battery not charging

My alternator in my 83 CJ7, 258 engine, is not charging the battery, this has been an intermittent problem the past few months. I have now used 2
different alternators, and had both of them bench tested. Also I have a new battery (6 months old Optima), and new battery cables. Fan belt is adjusted properly and spinning the alternator. My next guess is that whatever wires meter the battery voltage and tell the alternator when to turn, or however that system works needs to be cleaned or replaced. Can someone explain to me how this charging system works?
As I see it there are 4 connections to make this work.
Ground - The alternator grounds it self through the engine Positive - the post coming out of the back of the alternator, connects to junction mounted on fender Side A of plug - Also a positive wire ( also a red wire) that connects to the positive post as well, then continues to fender Side B of plug - This is a thin gauge wire, black in color, that ties into the wiring harness, and probably up through the firewall of the jeep. What does this wire do? where does it connect to?
Any ideas?
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That thin wire should be the "sense" wire that tells the voltage regulator at what rate to charge the battery. It normally comes from the instrument cluster, usually from one side of the the Alternator light, and then feeds the regulator with the voltage from which the regulator determines when to turn the alternator onto its charge mode.
Jerry -- Jerry Bransford PP-ASEL N6TAY See the Geezer Jeep at http://members.cox.net/jerrypb /

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Ignition switch "on" position. God Bless America, ill O|||||||O mailto: snipped-for-privacy@aol.com http://www.billhughes.com /

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Are you saying that the one I have called "Side B" feeds into the ignition switch?

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