U0401 Code: Meaning, Causes, and Symptoms | OBD2 Codes
U0401 – Invalid Data Received From ECM/PCM
U0401 Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
U0401 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)
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.