WARNING: This page is about a different car, the 2003 Volkswagen EuroVan and 2002 Volkswagen EuroVan. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Automatic A/C-Heater System Wiring Diagram (2000-01 EuroVan - 1 Of 2)
Fig 2: Automatic A/C-Heater System Wiring Diagram (2000-01 EuroVan - 2 Of 2)