Questions Re: Fusing fan type 85

[Huw Powell]

>         I have a 1986 4000q that I want to fuse the radiator fan.
> Here is some of the relevant info that I found so far.

> >   the internal schematic of the fusebox used in most
> >   late 80s audis is at:
> >   http://www.humanspeakers.com/audi/images/fusebox.gif
> >    - about 115k and a large image tho.
> >   at E87L you will see the *unfused* terminal for the
> >   rad fan. (R/Bk wire, btw)
> >   right next to it, at E871A is the same switched
> >   circuit run thru fuse #5.  A good thing to change on your car.
>
> Since there is an unused fuse on the same circuit would the
> "good thing to change" be using that fuse location between
> the relay and the fan ?  What amp rating would be needed
> since at http://www.sjmautotechnik.com/cooling.html#fan
> I found these two statements referring to type 44's ?

> Do these amperages apply to the type 85's too ?

no. the type 44 fans have huge current draws compared to the little
cars...

Anyway, this is the "how to":

unclip and raise your fusebox enough to get at the bottom.  Find the big
yellow plug - the one with 8 pins, not 6, that is.  It is the thrid one
from the front, under the fuse side of the box.

Pull it down and out.  There will be a fat Red/Black wire coming out of
it, this is the one you are going to move.  It is at the front and
outside corner of the plug.

just a sec while I go get a spare fusebox and yellow plug...

ok, to pull the R/Bk wire & its female tab, pry out on the plastic
thingamie next to it on the yellow connector.  when this is "out" enough
the wire will pull out.

87L is the second tab in on the other side of the yellow thing, that is,
the rearward bank of slots, one step inboard from what is probably a
grey wire with red spots on it.

Push it up into this slot until it clicks into place.  Reinstall yellow
connector.  Now you need a fuse in position #5...

My '82 coupe fusebox picture in Bentley shows a 25A fuse, and that
sounds right.
If you want to experiment with smaller values, make sure they don't blow
before trusting them - the same way you will test your work:

with the key on, jump the terminals of the radiator temp sender (on the
bottom, outer rear of the radiator) with a screwdriver or by pulling
them off ans connecting them to each other.  The fan should run.  make
sure it does.  Now pull the fuse, it should stop.   "unjump" the sender
and replace the fuse.  You're good to go.

If experimenting with lower value fuses, repeat a few times at least to
make sure the fuse isn't gonna go with several cycles.  leave it on a
few minutes, turn it off/on/off/on.  Still ok?  report back to us... and
carry a spare 25A just in case it isn't big enough!



--
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/