Well, it being the day before the 4th, I ducked out of the lab early today and came home to check on those items y'all had mentioned earlier before I headed up to Home Depot for a voltmeter and anything else I might need.
I should start by saying before I left it last evening, I turned off all the lights, AC, TV, water heater (it was on propane to test it anyway), and left the fridge on AC power, shut and locked the door and deadbolt and used the little holder tab for the upper half of the door. It was still plugged in to shore power and still had garden hose water turned on.
Before I even unlocked it this afternoon, I walked around to look for things that might be causing a short or grounding issue. I opened up the top and bottom access panels behind the fridge and checked that those connections looked good and felt tight (they did) and then took a peek at the large wiring around the torsion bar/roof support. It looked like some of the unbundled wires at the bottom were touching the arm slightly, so I moved them out of the way, just to be sure. Their individual wire sheathing was intact and looked alright, but I figured the less things they touched, the better.
Next, I opened up the camper and the first thing I did was test one of the front half ceiling lights and lo and behold, it worked! Just as bright as normal! I tried the rest and they were good too. I figured I'd see if I could go 2 for 2 and tested the radio. The speakers still weren't working, but I was able to see if they were faded to the rear (they weren't) and at that point, figured I'd remove them to see how they're connected. Y'all were 100% right, they're attached by normal speaker wire and all of the electrical wire I was seeing behind it was just where it happened to be for the other lighting. The connections on the speakers were tight, so next I used a little 'el cheapo' continuity tester (the kind that just beeps when you've got some juice, no volt readings or anything) and one speaker beeped slightly and the other didn't. So, I think somewhere the speaker connection is shot.
Now, I figured I'd double-check the battery just for good measure and Bill was right, the fuse is on the red wire leading away from one of the battery terminals and NOT between the two. Everything else looks like the diagram Bill attached, except mine also has another wire leading from that same terminal as the lead with the fuse that is labeled "PowerJack +", so I'm assuming that's for the electric jack up front.
So, I'm thinking most likely, there was a grounding issue when those wires from the TM going up touched the arm. Alternatively, I did notice after the AC was running for a bit, water was dripping down that area as well and it reminded me, I did rain yesterday too..I may not know much about electricity, but I do know it doesn't play well with water! After giving it time to dry out, perhaps that may have been the solution. Either way, we'll get more rain in the next few days I'm sure, so I'll be able to test that theory and I'll also be thinking of a better way to keep those wires off of the metal arm...perhaps electrical tape bundling them together and then using a zip tie to attach them to another cable?
Thanks Fourteener, Dave, and Bill!
I'm sure I'll have more questions and the next time I head up to Home Depot, I'll grab a cheap volt meter with some numbers so I'll be able to do a bit more trouble-shooting on my own and have more info when I post in the future. Y'all are awesome and Happy 4th of July!
-Dan