EASY AND SMOOTH START SYSTEM, Diagnostic DTC:C1249/42

DTC Code DTC Name
C1249/42 Open Circuit in Stop Light Switch Circuit

DESCRIPTION

The electric vehicle control ECU assembly receives the stop light switch signal through the STP terminal input and from the skid control ECU (brake actuator assembly) via CAN communication, and so the brake operation status is input.

DTC No. Detection Condition Trouble Area
C1249/42

When accelerating from 0.5 to 50 km/h, the stop light switch is observed to stay on for 5 times consecutively (stuck ON).

When decelerating from 50 to 0.5 km/h, the stop light switch is observed to stay off for 5 times consecutively (stuck OFF).

  • Stop light switch assembly

  • Harness or connector

  • Electric vehicle control ECU assembly

WIRING DIAGRAM

A01CIVBE01

INSPECTION PROCEDURE

Note


  • After replacing the electric vehicle control ECU assembly, perform clutch pedal stroke sensor assembly release position calibration Click here.

  • DTCs stored in the electric vehicle control ECU assembly are not cleared even after the system returns to a normal condition, so clear the DTCs after performing troubleshooting Click here.

PROCEDURE


  1. CHECK ANTI-LOCK BRAKE SYSTEM


    1. Check if an anti-lock brake system DTC is output Click here

      Tech Tips

      When C1249 or C1425 are detected, the electric vehicle control ECU will detect the stop light switch signal as ON even when the brake pedal is not being depressed.

      Result
      Result Proceed to
      DTCs (C1249 and C1425) are not output A
      DTCs (C1249 and/or C1425) are output B

    B

    GO TO ANTI-LOCK BRAKE SYSTEM Click here

    A

  2. CHECK ELECTRIC VEHICLE CONTROL ECU ASSEMBLY


    1. Turn the ignition switch off.

    2. Disconnect the B9 skid control ECU (brake actuator assembly) connector.

    3. A01CHH1E01
      Text in Illustration
      *a

      Component with harness connected

      (to Electric Vehicle Control ECU Assembly)

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E43-9 (STP) - Body ground

      Stop light switch on

      (brake pedal depressed)

      		 Below 1 V
      E43-9 (STP) - Body ground

      Stop light switch off

      (brake pedal released)

      		 20 V or higher

    NG

    INSPECT STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  3. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  4. CHECK FOR DTC


    1. Check for DTCs Click here.

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

    B

    REPLACE ELECTRIC VEHICLE CONTROL ECU ASSEMBLY Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  5. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. Turn the ignition switch off.

    2. Remove the stop light switch assembly Click here.

    3. A01CH1DE03
      Text in Illustration
      *a

      Component without harness connected

      (Stop Light Switch Assembly)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      3 - 4 Switch pin free 10 kΩ or higher
      3 - 4 Switch pin pushed in Below 1 Ω

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ELECTRIC VEHICLE CONTROL ECU ASSEMBLY)