What does code U020B mean?

Q: What does code U020B mean?

Lost Communication With Door Control Module H. U020B is a generic network communication code indicating that the module responsible for monitoring the vehicle's communication bus has lost contact with the door control module on the H circuit, which typically corresponds to a specific door such as the right rear. The computer sets this code when it expects regular status messages from that door module but does not receive them within the required time window, often due to a wiring fault, a failed module, or a power/ground issue.

DTC codes / U02xx · Lost communication with a control module / U020B

U020BLost Communication With Door Control Module H

U020B is a generic network communication code indicating that the module responsible for monitoring the vehicle's communication bus has lost contact with the door control module on the H circuit, which typically corresponds to a specific door such as the right rear. The computer sets this code when it expects regular status messages from that door module but does not receive them within the required time window, often due to a wiring fault, a failed module, or a power/ground issue.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

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.