VOLVO
DEM-000A - Power supply. Faulty voltage
System
Differential Electronic Module (DEM)
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:
7 modelsS40 (2004–2013), S60 (2001–2009), S80 (1999–2006), V50 (2004–2013), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (14)
- Volvo S40 (2004–2013)2005–2010Transmission AW50/51 AWD, M66 AWD only
- Volvo S60 (2001–2009)2005All transmissions except: AW55-50/51SN
- Volvo S60 (2001–2009)2006–2008All transmissions except: AW55-50/51SN, TF-80SC
- Volvo S60 (2001–2009)2009Transmission AW50/51 AWD, M58 only
- Volvo S80 (1999–2006)2005–2006Transmission AW50/51 AWD only
- Volvo V50 (2004–2013)2005–2010Transmission AW50/51 AWD, M66 AWD only
- Volvo V70 (2000–2008)2005All transmissions except: AW55-50/51SN
- Volvo V70 (2000–2008)2006–2007All transmissions except: AW55-50/51SN, TF-80SC
- Volvo V70 XC / XC70 (2001–2007)2005–2007
- Volvo XC90 (2003–)2005All transmissions except: AW55-50/51SN, TF-80SC AWD
- Volvo XC90 (2003–)2006All transmissions except: AW55-50/51SN
- Volvo XC90 (2003–)2007All transmissions except: AW55-50/51SN, TF-80SC
- Volvo XC90 (2003–)2008All transmissions except: TF-80SC
- Volvo XC90 (2003–)2009Transmission AW50/51 AWD only
What does this fault code mean?
The four-wheel drive control module (DEM) keeps testing whether its supply voltage is reasonable by comparing the signal with predefined limits. The code is stored when the signal falls outside them, which can be caused by a wire lying against ground or by a broken supply. The four-wheel drive is disengaged for as long as the fault remains.
Possible causes
- Short to ground, giving too high a signal
- Break in the supply voltage, giving too low a signal
What you can do
- 1Read and erase the code, then road test to see whether it returns
- 2Check that the fuses are intact
- 3Check the connector between the control module and the connected unit for contact resistance and oxidation
- 4Check the wire between the control module and the connected unit for damage, and look for signs that it touches the body or has been chafed
- 5If you have a diagnostic tool, read the voltage to the control module with the ignition on and compare it with the battery voltage; they should be roughly the same
- 6If the code returns, have a workshop with diagnostic equipment check the supply and replace parts as needed
Symptoms you may notice1
- The four-wheel drive does not work
What the fault can affect1
- The four-wheel drive is disengaged
General guidance for car owners. Diagnosis on the car can point to a different cause.