VOLVO
CEM-6F86 - Fuel tank filler cap. Signal too low
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?
CEM controls the power supply to the fuel filler cap lock motor through a directly connected wire, and the motor is activated when the fuel filler opening switch on the light switch unit is pressed. If the wire to the motor is short-circuited to ground, the fault code is set and the fuel filler cap cannot be locked or unlocked.
Possible causes
- Supply wire to the fuel filler lock motor short-circuited to ground
What you can do
- 1With the ignition off, check the wire to the fuel filler lock motor for chafing, pinching and loose connections
- 2Use a multimeter to check that the wire to the lock motor has no contact with ground (the body)
- 3Check the connectors at the CEM and at the fuel filler lock motor for damage
- 4If no other fault is found, a workshop should replace the fuel filler lock motor
Symptoms you may notice1
- Fuel filler cap does not lock or unlock
General guidance for car owners. Diagnosis on the car can point to a different cause.