CEM-B102408: Start Control Unit. General Failure Information. Bus Signal / Message Failures (2012): Fault-Tracing: Information

Central Electronic Module (CEM) has not contacted the key.

Try with another key belonging to the vehicle.

If it works with another key, you can try adding the key that is not working with the service "Add or delete keys".

If another key does not work, it is an indication that the ignition antenna unit (IAU) is defective and must be replaced.

Other information 

• see IGNITION ANTENNA UNIT (IAU)

Fig 1: Identifying Central Electronic Module (CEM)

Courtesy of VOLVO CARS CORPORATION