What does code U011C mean?

Q: What does code U011C mean?

Lost Communication With Rocker Arm Control Module B. U011C is a generic network communication code indicating that the engine control module (ECM) or another primary controller has lost contact with the rocker arm control module B over the vehicle's controller area network (CAN) bus. The computer has detected that expected periodic messages from that specific module have stopped arriving within the required time window, which points to a communication failure rather than a direct mechanical fault in the rocker arm system itself.

DTC codes / U01xx · Lost communication with a control module / U011C

U011CLost Communication With Rocker Arm Control Module B

U011C is a generic network communication code indicating that the engine control module (ECM) or another primary controller has lost contact with the rocker arm control module B over the vehicle's controller area network (CAN) bus. The computer has detected that expected periodic messages from that specific module have stopped arriving within the required time window, which points to a communication failure rather than a direct mechanical fault in the rocker arm system itself.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

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.