Alternator wiring

[VW_Man_87]

Ok I have a 2 wire alternator and Ive seen people with the same one that has a ground wire on it. Is that ground wire needed and where does it connect to?

Thanks
Jeremy

[Marc]

The ground wire isn't really needed since the alternator should be in direct physical contact with the pedestal/engine. It's a legacy of the externally-regulated alternators, where it did serve a purpose by assuring that the alternator and regulator were clamped electrically, but on an internally-regulated alternator there's no need - about the only difference you might notice with/without it is a slight change in the warning light action, and then only when there was a poor ground path from alternator to engine and body.
If it were needed for the charging system to function it'd have to be the same gauge as the B+ wire.

[sideshow]

It's not needed, but I run a brown wire from generator's regulator bracket (body).