Re: 5KS CLIMATE CONTROL GREMLINS (oops, kinda long)

[EICHSTEV@aol.com]

In a message dated 96-10-01 17:15:14 EDT, you write:
>
>The bad news:  The PC board looks like it has no more than $10 worth of 
>parts on it, but it cost $300!  Gulp.
>I was almost tempted to try and fix the board myself...

BTDT.
I've repaired more than fifty of the things and know them pretty well.  There
are basically three areas of failure on the '86-'88 5k HVAC programmer (box
w/ vacuum lines, bowden cable and electrical connector behind the glove box):

1.  Poor solder joints on the vacuum solenoids ultimately fracture resulting
in improper air distribution.  (Air comes out the wrong ducts.)  A visual
inspection of the solder side of the board will usually show black rings
around the defective solder joints.  They will most likely be loose also.

Common symptoms: 
a: Air shifts from heater ducts to defrost for no apparent reason.  
b: It works if you hit it!?  
c: Can't get air out of center vents.

Solution:  Simple, remove old solder, scrape off corroded terminals, and
resolder being careful not to get solder where it doesn't belong.

2.  Vacuum solenoids contaminated with oil.  A visual inspection will show
oil in the lines inside the programmer.  The solenoids should rattle if you
shake them, if not oil has caused the rubber seals to expand and not
function.

Symptoms:  Similar to poor solder.  Usually the system will be in the default
state with air coming out the defoster ducts w/ a slight amount coming out
the heater ducts.  (The default state will also occur if there is a leak in
the vacuum supply.)

Solution:  Replace the programmer and install filter in vacuum supply line.
(There is an Audi TSB on this matter.)   Individual solenoids can be
replaced, but if there is oil in the system, the problem will re-occur.

3.  Gear reduction motor fails, causing improper control of temperature
control flap.  (Air temp. coming out vents is wrong, A/C compressor working,
heater valve OK.)
 
Symptoms:  Bowden cable does not move, or does not move to fully open or
closed position.  (This can be verified with climate control diagnostics as
listed in the Bentley manual.)  

Solution:  Sorry, replace gear reduction motor in programmer.  The internal
plastic gears strip and can't be individually replaced.

These are the top three failures I have found, with defective solder joints
accounting for about 80% of the problems. 

STANDARD DISCLAIMERS APPLY

HTH!

BTW, you should be able to find a good or rebuilt programmer for around $125.
 I know...   :)

Steve Eiche
Lakewood, CO
'82 Not So Ur q 3B2B