VOLVO
CEM-C1B1412 - Sensor Supply Voltage A. General Electrical Failures. Circuit short to battery
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
1 modelS80 (2007–)
Show models by year and engine (1)
What does this fault code mean?
The control module supplies voltage to several sensors in the car, including the fuel level sensor, the battery temperature sensor and the solar sensor. The fault is logged when the supply voltage becomes too high, which in this case is because the supply wire is in contact with battery voltage. It shows up as instrument lighting, fuel gauge and cabin climate problems.
Possible causes
- The voltage supply wire is short-circuited to battery voltage
What you can do
- 1Check that the fuses are intact, using the owner's manual
- 2Switch the ignition off and on and see whether the fault code returns. The output is re-enabled after each ignition cycle, so the fault shows itself if it remains
- 3Use a multimeter to check that the voltage supply wire is not in contact with the battery positive, and look for chafing on the harness
- 4If you cannot find the fault in the wire, have a workshop investigate it
Symptoms you may notice3
- Instrument lighting does not work
- The fuel gauge does not work
- The cabin temperature does not match the set value
General guidance for car owners. Diagnosis on the car can point to a different cause.