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 assembly inputs the stop light switch signal and detects the brake pedal operation status.

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

DTC Code INF Code DTC Detection Condition Trouble Area
C1249/49 520 When IG2 terminal voltage is 9.5 V or more, an open STP terminal circuit continues for 10 seconds or more.

  • STP terminal circuit

  • Skid control ECU assembly

  • No. 2 integration relay

WIRING DIAGRAM

B002BP9E02

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU assembly, perform initialization and calibration of the linear solenoid valve Click here.

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

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

    OK

  2. CHECK HARNESS AND CONNECTOR (STP TERMINAL)


    1. B002B7VE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU Assembly)

      Turn the power switch off.

    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 assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A16-25 (STP) - Body ground Stop light switch ON (Brake pedal depressed) 11 to 14 V
      A16-25 (STP) - Body ground Stop light switch OFF (Brake pedal released) Below 1.5 V
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    B

    CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY - SKID CONTROL ECU ASSEMBLY) Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  3. INSPECT NO. 2 INTEGRATION RELAY


    1. B002BLCE02
      Text in Illustration
      *a

      Component without harness connected

      (No. 2 Integration Relay)

      Remove the No. 2 integration relay Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1A-11 (STP0) - 1A-22 (GNDA) Always 3 kΩ or less
      1A-11 (STP0) - 1B-10 (GNDB) Always 3 kΩ or less

    NG

    REPLACE NO. 2 INTEGRATION RELAY Click here

    OK

  4. RECONFIRM DTC


    1. Install the No. 2 integration relay Click here.

    2. Reconnect the skid control ECU assembly connector.

    3. Turn the power switch off.

    4. Clear the DTCs Click here.

    5. Turn the power switch on (READY).

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

    7. 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

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

    B

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

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


    1. B002BW6E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to No. 2 Integration Relay)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1A-11 (STP0) - Body ground Brake pedal depressed 11 to 14 V
      Brake pedal released Below 1.5 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT NO. 2 INTEGRATION RELAY


    1. Reconnect the No. 2 integration relay connector.

    2. Disconnect the A16 skid control ECU assembly connector.

    3. 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

    OK

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    NG

    REPLACE NO. 2 INTEGRATION RELAY Click here

  7. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY - SKID CONTROL ECU ASSEMBLY)


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

    2. Disconnect the A14 skid control ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1A-3 (STOP) - A14-24 (STP2) Always Below 1 Ω
      1A-3 (STOP) - Body ground Always 10 kΩ or higher

    OK

    REPLACE NO. 2 INTEGRATION RELAY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR