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

WARNING: This page is about a different car, the 2013 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

The PSCM will monitor the HS-CAN bus when the ignition has been on for more than 5 seconds, when the voltage to the PSCM is greater than 9 volts and when there are no DTCs present that are inhibiting PSCM operation.

DTC U0100:00 (Lost Communication with ECM/PCM A: No Sub Type Information) - This DTC sets if communications between the PSCM and the PCM fail. If the vehicle speed, engine torque or transmission gear message is missing for 1 to 5 seconds, this DTC sets.