VOLVO
CEM-8D07 - Left-hand stop lamp. 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 supplies the left-hand brake light directly from one output. It has registered a signal from that output that is too low, which points to a short to ground in the signal wire to the brake light. The brake light then does not come on when the pedal is pressed.
Possible causes
- The signal wire to the brake light is shorted to ground
What you can do
- 1Press the brake pedal with the ignition on. If the left brake light stays off the fault is likely permanent; if it works but the code was stored earlier, it is intermittent
- 2Check the brake light fuse and that the bulb sits firmly in its holder
- 3With the ignition off and the lamp connector unplugged, use a multimeter to check that the wire has no contact with ground (the body)
- 4Look for chafing and pinched spots along the wire to the left brake light
- 5If the fault remains, have a workshop check the circuit
- 6A brake light that does not work is a safety risk, because drivers behind cannot see you brake
Symptoms you may notice1
- The left-hand brake light does not come on when the pedal is pressed
General guidance for car owners. Diagnosis on the car can point to a different cause.