Stationary Uncoupling
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2003 Volkswagen EuroVan, 2002 Volkswagen EuroVan, 2001 Volkswagen EuroVan, 2000 Volkswagen EuroVan, and 1999 Volkswagen EuroVan. However, it is still accessible from the selected car via links, so may be relevant.
The transmission control module hydraulically shifts to Neutral, uncoupling the engine, when a driving range is selected, the vehicle is stationary and the brake pedal is applied (e.g. at a stop light).