I also had fat fingers when I was working on my class c. If your radio was wired were the use , store switch killed it then it's wired to the coach batteries. The ignition lead is a fuse in the coach fuse panel. Should be labeled. The keep alive wire on mine was wired to the battery side of the use,store relay via a inline fuse. That relay was mounted behind the coach fuse panel.
I had no help from Thor tech support. So hours were spent tracing. Which I found five other unlabeled in line fuse holders!
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