DESCRIPTION:This fault code sets when the Motor Control Module (MCM) stops receiving messages from the Aftertreatment Control Module (ACM).

MONITORED PARAMETER:ACM controller area network (CAN) communication.

TYPICAL ENABLING CONDITIONS:Always enabled

MONITOR SEQUENCE:None

EXECUTION FREQUENCY:Always enabled

TYPICAL DURATION:Two seconds

DASH LAMPS:1. MIL is solid.2. CEL and AWL Flash.

ENGINE REACTION:30 seconds shutdown.

VERIFICATION:1. Turn the ignition off.2. Disconnector the USB link from the 9 – pin connector.3. Wait five minutes.4. Reconnect the USB link and diagnostic service tool.5. Turn the ignition on and recheck for the fault code.

NOTE: If there are any battery Volta codes, fix those first. If the ECM has been programmed recently, clear codes, test drive, and release vehicle if they don’t come back.

PROBABLE CAUSES:1. Powertrain Controller Area Network (PTCAN) harness.2. ACM (computer) failure.3. CPC (computer) failure.4. Wiring between the CPC and the ACM.5. ACM/CPC not getting voltage.