120 Volts Before Wire, 18 Volts After
I have an outlet that recently stopped working. I have traced the problem back and this is what I have found: The line coming in at one end of a crawl space reads 120 volts AC. When I directly connect the romex that feeds the outlet on the other side of the room (the romex goes under the floor through a (currently) damp crawl space. The wire reads about 18 volts at the far outlet end. I have this connected directly with no other connections between the point where I know it reads 120.
Just to be clear - line from circuit panel reads 120 volts at the point where I use wire nuts to connect it to about a 25 foot piece of 12GA romex wire. At the end of the 25 foot piece the voltage reads 18 volts.
The two wires have been joined in different ways - with an outlet and various wire nuts, but I get a consistent reading of just under 18 volts at the far end.
What Could cause this?