VOLVO
CEM-1A05 - X-Power supply. Signal too high. Intermittent fault
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The CEM has registered that the X-supply is short-circuited to supply voltage, and the fault is intermittent. It was present at an earlier time but is no longer there. The battery may discharge at times.
Possible causes
- Short circuit to supply voltage in the X-supply
- Defective ignition switch
What you can do
- 1Check that the connectors at the CEM and the ignition switch are secure and clean
- 2Lightly move the wiring at the connectors and see whether the fault returns
- 3Check with a multimeter that the wire has no voltage when the ignition is off and the connector is disconnected
- 4If the fault returns, have a workshop replace the ignition switch
Symptoms you may notice1
- The starter motor does not turn
General guidance for car owners. Diagnosis on the car can point to a different cause.