If you have a detachable power cord, I would check it first, most likely place to develop a short. If that is ok, I would shut off the main breaker in the trailer, plug the power cord in and see if the breaker in the house still trips. If it does then, the problem is between the plug on the side of the trailer and the trailer breaker panel. I'm not sure how to access the back side of the plug. Finally, if the house breaker doesn't trip, the the short is in one of the individual circuits inside the trailer and you will have to determine which one is the culprit.
Texas Baptist Men-Retiree Builders member since '01
13 Silverado 3500HD D/A, 2wd CCSB srw, custom RKI bed
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