VOLVO
CEM-B10F311 - Left front position light. General Electrical Failures. Circuit short to ground
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
9 modelsS60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The CEM powers the left front position light directly from an output. The code is stored when the supply cable is short-circuited to ground, so the lamp does not light. On XC60 cars built before mid-November 2009, the position and side marker lights on the same side share one output. A broken side marker bulb can then make the CEM switch that output off, so the position light goes out too.
Possible causes
- The supply cable is short-circuited to ground
- Damaged front side marker light
- Defective front position light
What you can do
- 1Replace the bulb in the left side marker light, start the car again and check whether the code returns
- 2Check that the relevant fuses are intact. Their locations are in the owner's manual or on the fuse box cover
- 3Check that the left front position light is secure and that its connectors are clean and dry
- 4Look for chafing and pinch damage on the supply cable, especially where it may have touched the body
- 5Use a multimeter to check that the supply cable to the position light has no contact with ground (the body)
- 6If the fault returns, have a workshop with diagnostic equipment check the wiring and the control module output
Symptoms you may notice3
- Left side marker or position light does not work
- Yellow warning symbol and text message in the display
- The bulb failure warning in the instruments comes on or behaves abnormally
What the fault can affect3
- The output switches off in the driving cycle in which the fault is detected
- If the fault remains, the output switches off permanently after 100 driving cycles
- Clearing the fault codes and starting a new driving cycle resets the output
General guidance for car owners. Diagnosis on the car can point to a different cause.