[200q20v] A/C relay jolts ECU, Pops Bose

[Mike O'Donnell]

Kneale,

I just replaced the same relay because my A/C was "ON" in all climate
control settings including ECON.  It is the last relay on the right side of
the middle row; at least on my car.  The part number I used was 443 919 578H
and it was $39 from the Parts Connection (thepartsconnection.com).  Prior to
replacing the unit I replaced the diode per instructions on Scott's site,
but was unable to rectify the problem, and just bought a new relay.  Best of
Luck.

Mike O.


----- Original Message -----
From: Kneale Brownson <knotnook at traverse.com>
To: <200q20v at audifans.com>
Sent: Monday, September 04, 2000 6:03 PM
Subject: [200q20v] A/C relay jolts ECU, Pops Bose


> 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?
>