[200q20v] A/C relay jolts ECU, Pops Bose
knotnook at traverse.com
Mon Sep 4 22:03:40 EDT 2000
Since it's Labor Day, I decided to Work on the 200q20vt, tackling, among
other things, locating the A/C compressor clutch relay artfully hidden
behind the kick panel beneath the instrument cluster.
This is in search of a solution to the problem of the car suddenly
hesitating and the radio issuing a popping noise when the A/C is turned on,
or, indeed, when any HVAC setting other than ECON or OFF is selected.
Earlier advice from the list indicated I needed to find a relay with the
part number 443 919 578. Being the orderly sort, I started pulling the
visible relays beginning with the lower bank and nearest to the door. The
last relay in the upper row bore the # 443 919 578F. With the engine
running and the A/C turned on, I could feel that relay click occasionally.
The earlier advice also included a notation that the Audi TSB "fix" for
this syndrome is to replace the relay with one numbered 443 919 578E and
a Zener diode # 443 298 008, and that this $125 parts cost could be avoided
by replacing a burned diode within the relay with "any Radio Shack 2 amp,
50 volt or better diode (not Zener)."
Well, the 443 919 578F that I found had no discernible burned diode inside it.
In additional searching, I found a note from Scott Mockry last March that
there is an "add on zener diode kit 443-298-008 for the A/C compressor
magnetic clutch wiring harness" for cars earlier than November 1990 and
with VIN below 024295. My car was built in July of 1990 and has the VIN
006235, so I presume the add-on kit is what I need.
Does anyone know whether the kit amounts to a replacement relay I can just
plug in? Is this the $125 part?
I'd prefer a $2 diode from Radio Shack, but I can't see where it would go
on my existing relay. Does the "F" on the end of my relay part number mean
I've got the wrong relay to fix with a simple diode?
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