key code?

For my Ford Mondeo 6000CD RDS-EON I need to reset the keycode since I had to renew the cars battery.
The key code delivered with the car has probably been changed by the previous owner of the car.
Can anybody inform me how to handle this?
Serial number M010045.
On the card delivered with the car it says that the system is a 6006E, on the audiosystem in the car it says 6000CD RDS-EON......