VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1249/49

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

DESCRIPTION

The skid control ECU (housed in the actuator assembly) inputs the stop light switch signal and the condition of brake operation.

The skid control ECU has an open detection circuit, which outputs this DTC when detecting an open in the stop light input line or the ground line of the stop light circuit with the stop light switch off (brake pedal not depressed).

DTC Code DTC Detection Condition Trouble Area
C1249/49 After the ignition switch is turned to ON, the STP terminal voltage of the ECU is 40% to 67% of its supplied voltage for 3 seconds.
  • STOP fuse

  • Stop light switch

  • Stop light switch circuit

  • Stop light control (BRK) relay

  • Stop light control (BRK) relay circuit

  • Brake actuator assembly (Skid control ECU)

WIRING DIAGRAM

A01EJ2ZE01
A01EJQSE02

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK STOP LIGHT OPERATION


    1. Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

      OK
      Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

    NG
    OK
  2. READ VALUE USING GTS (STOP LIGHT SWITCH)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Select the Data List on 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 switch display observed on the GTS changes according to brake pedal operation.

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

    NG
    OK
  3. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Depress the brake pedal several times to test the stop light circuit.

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1249/49) is not output A
      DTC (C1249/49) is 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 Click here.


    B
    A
  4. INSPECT STOP FUSE


    1. A01EL0XE05
      Text in Illustration
      *1 Main Body ECU (Driver Side Junction Block)
      *2 STOP Fuse

      Remove the STOP fuse from the main body ECU (driver side junction block).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      STOP (10 A) fuse Always Below 1 Ω

    NG
    OK
  5. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)


    1. A01EJ79E05
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Stop Light Switch)

      Install the STOP fuse.

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

    3. Disconnect the stop light switch connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A35-2 - Body ground Always 11 to 14 V

    NG
    OK
  6. INSPECT STOP LIGHT SWITCH


    1. A01ELK6E03

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

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

    NG
    OK
  7. INSPECT STOP LIGHT CONTROL (BRK) RELAY


    1. A01EKUCE04
      Text in Illustration
      *1 Stop Light Control (BRK) Relay

      Remove the stop light control (BRK) relay.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 4 Voltage is not applied between terminals 1 and 2 Below 1 Ω

    NG
    OK
  8. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - ENGINE ROOM RELAY BLOCK)


    1. A01EIXBE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Stop Light Switch)

      *2 Engine Room Relay Block
      *3 Stop Light Control (BRK) Relay

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A35-1 - Stop light control (BRK) relay terminal 4 Always Below 1 Ω

    NG
    OK
  9. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM RELAY BLOCK)


    1. A01ELF6E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Brake Actuator (Skid Control ECU))

      *2 Engine Room Relay Block
      *3 Stop Light Control (BRK) Relay

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

    2. Disconnect the skid control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A42-30 (STP) - Stop light control (BRK) relay terminal 3 Always Below 1 Ω

    NG
    OK
  10. RECONFIRM DTC


    1. Clear the DTCs Click here.

    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 Click here.

      Tech Tips

      Reinstall the relay, 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 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 Click here.


    B
    A
  11. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM RELAY BLOCK)


    1. A01ELF6E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Brake Actuator (Skid Control ECU))

      *2 Engine Room Relay Block
      *3 Stop Light Control (BRK) Relay

      Turn the ignition switch off.

    2. Remove the stop light control (BRK) relay.

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

    4. Disconnect the skid control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A42-30 (STP) - Stop light control (BRK) relay terminal 3 Always Below 1 Ω

    NG
    OK