When the battery goes dead, is it common for the radio illumination to come on....
 

and stay on, even when the key is out of the ignition? My wife's allroad just started doing this the other day right at the same time the battery died.

Common? No. But all kinds of weird stuff can happen with a weak/dying battery.

Perhaps the radio illumination is causing the dead battery???
 

The radio illumination should go off with the rest of the stuff when the car is turned off.

The radio illumination glitch only happened after the battery started dying...
 

The battery seemed to be having some trouble turning the engine over on cold starts for a couple of days before the illumination glitch, so I think the battery voltage was creeping lower over a couple of days, then finally started causing electrical weirdness.

Now, with the illumination constantly on, its definitely draining the battery.....

I have an appointment to bring it in tomorrow.

Brian - what did the dealer diagnose? I had the same problem, now my radio illum don't work after
 

replacing the battery

It's at the dealer today. I'm pretty sure its a dead battery, but it could be the alternator, too..
 

I'll keep you posted. Interestingly, though, when I jumped the car this morning to get it over to the dealer, the radio illumination issue was gone. Everything worked normally (except that I had to jump it to get it going).

It was a bad battery. $140 + $45 labor.