DTC U0401: Invalid Data Received from ECM/PCM A

Failure	Action
00	This DTC sets if the SASM receives invalid data in the gear lever position message or the power pack status message. RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to the Diagnosis and Testing in Module Communications Network article or the applicable Electronic Engine Controls article. If there are no DTCs in the PCM or GWM, the DTC may be caused by an intermittent concern. SET the ignition to OFF. DISCONNECT and INSPECT all PCM and GWM electrical connectors and related in-line connectors for corrosion, bent pins, pushed-out pins and spread terminals. REPAIR as necessary.
81	This DTC sets if the SASM receives invalid data in the vehicle speed quality factor check message. RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to the Diagnosis and Testing in Module Communications Network article or the applicable Electronic Engine Controls article. If there are no DTCs in the PCM or GWM, the DTC may be caused by an intermittent concern. SET the ignition to OFF. DISCONNECT and INSPECT all PCM and GWM electrical connectors and related in-line connectors for corrosion, bent pins, pushed-out pins and spread terminals. REPAIR as necessary.
82	This DTC sets if the SASM receives invalid data in the vehicle speed counter check message. RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to the Diagnosis and Testing in Module Communications Network article or the applicable Electronic Engine Controls article. If there are no DTCs in the PCM or GWM, the DTC may be caused by an intermittent concern. SET the ignition to OFF. DISCONNECT and INSPECT all PCM and GWM electrical connectors and related in-line connectors for corrosion, bent pins, pushed-out pins and spread terminals. REPAIR as necessary.
83	This DTC sets if the SASM receives invalid data in the vehicle speed checksum check message. RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to the Diagnosis and Testing in Module Communications Network article or the applicable Electronic Engine Controls article. If there are no DTCs in the PCM or GWM, the DTC may be caused by an intermittent concern. SET the ignition to OFF. DISCONNECT and INSPECT all PCM and GWM electrical connectors and related in-line connectors for corrosion, bent pins, pushed-out pins and spread terminals. REPAIR as necessary.