCE CHART

      Tester Display (for IT2) Measurement Item/Range Normal Condition
      Stop Lamp SW Stop light switch / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
    4. Check that the stop light observed on the Techstream changes when the brake pedal is depressed.

      OK: When the brake pedal is depressed, the Techstream displays "ON". 

    OK: GO TO LIGHTING SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    NG: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - BATTERY) 
    1. Disconnect the A35 switch connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      A35-2 - Body ground Always 11 to 14 V
      Fig 1: Identifying A35 Switch Connector Terminals
      G04949633Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

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

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      1 - 2 Switch pin free Below 1 Ω
      1 - 2 Switch pin pushed in 10 kΩ or higher
      Fig 2: Inspecting Stop Light Switch
      G04949634Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT SWITCH 

    OK: Go to Next Step 

  5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH) 
    1. Disconnect the A21 ECU connector.
    2. Disconnect the A35 switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A21-25 (STP) - A35-1 Always Below 1 Ω
      A21-25 (STP) - Body ground Always 2 kΩ or lower
      Fig 3: Identifying A21 ECU And A35 Switch Connector Terminals
      G04949635Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND) 
    1. Disconnect the A19 and A21 ECU connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A19-1 (GND) - Body ground Always Below 1 Ω
      A21-1 (GND4) - Body ground Always Below 1 Ω
      Fig 4: Identifying A19 And A21 ECU Connector Terminals
      G04949626Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  7. RECONFIRM DTC 
    1. Clear the DTC (see DTC CHECK / CLEAR  ).
    2. Start the engine.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check if the same DTC is recorded (see DTC CHECK / CLEAR  ).

      HINT:

      Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

      Result 

      RESULT CHART

      Result Proceed To
      DTC (C1249/49) is not output A
      DTC (C1249/49) is output B

      HINT:

      If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE", refer back to the table and proceed to the next step (see PROBLEM SYMPTOMS TABLE  ).

    B: REPLACE SKID CONTROL ECU  (See REMOVAL  )

    A: END