VOLVO
CEM-1A67 - Communication with HCM control module Signal missing
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsS60 (2001–2009), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (4)
What does this fault code mean?
The central electronic module (CEM) has lost communication with the headlight control module (HCM) and sets this code. The fault lies in the communication, not in the CEM, so the CEM should not be replaced. The active bi-xenon function, which adjusts the sideways aim of the headlights, does not work.
Possible causes
- The HCM is not getting power
- The ground wire to the HCM is broken
- Contact resistance in the connections
- Broken CAN wiring to the HCM
- Wrong HCM for this car, for example a used module with different software or hardware
What you can do
- 1Check the HCM fuse. If it has blown, replace it once. If it blows again, use a multimeter to check the wire after it has no contact with ground.
- 2Check that the connectors to the HCM are seated and not corroded, and that the ground point is clean. Use a multimeter to check the ground wire has no break
- 3If the fault remains, use a multimeter to check the supply and ground wires to the HCM for breaks
- 4After the work, clear the code and check that the headlight side adjustment works
Symptoms you may notice1
- Headlight levelling from side to side does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.