VOLVO
CEM-B104711 - Axle level Supply. General Electrical Failures. Circuit short to ground
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsV40 (2013–), V40 Cross Country (2013–)
Show models by year and engine (2)
What does this fault code mean?
The central electronic module (CEM) supplies the level sensors with voltage and uses their signals to control the headlights. The fault shows that the supply voltage to the sensors is too low, which can be caused by a short to ground in the supply wire or by a damaged sensor.
Possible causes
- The supply cable to the sensors is shorted to ground
- Damaged sensor
What you can do
- 1Read off and note the code, clear it and carry out a short test drive to see whether it returns
- 2Check that the fuses for the headlight level control are intact
- 3Check that the connectors at the front and rear level sensors are fully engaged and not corroded
- 4Use a multimeter (ignition off, connector unplugged) to check that the supply lead to the sensors has no connection to ground
- 5If you have a diagnostic tool, follow the sensor values in live data and check that they change when the front and rear of the car are pressed down and released
- 6If the fault remains, have a workshop check the wiring and the sensors
Symptoms you may notice2
- Headlight side adjustment does not follow the steering wheel
- Headlight height adjustment does not work or is set wrongly
What the fault can affect2
- The headlights use a fixed beam length instead of an adjusted one
- Side adjustment stays fixed straight ahead
General guidance for car owners. Diagnosis on the car can point to a different cause.