What does code U02C1 mean?

DTC codes / U02xx · Lost communication with a control module / U02C1

U02C1Lost Communication With Hybrid/EV Electronics Coolant Pump C

U02C1 is a generic communication fault indicating that the engine control module or hybrid control module has lost the controller area network (CAN) signal from the electric coolant pump that cools the hybrid or electric vehicle electronics. The module expects regular status messages from that pump and sets this code when those messages stop arriving within the programmed timeout window.

SystemNetwork

Code typeGeneric (all makes)

SeverityHigh

Fix difficultyProfessional

AreaLost communication with a control module

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.