A/C Clutch Relay Questons

TooManyAudis at aol.com TooManyAudis at aol.com
Mon Mar 29 23:52:03 EST 2004

I evac'd and recharged the a/c system on my 200q yesterday.  All works well, 
with the climate control doing everything right (airflow goes to the proper 
vents and everything!), except that the compressor runs on econ and off.  In 
searching the archives, the likely cause was a shorted diode that connnects 
between #30 and #87 on the relay.  Sure enough, there was continuity between those 
two pins, and when I cut one of the diode leads, the relay acted "normally" 
being open in the normal condition and continuity between the two pins when I 
manually closed the relay.

So far, so good.  One of the writeups mentioned replacing the defective diode 
with a Radio Shack 50v 2Amp diode.  That would be fine, except my radio shack 
only had 1 amp and 3 amp diodes from which to choose.  So, I got one of each. 

The question is, which one to use?  I am thinking the 3 amp, but I will defer 
to those more knowledgeable on the topic.  Also, the diode is directional.  
What is the proper orientation?

This will be the first time doing a hack job on a circuit board, although I 
have done the basic soldering for universal oxygen sensors many, many times.  
Any tips for soldering/unsoldering?


-- Tom

91 200q
88 80q
92 VW Cabriolet

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