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

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