My blower died, so I pulled the AUDI Bentley manual and started to
diagnose the problem. According to Bentley flowchart, the blower was
broken. I ordered a used blower for $70 from Audi Shokan and spent
4 hrs replacing it. It worked! The blower was back on line. I was
really happy with my job since it had saved me from a few hundred
dollars (It would have costed me close to $300 if I had had it done
by an Audi dealer). UNFORTUNATELY, the blower stopped functioning
a few days later.
I pulled the Bentley manual again and started to examine the system. The
guide led me to believe that the blower controller (which you described
as the circuit board with a couple of heat sinks under the plastic shroud
in the hood) was broken. I double checked my conclusion, checked all
wires and finally I came to the agreement that the blower controller had
to be replaced. I ordered the part from AUDI Shokan, and I installed it.
Guess what? It ain't solve the problem!
At that point I was so frustated, but I had gone too far to give up. So,
I took the system apart, checked all the wires and connectors, verified
the voltage readings at the connecters of A/C programmer (the one above
your tape deck), flap controller (the one behind the glove compartment)
and the thermostat. I found anomali on one of the pin at the A/C programmer.
In a test setting it wasn't producing the specified voltage. I forgot
exactly which pin, but what I remembered that it was too low. So, I figure
this must be the real problem . I checked the price and it would cost me
$125 (used!). I had spent too much money on the climate system. So, I
decided to directly wire the blower. Now, I have a switch that turns on/off
the blower. I still control the flaps and temperature from the A/C programmer.
I forgot to mention that two years ago I had a problem with climate control.
The A/C compressor didn't turn on. At that time I was naive and brought the
car to a dealer. They said the thermostat was broken and charged me $125.
While I was working on the system to fix the blower problem, I found out
that the thermostat was badly rusted. For two year time, I didn't seem
that the Audi dealer replaced my thermostat as they had claimed!
I really hate the DELCO climate system on our Audi. I'm glad that they
get rid of it and build their own. I don't think it is worth my time
to fix every single bug that comes with the system. It would be ideal
if I had time and resources to build a simplified climate control. Just
a few buttons that will turn on/off the blower, A/C compressor, and
change the directions of air flow. So, becareful, don't be too quick in
making a decision, and prepare to spend LOTS of money! :-)
This experience taught me not to buy Audi that has delco parts. Once I was
offered a good deal on Audi 90, but I spotted the power seat control. It
was DELCO! So, I back off.
Good Luck and Welcome to the Jungle of Delco Climate Control!
----- Begin Included Message -----
Thank you everyone for all the responses to the OXY sensor and water
leaking problems of my friends '84 5000S. Alas, another problem has
just arisen. The car's climate control unit has decided to stop
working. All the buttons on the panel are switching, but the fan does
not blow. BUT, it is not the fan motor, because it does run when
hotwired to the battery. After tracing the wires around, my friend
suspects the AC-Delco board just under the plastic shroud in the hood.
It's the circuit board with a couple of heat sinks on it. He has had
grounding problems with this board. Does this sound familiar to
anyone? Any ideas what the problem might be and/or how it can be solved?
----- End Included Message -----