I was under the impression that all the VW radios that had the little key
icon on the faceplate were the anti-theft variety, requiring a code to be
input after any power interruption. But I've now come across two of these
radios - a '91 and an '89 - that power up without requiring a code. Both
radios have in common that they have been cut off from battery power for a
long time. Could it be possible that if left disconnected long enough, some
little battery in the radio loses its charge and its secret code as well? Or
maybe not all the VW radios had this "feature"? I'd just like to confirm
this, because I'd like to install one of these code-less radios for a friend
and don't want to leave her tune-less should the secret code somehow decide
to come back.

Thanks,
Doug Fitz-Randolph
Freeport, ME
'90 Syncro, '86 Single Cab