In article ,
"John Grabowski" wrote:

If the fixture is working then leave it alone. If the fixture is not
working remove it and hook up a rubber pigtail socket and bulb to the
ceiling wiring to check it. Stop using your voltmeter. I'm guessing that
you are checking the voltage between the neutral with the fixture lit and
the grounding conductor.

I think this is scary advice. The OP seems a bit out of his depth here.
He would be better advised to hire a competent electrician to get to the
bottom of this situation. There may be a perfectly rational explanation
for the voltage between N and G, but it also is an indication of a truly
unsafe condition.

When my son bought his house a few years ago, I found out that the
electrical system was upgraded by using grounding receptacles. Some were
found in the bathroom. The only problem was that no grounding conductor
was present. Everything would work as well as could be expected until
you become the grounding conductor. There probably are many such gotchas
almost everywhere.

Bill

--
Private Profit; Public Poop! Avoid collateral windfall!