VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1249

DTC Code DTC Name
C1249 Open in Stop Light Switch Circuit

DESCRIPTION

The skid control ECU (brake actuator assembly) receives stop light switch signals and uses them to determine whether or not the brakes are applied.

DTCs may be stored if one of the following occurs:


Tech Tips

*: The skid control ECU (brake actuator assembly) may store this DTC upon judging that a stuck on malfunction has occurred when the accelerator pedal and brake pedal are depressed simultaneously. However, this does not indicate a malfunction.

DTC No. DTC Detection Condition Trouble Area
C1249

Any of the following is detected:


  • The vehicle speed is 10 km/h (6 mph) or more, the accelerator pedal is depressed, and the stop light switch is on for 60 seconds or more.

  • When the stop light switch is off, the master cylinder pressure is increased.


  • STOP fuse

  • Stop light switch assembly

  • Noise filter

  • Stop light switch circuit

  • Skid control ECU (Brake actuator assembly)

WIRING DIAGRAM

A004HZME03

CAUTION / NOTICE / HINT

Note


  • When replacing the skid control ECU (brake actuator assembly), perform VSC sensor neutral memorization Click here.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

  • The skid control ECU (brake actuator assembly) may store this DTC upon judging that a stuck on malfunction has occurred when the accelerator pedal and brake pedal are depressed simultaneously.

  • If the pedals were depressed simultaneously, clear the DTC because it is not a malfunction.

PROCEDURE


  1. READ VALUE USING GTS (STOP LIGHT SW)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Select the Data List using the GTS Click here.

      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 SW" display observed on the GTS changes according to the brake pedal operation.

      OK
      The GTS displays "ON" or "OFF" according to the brake pedal operation.

    NG
    OK
  2. READ VALUE USING GTS (MASTER CYLINDER PRESSURE SENSOR 1, STOP LIGHT SW)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Select the Data List using the GTS Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Master Cylinder Pressure Sensor 1 Master cylinder pressure sensor / Min.: -1.00 MPa, Max.: 23.99 MPa Brake pedal released: -1 to 0 MPa During brake pedal operation: Proportional to pedal pressure
      Stop Light SW Stop light switch / ON or OFF

      ON: Brake pedal depressed

      OFF: Brake pedal released

      -
    4. Check that the "Stop Light SW" and "Master Cylinder Pressure Sensor 1" displays observed on the GTS change according to the brake pedal operation.

      OK
      When the "Stop Light SW" is turned "ON", the "Master Cylinder Pressure Sensor 1" is within the standard value (0.08 to 0.27 MPa(0.81 to 2.75 kgf/cm2, 11 to 39 psi)).

    NG
    OK
  3. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off.

    4. Start the engine.

    5. Drive the vehicle and depress the brake pedal several times to test the stop light circuit.

    6. Check if the same DTC is output Click here.

      Result
      Result Proceed to
      DTC C1249 is output. A
      DTC C1249 is not output. B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Click here.


    A
    B
  4. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. A004J8ME03
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Noise Filter)

      Make sure that there is no looseness at the locking part and the connecting part of the connector.

    2. Disconnect the noise filter connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A13-3 - Body ground Always 11 to 14 V

    NG
    OK
  5. INSPECT NOISE FILTER


    1. Remove the noise filter Click here.

    2. Inspect the noise filter Click here.


    NG
    OK
  6. CHECK HARNESS AND CONNECTOR (NOISE FILTER - STOP LIGHT SWITCH ASSEMBLY)


    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    2. Disconnect the stop light switch assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      A13-2 - A22-1 Always Below 1 Ω
      A13-1 - A22-2 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A13-2 or A22-1 - Body ground Always 10 kΩ or higher
      A13-1 or A22-2 - Body ground Always 10 kΩ or higher

    NG
    OK
  7. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. Remove the stop light switch assembly Click here.

    2. Inspect the stop light switch assembly Click here.


    NG
    OK
  8. CHECK HARNESS AND CONNECTOR (STP TERMINAL)


    1. A004HOJE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Brake Actuator Assembly))

      Reconnect the stop light switch assembly connector.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    3. Disconnect the skid control ECU (brake actuator assembly) connector.

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A5-30 (STP) - Body ground Stop light switch ON (Brake pedal depressed) 11 to 14 V*
      Stop light switch OFF (Brake pedal released) Below 1.5 V

      Tech Tips

      *: The standard voltage value varies depending on the +BS terminal voltage value. The standard voltage is 85% of the +BS terminal voltage.


    OK
    NG