We have just brought home (new to us) a 2015 Cruiser Aire fifth wheel. Plugged it into our outside 20A outlet and it trips the GFCI. I have isolated the problem to the 15A microwave circuit. I have u...
The slide would definitely be suspect haha... all those cables move back and forth with the slide... You should be able to check the wiring for being frayed or something...
Plugging in the tester where the microwave plugs in will show an open ground perhaps... Maybe you have said that already haha...