DTC U0401: Invalid Data Received From ECM/Pcm "A"

Failure	Action
00	This DTC sets if the SECM receives invalid data in any of the PCM messages. Using a diagnostic scan tool, RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to Electronic Engine Controls - 6.2L and/or Electronic Engine Controls - 6.7L Diesel and/or Electronic Engine Controls - 7.3L article or Module Communications Network article. If the diagnostic scan tool cannot communicate with the PCM or the GWM, REFER to Module Communications Network article. If no DTCs are set in the PCM or GWM, the concern may be intermittent. 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 SECM receives invalid data in any of the PCM messages. Using a diagnostic scan tool, RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to Electronic Engine Controls - 6.2L and/or Electronic Engine Controls - 6.7L Diesel and/or Electronic Engine Controls - 7.3L article or Module Communications Network article. If the diagnostic scan tool cannot communicate with the PCM or the GWM, REFER to Module Communications Network article. If no DTCs are set in the PCM or GWM, the concern may be intermittent. 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 SECM receives invalid data in any of the PCM messages. Using a diagnostic scan tool, RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to Electronic Engine Controls - 6.2L and/or Electronic Engine Controls - 6.7L Diesel and/or Electronic Engine Controls - 7.3L article or Module Communications Network article. If the diagnostic scan tool cannot communicate with the PCM or the GWM, REFER to Module Communications Network article. If no DTCs are set in the PCM or GWM, the concern may be intermittent. 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 SECM receives invalid data in any of the PCM messages. Using a diagnostic scan tool, RETRIEVE and DIAGNOSE all PCM and GWM DTCs. REFER to Electronic Engine Controls - 6.2L and/or Electronic Engine Controls - 6.7L Diesel and/or Electronic Engine Controls - 7.3L article or Module Communications Network article. If the diagnostic scan tool cannot communicate with the PCM or the GWM, REFER to Module Communications Network k article. If no DTCs are set in the PCM or GWM, the concern may be intermittent. 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.