I've got two ceiling lights in my upstairs hall, both controlled by two wall switches. One light doesn't work but it's not a bad bulb. I suspect it's on a circuit that isn't working, either, but I'm not sure.
I plugged in one of those little circuit tester gizmos, that shows various patterns of yellow, red, or no lights, indicating various conditions. I plugged it into a 3-prong socket I THINK is part of the same circuit the bad ceiling light is on, and the gizmo says "open ground".
What is it telling me? What should I expect to find, if I take the plate cover off and examine the guts of the wall socket?
I'm a pump/pipe/valve guy, not a wiring guy, so keep it simple if you answer me, please
I think a switch is something that pinches the wire and stops the electrons from moving through it!