VOLVO
CEM-9E01 - Interior lighting. Signal too low
System
Central Electronic Module (CEM)
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:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The central electronic module (CEM) supplies power to the interior lighting. The fault code is stored when the module detects an incorrect signal on the lighting output. The cause is a short circuit to ground in the power supply cable to the lighting.
Possible causes
- Short circuit to ground in the cable that supplies the interior lighting
What you can do
- 1Check that the lamp is not faulty and that its connector is secure
- 2With the ignition off, check the cable to the lighting for chafing, pinching and loose connections
- 3With the ignition off, use a multimeter to check whether the supply cable has contact with earth (the body); if it does, that is the short circuit
- 4Remedy the short circuit if it is found, reconnect the connectors and clear the fault code
- 5Switch the ignition on, open a door and check that the interior lighting comes on. If the fault remains, have a workshop with diagnostic equipment check the control module
Symptoms you may notice1
- Interior lighting does not work
What the fault can affect1
- If the fault remains over many ignition cycles, the output is switched off permanently until the fault code is cleared
General guidance for car owners. Diagnosis on the car can point to a different cause.