Originally Posted by
pizzaguy
So you have the alternator completely disconnected from the car's wiring when you get these readings?
If so, I'd say you have one or more leaky diodes in the alternator.
No; not off the car, but that will be my next step seeing how everything points to having to replace it anyway. Seems removing it will be inevitable. I'm still going to test the siren batteries this weekend, regardless, before resting on the alternator diodes being the sole target. Who knows; it could be the diode(s) AND the siren batteries.
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