My "radio" (control unit in MB-speak) went south while attempting to do a GPS map update (yes, using a cheap eBay set of discs - live and learn). I think the root cause of the problem is that the CD/DVD player device in the head unit just failed, probably after a decade or more of little or no use.

Anyway, after a months-long search, I finally found an identical head unit on eBay (there is a bewildering number of options, and I wasn't willing to try "something just a little bit different").

Since both are set up to work with navigation (as well as the other options, including the odd but nice PCMCIA chip reader). When my old head unit failed, the GPS update was in mid-stream, so of course now the GPS doesn't actually work (and strangely, neither does the PCMCIA reader).

Will my new head unit include the actual GPS files (so my GPS will work when I swap out the head unit), or is the head unit just the way that they're downloaded into a hard drive or memory chip somewhere else in the vehicle?

The maps are stored on the hard drive in the head unit so you should just be able to plug and play.

The hard drive is in the head unit aka radio, control unit)?

Yep it's underneath this cover on the bottom of the head unit.

Thanks! I really did scour this group and the 'net in general, and couldn't find this info anywhere. Hopefully this thread will show up for those doing searches for this info in the future.

Now all I have to do is hope that the previous owner of my "new" head unit upgraded their GPS map files... ;-)