Powertrain Diagnosis

CIRCUIT DESCRIPTION
The Engine Control Module (ECM) contains data which is essential to running the engine. The ECM continuously checks the integrity of this data.

CONDITIONS FOR RUNNING THE DTC
The ECM is powered up.

CONDITIONS FOR SETTING THE DTC
The ECM is unable to correctly read data from the flash memory.

ACTION TAKEN WHEN THE DTC SETS
^ The ECM illuminates the Malfunction Indicator Lamp (MIL) on the first drive trip that the diagnostic runs and fails.
^ The ECM attempts to record the operating conditions in the Freeze Frame, however since this Diagnostic Trouble Code (DTC) indicates that an internal ECM test did not pass, this information may not be useful for this specific DTC.

Diagnostic Chart:

CONDITIONS FOR CLEARING THE MIL/DTC
^ The ECM turns OFF the MIL after three consecutive drive trips that the diagnostic runs and passes.
^ A History DTC clears after forty consecutive warm-up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.
^ The scan tool clears the MIL/DTC.

DIAGNOSTIC AIDS
Ensure the engine controls power relay was not removed while the ignition was ON. This DTC and several others will set if the Switched B+ voltage is removed from the ECM while the ECM is powered up. Test for intermittent or poor connections on the switched B+ circuits at the ECM. Also test the control circuit for the engine controls power relay for in intermittent open or high resistance and inspect the terminal contact at the relay. Refer to Testing for Intermittent and Poor Connections in Diagrams.