VOLVO
CEM-6C55 - KVM communication. Faulty value
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
CEM checks the start blocking system through encrypted communication with several control modules, including the keyless vehicle module (KVM). The fault code is set when CEM receives an incorrect reply from the KVM, which happens because the immobilizer codes do not match. The engine then cannot be started reliably.
Possible causes
- Wrong coding in the keyless vehicle module (KVM)
- Incorrect programming of the CEM
What you can do
- 1If the starter motor does not turn, troubleshoot the starting system first, for example the battery and fuses
- 2Programming and software loading are done by a workshop, so ask a workshop to check that the KVM and the CEM have matching codes
- 3If any control module has recently been replaced, ask the workshop to load new software into it
- 4If new software in the KVM does not solve the fault, the KVM may be faulty and a workshop should replace it
Symptoms you may notice2
- Starter motor does not turn
- Engine does not start or starts unreliably
General guidance for car owners. Diagnosis on the car can point to a different cause.