VOLVO
CEM-B139787 - Right Camera Module. Bus Signal / Message Failures. Missing message
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsS60 (2011–), V60 (2011–), V60 Cross Country (2015–)
Show models by year and engine (3)
What does this fault code mean?
The right camera module (RCM) communicates with the CEM over the LIN bus. The fault is stored when communication with the camera module is missing for too long with the engine running. The cause is an open or short circuit in the wire between the camera module and the CEM.
Possible causes
- Open circuit or short circuit in the wire for communication with the CEM
What you can do
- 1Check that the fuses are intact
- 2With the engine running, check whether the blind spot system on the right side works, then clear the fault code and road test
- 3Check the communication wire between the right camera module and the CEM for breaks, chafing and pinch damage
- 4Check the connectors in the camera module wire: loose or oxidised connectors should be cleaned and pressed in
- 5Use a multimeter to check that the wire is continuous between the connector ends and is not short-circuited to earth or voltage
Symptoms you may notice2
- A text message appears in the display
- The blind spot monitoring system (BLIS) does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.