I have a 2007 A6 S-Line with a center panel ignition switch in addition to the traditional key ignition. I am having 3 issues that both emerged tonight:
1) the ignition button suddenly is not responding - I used the stop to turn the car off and 5 minutes later needed to go back out and the start would not work - the key works and the unlock buttons on the key fob work (with one strange exception - - Item #2) - so I don't think it is the battery in the fob. I have my foot on the brake and the button just does not seem to depress as much as it usually does but there is absolutely no reaction from the electronic system.

2) when I use the electronic fob to lock the doors - all of the doors lock EXCEPT the back passenger.

3) The drivers side convenience lock (button under the door handle) is unresponsive as it the unlock detection that unlocks the drivers side door when you approach.

They all seem connected to the key fob - is there a transponder system or fuse that may be out?

Any thoughts? Not sure the issues are related of if i just discovered them at the same time.