It it a timing sensor for the dealer VAG box. It detects a roll pin on the back of the flywheel.

Dennis

----- Original Message -----
From: roger sisler <rogersisler2000@YAHOO.COM>
Date: Wednesday, June 1, 2005 5:06 pm
Subject: what is that parasite on the back of my altenator?

> You know what I mean, people w/ the pre 86 vanagons(maybe post 85
> also).Looks like a electronic hook up of somekind.It has 3 prongs
> inside. Maybe for  a dealer diagnostics machine.Never, never ,hear
> of anyone mentioning this device. Dont know where the leads go ,
> and cant find this on the Bentley wiring diagrams.Strange-if it is
> not in the 1000+ page Bentley, it must be--not of this world.........
>
>
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