VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1203, C1270

DTC Code DTC Name
C1203 ECM Communication Circuit Malfunction
C1270 Initialization Incomplete (Test Mode DTC)

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, drivetrain and destination information sent from the ECM does not match the information stored in the skid control ECU (brake actuator assembly).

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

  3. The information on whether the rear steering control ECU is installed does not match the information stored in the skid control ECU (brake actuator assembly). (w/ DRS System)

  4. No stored information for destination.

  • An incorrect ECU is installed.

  • Skid control ECU (brake actuator assembly)
C1270 Initialization Incomplete (Test Mode DTC) Detected only during Test Mode.

  • ECM

  • Skid control ECU (brake actuator assembly)

  • CAN communication system (skid control ECU to ECM)

  • CAN communication system (skid control ECU to front steering control ECU)

  • CAN communication system (skid control ECU to rear steering control ECU)

CAUTION / NOTICE / HINT

Note


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

    Click here

  • Before replacing the ECM, refer to Service Bulletin.

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 4 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 stored.

      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 (REAR STEERING CONTROL ECU)


    1. w/ DRS System:

      Check that a correct rear steering control ECU is installed.

      w/o DRS System:

      Check that the rear steering control ECU is not installed.

      OK
      The rear steering control ECU is installed according to the vehicle specifications.

    2. Check if the rear steering control ECU had been replaced before the DTC was stored.

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

    NG

    REPLACE REAR STEERING CONTROL ECU Click here

    OK

  4. 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 stored.

      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 AND STORE SYSTEM INFORMATION Click here

    C

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

    A

  5. CLEAR AND STORE SYSTEM INFORMATION


    1. Clear the system information.

      Click here

    2. Store the system information.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. 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