View single post by Paul Prinsen
 Posted: 04-27-2006 12:34 am
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Paul Prinsen

 

Joined: 11-20-2005
Location: Medford, Oregon USA
Posts: 19
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 Most surefire way to get it right is to know what make+model the alternator came from, and get a hold of the original wiring diagram. If that is not possible, I have some suggestions:

B+ is battery. D+ or one of the thin wires is the charge indicator light. Housing is ground. If you have one more thin wire, this could be an AC output for engine management or RPM indication, and should be left unconnected. The large black wire may be used as the source for the field (most likely) or a seperate ground (not likely).

To test, you may want to put a big 12 V bulb (headlight bulb) between the "big black wire" and the battery + terminal. If the bulb glows dim, and the system charges, that wire should go to battery plus or your ignition + terminal. If the bulb glows bright, the black wire is a ground, and the bulb prevents a dead short.

Hope this helps!

Paul