VOLVO
CEM-U002811 - Extended CAN Communication Bus. General Electrical Failures. Circuit short to ground
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 fault code means that one of the wires in the extended CAN network has contact with ground (the car body). The extended network is the part where the control modules for the park assist camera, blind spot system and rear cross traffic alert talk to the rest of the car. Contact with ground disturbs the signals, and the systems on that network can stop working.
Possible causes
- Chafed or pinched wiring lets one extended-network wire touch ground
What you can do
- 1Read the fault codes in all control modules, clear them and road test the car to see whether the code returns
- 2Switch the ignition off and check the extended CAN wiring for chafing, pinch damage and loose connectors
- 3With the battery negative lead disconnected, use a multimeter to confirm the wires have no contact with ground. Twist the harness during the test
- 4If the fault remains after the wiring check, have a workshop with diagnostic equipment measure the voltage drop in the wires
Symptoms you may notice3
- Park assist camera does not work
- Blind spot monitoring (BLIS) does not function
- Cross Traffic Alert (CTA) does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.