Your refrigerator will most likely draw way too much current on 12v DC to be viable; the battery would be dead within hours. I would expect to use it only on 110v AC.
What is the make and model of the fridge?
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Closer pic of the switch?
Year of your camper?
EDIT: it also looks like the cushions should be pulled into the footwell a bit, and the back cushions sitting on the wood seat, not on top of the bottom cushion. Might save a thigh or calf from some scratches. Just an observation.
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It might help to know what your Tow Vehicle (TV) is. Many people put that in their signature.
Some TVs have separate trailer wiring fuses; my Tahoe has individual fuses for the trailer brake lights, left turn signal, right turn signal, etc.
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Do it in the shade if possible, and put a dark towel over your head and the body of the PuP. Act like an old-time photographer.
And it's not a pilot light, it's just very small. Never gets bigger than that.
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Will the lower panel raise and latch into the inside track notch? I don't recall if the lower panels are movable.
The bend in the panel frame is just that. You can remove the whole panel frame without tools, and repair it if you can find similar parts from a screen/storm door. Might need to...
I'd clean out the latch with a liberal amount of brake cleaner and let that dry. Then use a teflon lube on all of the moving parts. Your latch may need to be adjusted. If it looks like this one:
https://www.etrailer.com/question-134607.html
I don't recall exactly but I think I raised up the sliding panel all the way, pulled in the catches, lowered one side and turned/twisted it to get it out completely. There should be two hidden pins at the bottom of the sliding panel that hold the panel in the grooves.
Kind of like this, yours...
Although rare, you could have a wire that can't handle the load of the circuit, as in a wire that has rubbed or been flexed enough to break some of the strands, or a corroded connection somewhere in the circuit.
Are you testing the input voltage (to the light fixture) with a load on it? If...
Perhaps unrelated, but I would question the use of a 1A fuse in the #2 DC circuit. What does that circuit feed? Typically circuits 1, 2 & 3 are all 15A fuses, if I recall correctly. Your camper's manual may or may not detail the fuse sizes.
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Is there a weight sticker on the driver's side (left) panel, near the front of the camper, that shows the weight values? If so, that may have a clue as to what model number it is and the date of mfr. My former Coleman's looked like this:
I used white lithium grease on my Coleman Cheyenne's slipper springs, where they "slip" on the frame. You will probably want to figure out what's squeaking first.
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Keep in mind that some vehicles have separate fuses for the trailer connections. My Tahoe even has individual fuses for the trailer turn signals -- one for the right, and one for the left, independent from the truck's turn signal circuits. So even though the TV lights work, the trailer ones...
How to measure hitch height:
https://www.etrailer.com/faq-ballmount.aspx
It seems to me that the standard height of a trailer, if there is one, is around 17". However, trailers can have their own unique hitch heights, so best to use the link above to determine ballpark rise/drop, and adjust...