DTC U0401 Invalid Data Received from ECM/PCM A: Description

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

The PSCM monitors the HS-CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 6.5 volts and there are no DTCs present inhibiting PSCM operation.

DTC U0401:68 (Invalid Data Received from ECM/PCM A: Event Information) - This DTC sets if the PSCM receives "fault" or "unknown" messages from the PCM instead of valid brake pedal position, engine speed, transmission gear or vehicle speed messages.