I went through some voltage stabalizer troubles some time ago. The things
kept blowing on me at the rate of a about one every 2 months. They would
blow in two stages. First something would happen that would cause the gages
to read about 25% higher than they should. This state would hold for a
couple of weeks when the second stage occured that took the gages out
compleatly.
    What appears to be the final cure was accomplished by mounting a heat
sink under the chip. I got the heat sink from Radio Shack. Installation
required some bending of the sink to make it fit and I also added a thin
layer of Heat Sink Compound.  That was about 15 months ago and things have
been holding fine.
    I also had the middle leg hanging in the air. It turns out that the
middle leg is a ground. So is that lug you put the screw through. You ground
the chip when you screw it in so the middle leg is redundent.

----- Original Message -----
From: John Y. Hung <jhung@ENG.AUBURN.EDU>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, May 20, 1999 2:20 PM
Subject: Re: voltage stabilizer

> The typical "3-pin" regulator has an input pin, output pin, and ground
pin.
> On many voltage stabilizers, the mounting tab is equivalent to one of the
> electrical connections.  Are you sure nothing is broken off?
>
> John Hung
> Auburn, AL
> '84 GL (w/ A/C and std. trans)
> (electrical engineering professor)
>
> >Date:    Tue, 18 May 1999 21:16:10 -0700
> >From:    Valued Cutomer <ned@DIRECT.CA>
> >Subject: 84 voltage stabilizer
> >
> >My friend's vanagon is an 84 (US model with a/c, std trans)that has
> >recently overheated due to a broken hose off the right cylinder head.
She
> >asked me to look into the situation and have since replaced both heads.
> > The van is running fine but... no temp gauge or led and no fuel gauge.
I
> >looked at the Bentley at the library and looked at the voltage stabilizer
> >as a starting point.  The photos show all three pins connected to the
> >printed circuit board (foil).  This is what you would expect of course
but
> >when I went to check hers out only the two outer pins are connected.
There
> >is no accomodation for the center pin (ie. nothing is broken off).  I
> >measured battery voltage across the two pins which was almost 12 V.  Does
> >this mean it is toast and not dropping the voltage to 9.5-10.5 like the
> >book says or does this particular stabilizer supposed to just pass
battery
> >voltage to the diagnostic circuits? I talked to VW here and they haven't
> >seen a stabilizer setup as I have described.  Has anyone seen such a
thing
> >and where would I get the replacement stabilizer if it needs replacement?
> >
> >ned  (too many vw's to list)