VOLVO
CEM-B109F19 - Average Quiescent Current. General Electrical Failures. Circuit current above threshold
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsS60 (2011–), S80 (2007–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
Information about the vehicle's power supply is stored in the central electronic module (CEM) and in the battery monitoring sensor (BMS). The fault shows that the average standby current is higher than normal, which can be caused by a control module that does not sleep, an internal short in a module, or leakage current. The fault is checked when the car is in normal mode.
Possible causes
- One control module does not go to sleep mode
- One control module has an internal short circuit
- Leakage current in wiring or connectors somewhere in the car
What you can do
- 1Clear the code and check whether it returns after the car has been locked overnight
- 2Check that the cabin and luggage compartment lights are off when the car is parked
- 3Check that the battery terminal clamps are tight and clean
- 4Remove extra equipment fitted afterwards, such as an alarm or charger, and see whether the fault clears
- 5If the fault returns, have a workshop measure the standby current and find which control module or circuit draws too much
Symptoms you may notice4
- The battery is dead or has low voltage
- Warning symbol and text message about a low battery
- The engine does not start or does not turn over
- The central locking does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.