ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1249/49

DTC Code DTC Name
C1249/49 Open in Stop Light Switch Circuit

DESCRIPTION

The skid control ECU inputs the stop light switch signal and detects braking condition.

The skid control ECU has a circuit for open detection. The skid control ECU outputs the DTC if it detects an open in the stop light signal input line when the stop light switch is off or an open in the stop light circuit (skid control ECU side).

DTC Code Information Code DTC Detection Condition Trouble Area
C1249/49 520 Stop light switch circuit is open for at least 10 seconds when IG2 terminal voltage is 9.5 V or more.

  • Stop light switch

  • Wire harness or connector

  • Skid control ECU

  • Luggage room junction block assembly (Rear junction block ECU)

WIRING DIAGRAM

A000VO4E13

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU, perform the following operations:


  • Initialization of linear solenoid valve and calibration Click here

  • Yaw rate and acceleration sensor zero point calibration Click here

PROCEDURE


  1. INSPECT STOP LIGHT SWITCH


    1. Inspect the stop light switch Click here.

      OK
      The stop light switch is normal.

    NG

    REPLACE STOP LIGHT SWITCH Click here

    OK

  2. READ VALUE USING 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.

      ABS/VSC/TRC:
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light 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".
      Result
      Result Proceed to
      NG (Intelligent tester displays "OFF".) A
      OK (Intelligent tester displays "ON".) B

    B

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH) Click here

    A

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR JUNCTION BLOCKECU)


    1. Disconnect the A21 ECU connector.

    2. Disconnect the S62 ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      A21-25 (STP) - S62-16 (STOP) Always Below 1 Ω

    OK

    GO TO LIGHTING SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH)


    1. Disconnect the A21 ECU connector.

    2. Disconnect the A95 switch connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      A21-25 (STP) - A95-2 (L) Always Below 1 Ω
      A21-25 (STP) - Body ground Always 2 kΩ or lower

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. RECONFIRM DTC


    1. Clear the DTC Click here.

    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 Click here.

      Tech Tips

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

      Result
      Result Proceed to
      DTC (C1249/49) is not output A
      DTC (C1249/49) is output for LHD B
      for RHD C

      Tech Tips

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


    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE SKID CONTROL ECU Click here

    C

    REPLACE SKID CONTROL ECU Click here