VOLVO
CEM-U002888 - Extended CAN Communication Bus. Bus Signal / Message Failures. Bus off
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsS60 (2011–), V60 (2011–), V60 Cross Country (2015–), XC60 (2009–)
Show models by year and engine (4)
What does this fault code mean?
The control module on the extended CAN network has received or sent faulty messages and has shut off its own communication, which is called bus-off. The cause is a break in one or both CAN wires in part of the network. The control module can then no longer talk to the rest of the car, and functions such as the park assist camera and cross traffic alert stop working.
Possible causes
- Broken wiring: one or both CAN wires are open in part of the extended network
What you can do
- 1Read and note the fault codes in the modules you can reach, clear them and road test the car to see if the code returns
- 2Switch the ignition off and check the CAN wires for breaks, chafing and loose connectors, especially where wires branch
- 3With the battery negative lead disconnected, use a multimeter to confirm the wires are unbroken to the next connector. Wiggle plugs
- 4If the code returns, have a workshop with diagnostic equipment check the network. Replace the CEM only if testing shows it is faulty
Symptoms you may notice3
- Park assist camera does not work
- Blind spot monitoring (BLIS) does not function
- Cross Traffic Alert (CTA) does not work
What the fault can affect1
- The control module switches off its communication (bus-off) and no longer takes part in the network
General guidance for car owners. Diagnosis on the car can point to a different cause.