Circuit DescriptionThe ECM has internal diagnostics that continuously run and check the internal memory.

Component LocationThe ECM mounting location varies depending on engine model and can be mounted either on or off engine.

Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault CodesThis fault code is triggered when the internal ECM diagnostics detect a read or write error internal to the module.

Action Taken When the Fault Code is ActiveThe ECM illuminates the red STOP ENGINE light and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.The engine may not start.Conditions for Clearing the Fault CodeTo validate the repair, start the engine and let it idle for 1 minute.The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.The ECM will turn off the red STOP ENGINE lamp after the diagnostic runs and passes.For On-Board Diagnostics (OBD) engines, the ECM will turn off the MIL after three consecutive trips where the diagnostic runs and passes.The “Reset All Faults” command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD engines.

Shop TalkThis fault code can only be caused by an internal ECM problem. Repairs are not possible for the ECM.

Possible Cause:1) ECM failure