Bit of a mystery here.
We've got an outlet in our 2nd floor bedroom that I assumed was dead or disconnected. I poked it with my AC voltage detector to confirm — yep, nothing. I was wondering if maybe the outlet itself was mis-wired, so I went to the breaker box and turned off the 2nd floor lights (15 amp AFCI breaker) so I could safely open up the outlet and take a look.
Good thing I thought to double-check with the voltage meter before sticking my fingers in there. Turns out, now that the breaker for the rest of the floor was off, suddenly I'm getting current to this outlet! Confirmed that plugging a floor lamp in works, which it didn't before. Confirmed that turning the AFCI breaker back on renders the outlet dead again.
Any insights on what could be going on here?