DTC U0100: Lost Communication with ECM/PCM A: Action

Action 

CARRY OUT a self-test of the PCM. If the scan tool indicates that the module is not responding, REFER to COMMUNICATIONS NETWORK to diagnose the network communication concern. If PCM DTCs are present, REFER to the ENGINE CONTROLS - POWERTRAIN DTC CHARTS AND DESCRIPTIONS (HYBRID) or ENGINE CONTROLS - POWERTRAIN DTC CHARTS AND DESCRIPTIONS - (EXCEPT HYBRID) to diagnose the PCM.