VOLVO
CEM-8F17 - Xenon lamp left. Faulty signal
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 central electronic module (CEM) has logged an incorrect reading from the left xenon lamp. The fault may be caused by a defective control box for the lamp or a damaged control unit for the gas discharge lamp (GDL), since the control box supplies the lamp with the correct voltage and current.
Possible causes
- Defective control box for the xenon lamp
- Damaged control unit for the gas discharge lamp (GDL)
What you can do
- 1Switch between low and high beam with the ignition on to see whether the fault is permanent or has occurred before
- 2Check that the control box receives power and that the ground point for the left headlamp is tight and clean
- 3Look for looseness, corrosion and damage in the connectors to the control box
- 4Use a multimeter to check that the supply wire to the control box has voltage with the ignition on
- 5If the fault remains after these checks, have a workshop replace the left headlamp
Symptoms you may notice4
- The low beam is constantly lit
- The high beam is constantly lit
- Road surface lighting does not work
- Headlamp aim is wrong or the height adjustment does not work
What the fault can affect1
- The shortest beam range is used
General guidance for car owners. Diagnosis on the car can point to a different cause.