Re: Climate Control Fan inconsistant 88 5000

["Fred Munro" <munrof@isys.ca>]

Hi Ben;

    It is likely that the brushes in your HVAC blower fan are worn out and
that is why you are getting intermittent operation. These fans are running
whenever the car is running, and the brushes typically last 7-9 years. The
cure is a new blower motor.
    You can check the brushes by removing the plastic plenum cover (covering
the area between the base of the windshield and the top of the firewall) and
pulling the cooling hose ( a right angle soft rubber hose) off the blower
motor. The blower motor housing sticks out of the right hand side of the
heater box. If you look down the hole opened up by removing the hose, you
will see the blower motor top brush. If the shunt (the braided copper wire
attached to the brush) is at or near the bottom of the slot in the brush
holder, the brushes are worn out. Pushing down on the brush with a
screwdriver sometimes restores contact with the commutator and temporarily
brings the blower motor back to life.
    If the high temp warning light is coming on and you can't hear the fan,
it is probable that your rad fan is not coming on. Since the rad fan runs
when the AC is on, the fan & first stage relay is OK. The problem may be
with the thermoswitch which senses engine temp and activates the fan relays.

HTH

Fred Munro
'91 200q  272k km
----- Original Message -----
From: <BSWANN@arinc.com>
To: <munrof>
Cc: <quattro@coimbra.ans.net>
Sent: Friday, April 16, 1999 5:11 PM
Subject: Climate Control Fan inconsistant 88 5000


>
> Greetings,
>
> I just replaced the radiator fan in my 5000 Wagon which had seized up.
>  I hope this was done before any wiring damage.
>
> Now I notice that my climate control fan doesn't operate on demand.
> When I first start up with engine cool it works - sometimes.
>
> After the car is warmed up - can't get it to operate.  I can hear the
> compressor clutch kick on if I set it for AC and if set to heat can
> hear the vents set for heat, etc. just the fan doesn't go on.
>
> Other notable symptoms:
>
> Not sure if radiator fan goes on during normal driving, as a couple of
> times was stuck in gridlock, the temp gauge started to rise but I
> never heard radiator fan kick on and the warning light came on just
> before I would get onto the highway and cool back down again.  The
> radiator fan kicks on with the AC, and afterrun works.  Possible
> Resistor Pack problem?
>
> I looked at a generic wiring diagram for AUDI 5000's ( havent got a
> Bently yet) could not find the climate control fan, but noticed the
> following:
>
> Seat Belt relay has leads going to
>    Climate control
>    Cruise Control (not working )
>    Under Hood light (not working)
>    Antenna??? (never can get good reception)
>
> Is it possible that this is the source of this anomoly?  Where is this
> relay?  By the way I did check all fuses.
>
> I'd appreciate if anyone can provide me with some additional clues.
>
> Thanks,
>
> Ben Swann
> '85 4KSQ
> '86 5KCSQT (parts or restore?)
> '87 5KCSQT Wagon
> '88 5KS Wagon
>
>