reverse polarity light glows when plugged into shed power

[desertug]

I searched this discussion and posts refer to Honda generators. My boat doesn't have a generator. I don't think it was glowing when I first hooked it up but both of them are doing it now the AC panel and the isolator behind the seat in my R31S. I am an electrician and know what it means, I took the plug apart it is wired correctly i miss wired it and the AC panel light came on full bright when re energized. My household tester says there is no reverse polarity in the cord coming to the tug or on the tug when everything is plugged in I have two different adapters and both yield the same results.
Anybody out there seen this???

 

[Cessna172]

I asked this question to the factory and was told it is due to the Honda generator not being a grounded power source.

 

[desertug]

I FIGURED IT OUT 😀 if you have a 110 source that has a high resistance ground connection the reverse polarity light comes on I don't think it harms anything, I think it is just putting a small voltage on the neutral that lights the light. I changed the hook up to a more direct path than the 220 split drop that the boat was plugged into and voila the light is out completely. 🙂