Tech Tip No. 17
Originally published in the quattro quarterly
That's Not a Spare Fuse!
Those of you who have replaced a fuse in your Audi using a fuse
from the "spare fuse holder" in the fuse panel only to have the car no longer run, or run well learned the following lesson the hard way:
Some Audis have a fuse/relay panel located in a plastic box under
the hood below the front window. Some of these panels contain a row of about 20 fuses, plus an area nestled among the relays where 4 spare fuses are able to be stored.
Sometimes attached to this fuse/relay panel is a strip of auxiliary
fuse holders that may contain one or more fuses.
The empty fuse holders next to the fuses in use make it appear as if the whole row is intended for spare fuses, and that there are one or two spares conveniently left there for you.
They are not spare fuses. Usually they supply power to run the fuel and timing computer, and without them the engine will not run. Fortunately some cars have a red plastic cover over those fuses with the word "Motor" written on it.
The lessons: 1. Know which fuses are being used before
assuming that they are spare fuses. 2. Remember what you did and put it back as before if something else goes wrong.