ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1203/95

DTC Code DTC Name
C1203/95 ECM Communication Circuit Malfunction

DESCRIPTION

The circuit is used to send TRC and VSC information from the skid control ECU to the front steering control ECU (VGRS ECU) and rear steering control ECU (DRS ECU), variable gear ratio steering system information from the front steering control ECU (VGRS ECU) to the skid control ECU, and dynamic rear steering system information from the rear steering control ECU (DRS ECU) to the skid control ECU via the CAN communication system.

DTC Code INF Code DTC Detection Condition Trouble Area
C1203/95 -

Any of the following is detected:


  1. The information stored in the skid control ECU assembly does not match with the information about whether or not there is a front steering control ECU (VGRS ECU).

  2. The information stored in the skid control ECU assembly does not match with the information about whether or not there is a rear steering control ECU (DRS ECU).

  3. An improper skid control ECU assembly is installed.

  4. The skid control assembly is malfunctioning.

  • Front steering control ECU (VGRS ECU) with wrong part number installed or ECU malfunctioning

  • Rear steering control ECU (DRS ECU) with wrong part number installed or ECU malfunctioning

  • Skid control ECU assembly

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. PERFORM INITIALIZATION AND CALIBRATION OF LINEAR SOLENOID VALVE


    1. Perform initialization and calibration of the linear solenoid valve Click here.

      Tech Tips

      Before carrying out Perform Initialization and Calibration of Linear Solenoid Valve, C1203/95 will be output.


    NEXT

  2. RECONFIRM DTC


    1. Turn the power switch off.

    2. Clear the DTCs Click here.

    3. Turn the power switch on (IG).

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

      Result
      Result Proceed to
      DTC (C1203/95) is output A
      DTC (C1203/95) is not output B

    B

    END

    A

  3. CHECK PART NUMBER (FRONT STEERING CONTROL ECU [VGRS ECU])


    1. For vehicles with the VGRS system, check that the part number of the installed front steering control ECU (VGRS ECU) is correct. For vehicles without the VGRS system, make sure that a front steering control ECU (VGRS ECU) is not installed.

      OK
      The presence or absence of the front steering control ECU (VGRS ECU) appropriately matches the specifications of the vehicle.

    2. Check if the front steering control ECU (VGRS ECU) had been replaced before the DTC was stored.

      OK
      ECU had not been replaced.

    NG

    REPLACE FRONT STEERING CONTROL ECU Click here

    OK

  4. CHECK PART NUMBER (REAR STEERING CONTROL ECU [DRS ECU])


    1. For vehicles with the DRS system, check that the part number of the installed rear steering control ECU (DRS ECU) is correct. For vehicles without the DRS system, make sure that a rear steering control ECU (DRS ECU) is not installed.

      OK
      The presence or absence of the rear steering control ECU (DRS ECU) appropriately matches the specifications of the vehicle.

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

      OK
      ECU had not been replaced.

    NG

    REPLACE REAR STEERING CONTROL ECU Click here

    OK

  5. CHECK PART NUMBER (SKID CONTROL ECU ASSEMBLY)


    1. Check that a proper skid control ECU assembly is installed.

      OK
      Proper skid control ECU assembly is installed.

    2. Check if the skid control ECU assembly had been replaced before the DTC was stored.

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

    B

    CHECK INITIALIZATION AND CALIBRATION OF LINEAR SOLENOID VALVE Click here

    C

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    A

  6. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Turn the power switch on (IG).

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

      Result
      Result Proceed to
      DTC (C1203/95) is not output A
      DTC (C1203/95) is output B

    B

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

  7. CHECK INITIALIZATION AND CALIBRATION OF LINEAR SOLENOID VALVE


    1. After replacing the skid control ECU assembly, check that the initialization and calibration of the linear solenoid valve is being performed.

      OK
      Initialization and calibration of the linear solenoid valve is being performed.

      Tech Tips

      If a new skid control ECU assembly is installed, C1203/95 is output before initialization and calibration of the linear solenoid valve is performed.


    NG

    PERFORM INITIALIZATION AND CALIBRATION OF LINEAR SOLENOID VALVE Click here

    OK

    REPLACE SKID CONTROL ECU ASSEMBLY Click here