How to find wire in a wall - to put a switch
I just bought a 30 year old house with a 15-foot high ceiling fan and light combo in the bedroom. There is no mechanical switch to control this fan/light. There is just an infrared remote control. The trouble is the light has developed the nasty habit of turning on all by itself, sometimes at 4 AM. I have to sleep with the remote close at hand to be able to turn it off quickly and get back to sleep. I don't think anyone is trying to drive me crazy by shining another remote through my bedroom window. I think the electronics in the ceiling have just gone flakey.
I would like to install a switch in the feed to this fan/light. The power runs through a wiremold along the ceiling and then dives into the wall. I have not found any switch that interrupts this feed, except for the breaker at the service entrance, which also controls some other outlets, so I don't want to cut it off there. If I knew exactly where the wire was in the wall, I wouldn't mind cutting into the drywall and installing a box with a switch. Is there something I can rent or buy for not too much money that will detect the wire - perhaps by an injected signal that can be picked up at short range? Or should I try to interrupt the feed up at the ceiling wiremold?