I dunno, but I have one too ('85 Westie GL, 4spd manual).

I've heard rumors of a TDC sensor mounted at the flywheel for use by the
(now certainly obsolete) dealer diagnostic equipment, maybe this is where
it hooks up?

At 02:06 PM 6/1/2005 -0700, roger sisler wrote:
>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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