What does code U02B9 mean?

Q: What does code U02B9 mean?

Lost Communication With Rear Radar Module D. U02B9 is a generic communication fault indicating that the vehicle's main control modules have lost contact with the rear radar module designated as 'D' on the controller area network (CAN) bus. The computer has detected that expected periodic messages from that specific radar module are no longer arriving within the required time window, which can disable rear cross-traffic alert and blind spot monitoring functions.

DTC codes / U02xx · Lost communication with a control module / U02B9

U02B9Lost Communication With Rear Radar Module D

U02B9 is a generic communication fault indicating that the vehicle's main control modules have lost contact with the rear radar module designated as 'D' on the controller area network (CAN) bus. The computer has detected that expected periodic messages from that specific radar module are no longer arriving within the required time window, which can disable rear cross-traffic alert and blind spot monitoring functions.

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.