I'm having some issues with my 2002 a4 1.8t quattro tiptronic. Now keep in mind that the car does have almost 260k miles. It started yesterday when I went to turn off the car....it wouldn't turn off. You could take the key out and it would stay on. Then I figured out that if you open the driver's door, it will shut off just fine. I think there may be some short that I can't see. I have already replaced the ignition switch thinking it was that but is hasn't gone away. If you open the driver's door a little nothing happens, but open it a little more and the lights come on, the radio turns on, the fuel pump primes. What the heck is going on?! Is there some door sensor that has shorted or something? I'm at a complete loss. Any guidance would be greatly apprciated

 

I would look at the door/ interior light switch. I have heard of cases where a dead short on the cars frame could cause the "ghost in the machine" type stuff your seeing. Maybe try locating the fuse for the dome lights that activate when you open the door and remove that just to see. If the car rides and drives fine then I would look at all the accessory systems and remove the fuse for each one indevidually and see if any one of them solves your problem. Just ideas. I hate electrical problems.

 

We recently discovered that when you jiggle the wires between the door and the car (the ones in the rubber accordion rubber) that we can recreate the problem. So we believe that it is maybe a wire that gets pulled or is loose in the connector there.

 

It seems strange to me that a door switch could cause such havock in the circuits but I have heard its common.