Hi there, the indicator your seeing is for your windshield washer fluid. Your tank is pretty low to the ground, there's a chance you cracked it and is empty. I scanned my manual with the page with that indicator for you to look at. Also, listed a website where you can order owners manuals, and a website with a lot of good info on audi's.
Ti Kan: Audi
AUDI Service Publications-Order Form
