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DTC C1203/53 ECM Communication Circuit Malfunction: Description

The circuit is used to send TRAC and VSC control information (engine revolution signal) from the skid control ECU to the ECM (TRC+, TRC-), and engine control information from the ECM to the skid control ECU (ENG+, ENG-).

DTC TROUBLE DETECTION CHART

DTC No. DTC Detecting Condition Trouble Area
C1203/53 When any of the following is detected:
  1. All the following conditions continue for at least 5 seconds.

    * IG1 terminal voltage is 9.5 V or more.

    * Cannot send data to ECM.

  2. All the following conditions continue for at least 5 seconds.

    * IG1 terminal voltage is 9.5 V or more.

    * Engine speed is 500 rpm or more.

    * Cannot receive data from ECM.

  3. Engine, drive source and destination variations that are sent from the ECM do not match the ones of the skid control ECU.
  • TRC+ or TRC- circuit
  • ENG+ or ENG- circuit
  • ECM