If you are seeing 12 volts on a wire that is coming FROM the generator ground connection that wire is not connected to the ground properly.
You are seeing the generator as if it is a large resistor and the voltage is passing through the generator but cannot get back to the ground.
This voltage will not support anything because it is a very low current at this point.
A 12 volt test light connected to that point will NOT likely glow and taking a voltage reading at the same time may result in showing zero volts because the light bulb type test light takes the voltage to ground.
Clear as mud I know.
Follow the ground wire path and fix where it is connected.
Myron & Deborah
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