VOLVO
CEM-3F90 - Fuel pump relay. Open-circuit or short-circuit to ground
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–)
What does this fault code mean?
The CEM checks and activates the fuel pump relay after the immobilizer has approved its check. The relay sits inside the CEM. The code is set when the voltage on the fuel pump output is too low. The engine does not start.
Possible causes
- A damaged power supply fuse
- An open circuit in the supply wire between the engine bay fuse box and the CEM
- The supply wire between the CEM and the fuel pump is shorted to ground
What you can do
- 1Check the fuse for the fuel pump power supply in the engine bay. If it has blown, replace it once
- 2Use a multimeter to check that the wire between the CEM and the fuel pump has no break or short to ground
- 3Warning: do not connect an external power source directly to the fuel pump without first disconnecting the CEM connector, since the CEM can be damaged
- 4After the work, clear the code and check that the engine starts
Symptoms you may notice1
- The engine does not start
General guidance for car owners. Diagnosis on the car can point to a different cause.