You have dirty contact points on the cutout relay in the regulator. There's just enough resistance across the points that some of the charging current is trying to flow through the idiot light, making it glow slightly. Disconnect the battery wire from the regulator, take the cover off, and use a thin slice of index card stock to rub between the contact points. DO NOT USE EMERY CLOTH! Any abrasive at all will cause the points to stick by setting up roughness on the points. They open and close with a slight wiping action to be self-cleaning, supposedly. The cutout relay is the set of points right behind the Battery terminal, the one with the points open anytime the engine is not running. It won't hurt to burnish the other two sets of points while you're in there, but don't create any scratches on the contacts.
Jerry

Last edited by Hotrod Lincoln; 12/18/2008 9:00 PM.
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