DTC U0100: Lost Communication with ECM/PCM A: Action
WARNING: This page is about a different car, the 2014 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
CARRY OUT a self-test of the PCM. If the diagnostic 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 - INTRODUCTION (EXCEPT DIESEL & HYBRID) (SECTION 0) to diagnose the PCM.