Hello. I've got a 2001 A4 1.8t quattro with tiptronic that I can't get to start. It has 65k miles on it and it still has the original battery. I left a vanity light on one night, almost completely draining it. I've got it charged back up so that it is showing around 12.5v, but the car still won't start. I even tried jumping it, but still it refuses to start. The car is cranking really well, which leads me to believe that it is something else, but I'm still not sure. Prior to this, I have had no problems with the car whatsoever. If anyone has any suggestions, please let me know.

 

Hook up a Vag-com & see if you can talk to the ECU, you might have fried it with the jump start.