VOLVO
CEM-B109A19 - Quiescent Current in Normal Mode. 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 vehicle's standby current draw is higher than normal, which may be due to a control module that does not sleep, an internal short in a module, or leakage current in the wiring. The code does not indicate a CEM fault, so the CEM should not be replaced unless fault tracing points to it.
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 and alarmed overnight
- 2Check that all doors, hatches and the bonnet are closed and that no light is on when the car is parked
- 3Check that the battery terminal clamps are tight and clean
- 4Remove any extra equipment fitted afterwards 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 engine does not start or does not turn over
- No clicking sound when trying to start
- The battery is dead or has low voltage
- The central locking does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.