VOLVO
CEM-1A25 - Relay Ext X2-Power supply. Signal too low. Intermittent fault
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (11)
- Volvo S60 (2001–2009)2001–2002
- Volvo S60 (2001–2009)2003All transmissions except: M58
- Volvo S60 (2001–2009)2004Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo S80 (1999–2006)2000–2004
- Volvo V70 (2000–2008)2000–2002
- Volvo V70 (2000–2008)2003All transmissions except: M58
- Volvo V70 (2000–2008)2004Transmission AW50/51 AWD, AW55-50/51SN only
- Volvo V70 XC / XC70 (2001–2007)2001–2002
- Volvo V70 XC / XC70 (2001–2007)2003–2004Transmission AW50/51 AWD only
- Volvo XC90 (2003–)2003
- Volvo XC90 (2003–)2004All transmissions except: M66 AWD
What does this fault code mean?
This fault concerns the automatic transmission. The CEM has registered an open circuit or a short to ground in the signal wire to the extended X-supply relay, or that the relay is not seated correctly. The fault is intermittent, and gear changes may then fail to happen.
Possible causes
- Incorrectly installed relay
- Contact resistance in the relay terminal
What you can do
- 1Check that the relay sits correctly in its place and is fully pushed in
- 2Check that the relay connection is secure and clean
- 3Clear the code and road test the car to see whether it returns
- 4If the fault returns, have a workshop replace the relay
Symptoms you may notice1
- No gear changes
General guidance for car owners. Diagnosis on the car can point to a different cause.