Re: Aux. Fan - 87 4kq

[Luis Marques <marques@rtis.ray.com>]

"Mark L. Chang" <mchang@ece.nwu.edu> wrote:
> Regarding my last post about the Audi Gods being vengeful, I just have
> a few questions about the auxillary fan in my 87 4kq that will not
> shut off... from the moment I turn the key to the "ON" position (not
> cranking yet), the fan whirrs...
> 
> What should I check?  I've pulled the relay and am about to dig up the
> multimeter to see if we've got a short.  I know the control is a
> thermoswitch somewhere, but where?  Could someone point out where it
> might be so I can see if there are loose wires?

When the ignition is on, the radiator fan is controlled by the thermo
switch on the bottom of the radiator, or by the A/C high pressure
swtich, which I think must be in one of the A/C lines in front of the
radiator.

Disconnect these switches one at a time and see if the problem goes
away.  Most likely you just have a defective switch stuck closed and
must replace it.  I hear the A/C switch can be pricy to fix, so you may
want to just crank up the volume and ignore it if this is the case.

HTH

Luis Marques
'87 4kcsq