SFI SYSTEM, Diagnostic DTC:U1103

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

DESCRIPTION

The ECM and engine stop and start ECU communicate with each other via the CAN communication line. The engine stop and start ECU also communicates with other computers through the ECM. If there is a problem in this communication, the ECM sets the DTC.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
U1103 Lost Communication with Stop and Start Control Module No communication between ECM and engine stop and start ECU (1 trip detection logic).

  • ECM to engine stop and start ECU circuit

  • ECM

  • CAN communication system

 Does not come on DTC stored

WIRING DIAGRAM

A01TBCME07
*1 Engine Stop and Start ECU
*2 CAN Communication Line

CAUTION / NOTICE / HINT

Tech Tips


  • When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.

  • Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

  • If the CAN communication malfunctions, there is no data output from the ECM. In this case, some of the freeze frame data are not correct and not identical with the ECM data, but the ECM data are correct.

PROCEDURE


  1. GO TO CAN COMMUNICATION SYSTEM


    1. Go to CAN communication system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    END