VOLVO
CEM-9A02 - Interior lighting. 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?
The CEM controls the interior lighting through an output and has registered too low a signal from it. The cause may be a short to ground, a break in the signal wire or a blown fuse, and then the interior lighting does not work.
Possible causes
- Signal wire to the passenger compartment lighting shorted to ground
- Break in the signal wire to the interior lighting
- Blown fuse
What you can do
- 1Check that the fuse for the interior lighting is intact and replace it if it has blown
- 2Check that the interior lighting switch is in the auto position
- 3With the ignition on, switch the interior lighting on and off: if it does not respond the fault is permanent, and if it works the fault has occurred before
- 4With the ignition off, use a multimeter to check that the control wire has no break and no contact with ground (the body)
- 5If the fault returns, have a workshop repair the wire
Symptoms you may notice1
- The interior lighting does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.