U0401 BMW – Invalid Data Received From ECM/PCM

U0401 BMW Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

U0401 BMW Possible Causes

Faulty Powertrain Control Module (PCM),Powertrain Control Module (PCM) harness is open or shorted,Powertrain Control Module (PCM) circuit poor electrical connection,Faulty Transmission Control Module (TCM)

U0401 BMW Description

This diagnostic checks the validity of the two Control Area Network (CAN) messages sent by the Powertrain Control Module (PCM) containing information about the engine torque. The diagnostic checks the validity by performing a CRC and message counter check be sure the CAN messages are continuously updated by the PCM and they contain valid values.