VOLVO
CEM-DD1A - Communication with RRX control module. Signal missing
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?
The central module cannot reach the remote receiver (RRX) despite several attempts, so the remote control does not work. The cause may be a missing supply, earth point or signal wire to the remote receiver, or one of these may be broken.
Possible causes
- No supply voltage to the remote receiver (RRX)
- Open circuit in the ground lead to the remote receiver (RRX)
- Open circuit in the signal lead to the remote receiver (RRX)
What you can do
- 1With a multimeter, check that the remote receiver gets power, and that its earth point is clean and tight
- 2Repair the leads to the remote receiver where they are broken or chafed
- 3Test locking and unlocking the car with the remote control after the repair
- 4If the leads are intact, have a workshop replace the remote receiver
Symptoms you may notice1
- The car cannot be controlled with the remote control
General guidance for car owners. Diagnosis on the car can point to a different cause.