Check the Water Drain for Contaminates
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2018 Audi S6, 2018 Audi A6 Quattro, 2018 Audi A6, 2017 Audi S6, and 2017 Audi A6 Quattro. However, it is still accessible from the selected car via links, so may be relevant.
-- Open the glass panel all the way.
-- Drain the water from the guide rail near the glass cover -arrow- into a commercially available measuring container -1- out from the vehicle interior.
- Make certain that the water divides in both directions so that it can flow out again from the A-pillar and from in front of the rear axle.
-- Repeat the process for the opening on the opposite side of the vehicle.
NOTE:
If no water flows out from the appropriate areas, clean the water drain. .