Welcome to the forum
Let’s see if we can get you on track for your camping trip. What brand tongue jack and awning? Some water heaters will have a switch on the outside, lower left corner that needs to be on for the element to work, and it’s upside down on purpose. Your door may have “friction” hinge that’s supposed to keep the door in the position you set it. You can leave it plugged in as long as you check the water level in the battery often.
Sounds like your selling dealer didn’t really give you a good walkthrough.
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2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.