http://shakti.trincoll.edu/~sritchie/Passat_fuse_panel.html This should answer all of your questions about the fuses, what they are for and what amprages to use.
how do you remove a 1999 vw passat radio
Open the driver's door and there will be a removable panel on the side of the dashboard (there is a small hole to help you to open it). The fuses are located under this panel and there should be a very confusing diagram on a card to help you.
VOLKSWAGEN PASSAT 1998-ON 5x112
Parking and dash lights also on this circuit - do they work? Check fuses Could also be a bad headlight switch
Relace the rear window.....the heating coils are imbedded into the glass....or check the connections and trace the wire,check the fuses before you go that route.
The Horn on a Passat is operated by pressing the centre of the steering wheel.
My 1999 Passat has 225000 miles and still going strong
If you have a 1999 Passat V6, the coolant temperature sensor is located in the lower radiator hose.
http://www.tobio.info/passat/howtos/passat_air_filter.html
change the timeing belt every 105000 kms on 1999 passat 6 cylinder 2.8 engine
Fuse #24
On my 1999 Passat GLS, the fuse panel is on the left side of the dash, facing the driver's door. Use a screw driver at the bottom of the cover panel to pry it off and expose the fuses. The fuse panel cover has a fuse puller and card that diagrams the fuse locations with their purpose.