Don’t overlook the possibility of the heavy cable inside the battery terminal having a poor connection. I’ve seen a couple cables pull right out of the heavy lead terminal. Any fault in the charging circuit just described will result in the battery not being able to control the generator out-put voltage. Since the power for the lights is picked up at the cutout, any fault in the charging circuit will let the generator put out up to 40 volts, which will immediately burn out light bulbs.

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