Re: LONG bypass exterior ambient temp sensor?

[Elliott Potter <epotter@abraxis.com>]

James Marriott wrote:
> 
> Elliott Potter wrote:
> >
> > James Marriott wrote:
> > >
> > > Elliott Potter wrote:
> > > >
> > > > Now that winter is arriving again, I have another odd irritant/endearing
> > > > feature of the Audi climate control to b*tch and moan about.
> > >
> > > > The car is a 93 90CS, with an automatic climate control.
> > >
> [...] 
> > > > The irritation is that when it gets below a certain temperature outside,
> > > > the A/C won't turn on.
> > >
> > > The reason for this "malfunction" or "deficiency" is that below about
> > > 35-40 dF (2-4 dC) there's pretty much no moisture left in the air. If
> > > it's not there, why try to remove it? Also, especially if it's a 134
> > > system, it is pretty helpless at these low temps by design. Not Audi's
> > > fault, just a fact of the thermodynamics.
> > [...]
> > The other reason I want to disable the sensor is that Atlanta is also
> > the Land of Deisel and Burning Oil, and recirculate won't work unless
> > the A/C is on.  Just a little annoyance, you know...
> 
> Igor, any ideas how to rig this? Perhaps a fog light switch (any blank
> spots on the dash?) wired to fake either the AC or the recirc into
> working? Recirc, of course, in the winter will fog the windows in about
> 10 seconds, BTW. You DO NOT want the AC running when it's below ~38 dF,
> or you'll just freeze up the evaporator. The only way for the system to
> transfer any significant heat is for the evaporator to be much colder
> (like maybe 20 or 50 dF) than the air. At these low temps, the
> condensate will freeze on the evaporator rather than drip off like in
> the summer. Typically this just cuts down the efficiency (heat
> transfer), but if you condense enough, you can ruin the evaporator, like
> blowing a coolant freeze plug.
 
Well, this definitely looks like a project, but one that will have to
wait until I get proper wiring diagrams and figure out how recirc.
works.  What I would absolutely *love* to do is muck around with the CC
computer and find some way to trick the recirc. into thinking that the
A/C is on, but that's a project for another day...

> > > > Anyway, does anyone know where the exterior ambient temperature sensor
> > > > resides, or how to disable it?  Also, what would be the side effects of
> > > > disabling it?
> > >
> > > On the 4kq it's under the cover behind the firewall (under the hood,
> > > like with the wiper motor, and on the right side). Yours is likely the
> > > same place. Mine is a little, black, marble-sized component with two
> > > wires. Dunno if it's normally opened or normally closed. The "fix" for
> > > mine would be to either disconnect or short the wires, depending on
> > > which way it's configured. YMMV.
> > [...]
> James

Well if I look out my window right now I can see a whole parking lot of
cars whose air conditioners work in the winter (so I assume) but I'd
rather not risk breaking lots of expensive bits of my car so I think
I'll cool off (arrg) on fiddling with the temp sensor, at least for now.

Elliott