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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 SW FUSE) 
    1. Remove the STOP SW fuse from the main body ECU RH.
    2. Check the STOP SW fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE (STOP SW FUSE) 

    OK: GO TO Next Step 

  2. READ VALUE OF INTELLIGENT TESTER (STOP LIGHT SWITCH) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the power switch ON (IG).
    3. Select the DATA LIST mode on the intelligent tester.

      Skid control ECU: 

      DATA LIST

      Item (Display) Measurement Item / Range (Display) 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 intelligent tester changes when the brake pedal is depressed.

      OK: 

      When the brake pedal is depressed, the intelligent tester displays "ON". 

    OK:  GO TO step  8

    NG: GO TO Next Step 

  3. CHECK WIRE HARNESS (SKID CONTROL ECU - STOP LIGHT SWITCH) 
    1. Disconnect the A13 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

      Tester Connection Specified Condition
      A13-45 (STP) - A35-1 Below 1 Ω
      A13-45 (STP) - Body ground 2 kΩ or lower
      Fig 1: Identifying A13 And A35 Connectors Terminals
      G05305971Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  4. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL) 
    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

      Tester Connection Specified Condition
      A35-2 - Body ground 10 to 14 V
      Fig 2: Identifying A35 Connector Terminals
      G05305972Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

    OK: GO TO Next Step 

  5. 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

      Tester Connection Condition Specified Condition
      1 - 2 Switch pin free Below 1 Ω
      1 - 2 Switch pin pushed in 10 kΩ or higher
      Fig 3: Inspecting Stop Light Switch
      G04949634Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT SWITCH 

    OK: GO TO Next Step 

  6. CHECK WIRE HARNESS (SKID CONTROL ECU - BODY GROUND) 
    1. Disconnect the A13 and A15 ECU connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A13-1 (GND) - Body ground Below 1 Ω
      A15-1 (GND4) - Body ground Below 1 Ω
      Fig 4: Identifying A13 And A15 Connectors Terminals
      G05305962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) 

    OK: GO TO Next Step 

  7. RECONFIRM DTC 
    1. Clear the DTC (see DTC CHECK / CLEAR  ).
    2. Turn the power switch ON (READY).
    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

      Condition 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.

    B: REPLACE SKID CONTROL ECU (See  REMOVAL   ) 

    A: END 

  8. CHECK WIRE HARNESS (SKID CONTROL ECU - LUGGAGE ROOM JUNCTION BLOCK ECU) 
    1. Disconnect the A13 ECU connector.
    2. Disconnect the LG ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A13-45 (STP) - LC-32 (STPI) Below 1 Ω
      A13-45 (STP) - Body ground 2 kΩ or lower
      Fig 5: Identifying A13 And LC Connectors Terminals
      G05305975Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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