U0101: Lost Communication with TCM

LowNetwork/CommunicationCommunication Bus

What does U0101 mean?

U0101 is a diagnostic trouble code indicating "Lost Communication with TCM". The vehicle's main computer has lost its ability to communicate with a specific module over the data bus. This could be caused by a wiring fault, a blown fuse, or a failed control module.

Common causes

  • Failed control module
  • CAN bus wiring fault or short
  • Blown fuse to the affected module
  • Water intrusion in a connector or module
  • Battery voltage too low

What should you do?

This is a minor or informational code. Monitor for any changes in vehicle behaviour and address it during your next scheduled service visit.

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Code U0101 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.

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Related codes

U0100Lost Communication With ECM/PCM A
U0102Lost Communication with Transfer Case Control Module
U0103Lost Communication With Gear Shift Module
U0104Lost Communication With Cruise Control Module