Last evenening we noticed a high pitch sound coming from our Jayco TT.
I had it parked, still hooked up to the TV for about 3 days after a trip. I had removed the 30 amp fuse between the TT battery and the TT to keep it from draining the TV battery - that didn't work by the way. I removed the carbon mono and smoke detector units. The sound continued and was at the other end of the trailer from the detectors toward the ceiling. I pushed the button for the slideout and it stopped immediately, but started again the next morning. I don't know what would be humming like that. The TT battery had enough juice to operate the tongue jack. Refridge, AC, heat, fan were all off. Any ideas or has anyone had the same situation? My guess it's electrical. The only control near the sound is the themostat but the sound was not coming from the unit when I put my ear to it.
I thought about that, but the motor is 10-12 feet away and on the opposite side from the sound. I started thinking that trying to use the slide, or any electrical load, pulled the last bit of juice from a capacitor or something like that. (I'm not an electrician, just know enough to get myself into trouble usaully) Since I removed the 30 amp fuse, there should be zero amps getting to the trailer. Or am I mistaken on that and the trailer battery is still included in the circuit?
My previous trailer made a high pitch whine when the TV brake pedal was depressed. It was the sound made by the electric trailer brakes. I know you said the sound was coming from the ceiling, but sound sometimes has a funny way of travelling through walls. Wouldn't hurt to check it out.
Does the sound occur when you disconnect from the TV?