Causes and Fixes U0401 Code: Invalid Data Received From ECM/PCM

How to fix a U0401 engine code: Invalid Data Received From ECM/PCM
A U0401 Code means that the vehicle ECM (Engine Control Module) and PCM (Power-train Control Module) are having problems communicating.
The ECM monitors and controls the engine, which includes air-fuel ratio, idle speed, variable valve timing, and ignition timing.
The PCM can do everything an ECM does but also coordinates with sensors to control the transmission.
The CAN (Controller Area Network) is a protocol that allows the ECM, PCM, and other modules to communicate with each other.

Possible Causes of the U0401 Code:
Issues with Power Source (Alternator Charging or Battery)
Blown Fuse (Check ECM/PCM/ECU Fuses)
Wiring Harness Open or Short (Check Connections)
ECM PCM Module Has Bad Ground
Faulty ECM PCM

By using this information user assumes all risk of use.
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