I purchased a used A8 - like the car, but hate the frustration.... today, after driving 3 plus hours from home, I got back in the car, put the switchblade key in the ignition, went to start the car.... heard some clicking mechanical noises (not like a dead battery motor won't turn but something behind the ignition switch) and now the car does not respond - at all. Furthermore the key does not want to pull out of the ignition. Jiggling the shift lever causes a beep and a message about making sure the car is in Park - and then I can remove the key.
The FOB buttons do not unlock or lock the doors. The panic button does not cause the alarm to go off.

Last week I did see the faulty ignition switch idiot light pop up a few times - and shut off while the car was running - and I had not seen it since.

It has a brand new battery. The locks, lights, etc from inside the car (not the FOB) work.

Any ideas?

I had to rent a car to get home.