I have a 1996 Audi A4 Quattro, stick, but as of yesterday the battery and brake light would stay on. After a bit of driving the gauges would all quit working and shortly after the car would die. I got a new battery, as the one in it was from November of 09. I stopped at O'Reilly's and got my alternator tested and they said it was good but had a low charge of 45%. I had to drive two hours to get home and the car died on me 15 miles from. I'm wondering if it's the alternator or if it would more likely be the V-Belt as the owners manual says

 

I think you can take a code scanner to have a check, or if you take your car to nearby repair shop.