VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1203

DTC Code DTC Name
C1203 ECM Communication Circuit Malfunction

DESCRIPTION

This circuit is used to send TRC and VSC operation information from the skid control ECU (brake actuator assembly) to the ECM, and engine control information from the ECM to the skid control ECU (brake actuator assembly) via CAN communication.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1203 ECM Communication Circuit Malfunction

Any of the following is detected:


  1. Engine, drive source and destination variations that are sent from the ECM do not match the ones of the skid control ECU (brake actuator assembly).

  2. The information on whether the front steering control ECU is installed does not match with the one stored in the skid control ECU (brake actuator assembly). (w/ VGRS system)

  3. No stored information for destination.

  • The wrong ECU was installed

  • Skid control ECU (brake actuator assembly)

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake actuator assembly), perform zero point calibration and store system information.

Click here

PROCEDURE


  1. CHECK PART NUMBER (ECM)


    1. Check that the proper ECM is installed.

      OK
      Proper ECM is installed.

    2. Check if the ECM was replaced before the DTC was stored.

      OK
      ECM was not replaced.
      Result
      Result Proceed to
      OK (w/ VGRS system) A
      OK (w/o VGRS system) B
      NG (A proper ECM is not installed and/or the ECM was replaced.) C

    B

    GO TO STEP 3 Click here

    C

    REPLACE ECM for 2GR-FSE: Click here
    REPLACE ECM for 8AR-FTS: Click here

    A

  2. CHECK PART NUMBER (FRONT STEERING CONTROL ECU)


    1. Check that a proper front steering control ECU is installed.

      OK
      Proper front steering control ECU is installed.

    2. Check if the front steering control ECU had been replaced before the DTC was recorded.

      OK
      Front steering control ECU had not been replaced.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT STEERING CONTROL ECU for LHD: Click here
    REPLACE FRONT STEERING CONTROL ECU for RHD: Click here

    OK

  3. CHECK PART NUMBER (BRAKE ACTUATOR ASSEMBLY)


    1. Check that a proper skid control ECU (brake actuator assembly) is installed.

      OK
      Proper skid control ECU (brake actuator assembly) is installed.

    2. Check if the skid control ECU (brake actuator assembly) had been replaced before the DTC was recorded.

      OK
      Skid control ECU (brake actuator assembly) had not been replaced.
      Result
      Result Proceed to
      OK A
      NG (The skid control ECU (brake actuator assembly) had been replaced.) B
      NG (A proper skid control ECU (brake actuator assembly) is not installed.) C

    B

    PERFORM ZERO POINT CALIBRATION OF YAW RATE AND ACCELERATION SENSOR Click here

    C

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here

    A

  4. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Turn the engine switch on (IG).

    4. Check if the same DTC is output.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTC C1203 is not output. A
      DTC C1203 is output. B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here