Hi bpaz_ph,

Your radio is a Becker BE-754. That radio does not have a direct entry code system in it but rather a dealer only reset proceedure. Chances are the internal battery inside the radio is dead and will come up with the dashed lines every time you disconnect the battery of your car until you have the radios battery changed. If you need futher help feel free to contact me via my WEB site at www.mercedesradiorepair.net

Cleeve Morrison
La Jolla Audio Repair