SFI SYSTEM, Diagnostic DTC:U1103

DTC Code DTC Name
U1103 Lost Communication with Stop and Start Control Module

DESCRIPTION

The engine stop and start computer and ECM perform 2-way communication with each other via the Controller Area Network (CAN). If the engine stop and start computer cannot communicate with the ECM, the engine stop and start computer will conclude that there is a malfunction in the CAN system, illuminate the MIL and store a DTC.

DTC No. DTC Detection Condition Trouble Area
U1103

No communication between ECM and engine stop and start computer

(1 trip detection logic)

  • ECM to engine stop and start computer circuit

  • ECM

  • CAN communication system

CAUTION / NOTICE / HINT

Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC U1103)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / DTC.

    5. Read DTCs.

      Result
      Result Proceed to
      DTC U1103 is output A
      DTC U1103 and other DTCs are output B

      Tech Tips

      If any DTCs other than U1103 are output, troubleshoot those DTCs first.


    A

    GO TO CAN COMMUNICATION SYSTEM Click here

    B

    GO TO DTC CHART Click here