Originally Posted by Old-Biscuit
Check on/under tongue for a small DC Circuit Breaker
Battery POS Cable goe to/from that CB before going Inside the trailer to DC panel etc
Could have tripped...small reset button on the side of box
Keep this 12V breaker in mind for future reference. Learning about this cured my power issue shortly after buying my TT. A simple press of the tiny button and all my 12V came back.
Coincidentally, on my 1st spring camp a few weeks ago, the same trouble occurred. I immediately went to this breaker, but found it was OK. On a hunch, I checked the nut that connects all the cables on the stud and found that it was loose. I didn't have a wrench with me so I finger tightened it (it was blowing rain and sleet at the time) and once again my 12V power was restored.
When I got the rig home I tightened both nuts. I also found that some other nuts, the ones that hold the trailer box to the frame, were loose. I went around a tightened all of those, too. I suspect towing miles from the nearest pavement shakes these things loose, and I've learned to check fasteners more frequently.