VOLVO
CEM-B11D487 - Low Speed Collision Mitigation By Braking Disabled. Bus Signal / Message Failures. Missing message
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
6 modelsS60 (2011–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), XC60 (2009–)
What does this fault code mean?
The Central Electronic Module (CEM) monitors the signals from the collision speed module (CVM), the brake control module (BCM) and the engine control module (ECM) for active safety. The fault is stored when the signal from any of these is missing or disturbed.
Possible causes
- Power supply to one of the modules CVM, BCM or ECM is missing
- Open circuit in the earth wire to one of the modules
- Contact resistance in the connections
- Open circuit or short circuit in the CAN wiring
- A used module with different software or hardware, which does not match this car
What you can do
- 1Check that the fuses are intact
- 2If you have a diagnostic tool, read the freeze frame data of the fault code to see which module is missing its signal
- 3Check the earth wires and connectors at the CVM, BCM and ECM, and that they are secure and not corroded
- 4Check the CAN wiring for chafing, pinch damage and breaks
- 5Drive carefully and keep a greater distance, as ABS and braking at low speed may be affected until the fault is repaired
- 6If the fault returns, have a workshop with diagnostic equipment check the module that is missing its signal
Symptoms you may notice4
- The engine does not start, or the starter does not turn over, sometimes or always
- The engine lacks power or stalls at times
- ABS does not work, or activates suddenly
- City Safety does not work or does not intervene when needed
General guidance for car owners. Diagnosis on the car can point to a different cause.