VOLVO
CEM-DE2E - Communication with the power seat module (PSM). Signal missing
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
4 modelsC30 (2007–2013), C30 Electric (2011–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (4)
What does this fault code mean?
The central electronic module (CEM) gets no response from the power seat module (PSM), so the automatic seat and mirror adjustment does not work. The fault is set when communication on the CAN network breaks down. The usual causes are power supply, earth or a loose connector at the seat module.
Possible causes
- No supply to the seat module (PSM), for example from a blown fuse or a break in the supply wire
- Open circuit in the earth wire to the seat module
- Poor contact in the connections between the module and the harness
- Open circuit in the CAN wires between the CEM and the seat module
- The seat module does not suit the car, for example a used module with different software or hardware
What you can do
- 1Test the seat with the adjustment controls. If it does not move at all, the seat module or its supply is probably at fault
- 2Check the seat fuses in the engine bay fuse box and in the CEM. If one has blown, check its circuit for a short to earth before replacing it
- 3Use a multimeter to confirm the wires from the CEM to the seat module have no break and no short to earth or supply
- 4Check that the earth point and the seat module connector are secure and free from corrosion or damage
- 5With a diagnostic tool, read the seat module ID. If it reads, the CAN communication is probably fine and the fault may be intermittent
- 6The CEM should not be replaced for this code, because the fault lies in the communication and not in the CEM itself
Symptoms you may notice1
- Automatic adjustment of the seat and mirrors does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.