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Home >> Lexus >> 2007 >> RX 400h AWD >> Repair and Diagnosis >> Brakes >> Traction Control >> Brake Control >> Electronically Controlled Brake System >> DTC C1249/49 Open in Stop Light Switch Circuit >> Inspection Procedure
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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (See INITIALIZATION ).
  1. CHECK STOP LIGHT SWITCH OPERATION 
    1. Check that the stop light comes on when the brake pedal is depressed and turns off when the brake pedal is released.

    OK 

    ILLUMINATION CONDITION CHART

    Condition Illumination Condition
    Brake pedal depressed ON
    Brake pedal released OFF

    HINT:

    Check the stop light bulb as it may have burnt out.

    NG: REPAIR STOP LIGHT CIRCUIT 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND STOP LIGHT SWITCH) 
    1. Disconnect the stop light switch connector and skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    S39-14 (STP) - S13-1 Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 1: Identifying Stop Light Switch Connector And Skid Control ECU Connector Terminal
    G05276878Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: Go to next step 

  3. INSPECT SKID CONTROL ECU (GND TERMINAL) 
    1. Connect the skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    S38-1 (GND1) - Body ground Below 1 Ω
    S39-2 (GND2) - Body ground Below 1 Ω
    S39-1 (GND3) - Body ground Below 1 Ω
    S40-2 (GND4) - Body ground Below 1 Ω
    S40-1 (GND5) - Body ground Below 1 Ω
    S41-4 (GND6) - Body ground Below 1 Ω
    Fig 2: Identifying Skid Control ECU Connector Terminal (GND Terminal)
    G05276879Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

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

    Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Switch Condition Tester Connection Specified Condition
    Switch pin free 1 - 2 Below 1 Ω
    Switch pin pushed in 1 - 2 10 kΩ or higher

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

    Fig 3: Identifying Stop Light Switch Assembly Connector Terminal
    G05202722Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: Go to next step 

  5. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR ).
    2. Turn the ignition switch on.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check that the same DTC is recorded (See DTC CHECK / CLEAR ).

      HINT:

      Reinstall the sensors, connectors, etc. and store the previous vehicle conditions before rechecking for DTCs.

    Result 

    RESULT CHART

    Condition Proceed To
    DTC is not output A
    DTC is output B

    B: REPLACE SKID CONTROL ECU 

    A: END