1991 420SEL Radio problems
 

Irecently purchaseda 1991 Mercedes 420SEL and it came with afactory Mercedes Benz radio whenI turn the radio on all it does is flash "wait" no matter what I do thats all it does. I think the radio in it isnot original because when Iremoved it to try a different oneout of a my 1988 420SELit was not thesame wiring. Also it has a 10 disk cd changerand I am thinking the one that came with it is not compatable with the cd changer. Or is there aanti-theft security code that needs to be reset? Any help would begreatly appreciated. I have also noticed that theCD changer sounds like its shuffling disk continusly, it doesnt stop until I pull thecd holder out.