Scary. Right after I bought my motorhome I discovered some idiotic wiring by our buddies at Airstream (at least, I assume that's who did it - it was on some fog lights that were normally installed by Airstream). Briefly, the switch for the fogs was illuminated, and the fuse for the fog lights was electrically after the switch...so when the switch broke and shorted out, it connected the coach battery to ground, through an unfused 16 gauge wire. I discovered this by noticing the wire was very warm. Bad wiring in a vehicle MEANT to be slept in? I've been on the lookout for similar idiocy ever since.
1995 Airstream Classic 30' Excella 1000
2014 Ram 2500 Crew Cab with Cummins 6.7L Diesel
Sold but not forgotten: 1991 Airstream B190
Sold: 2006 F-250 6.0L Powerstroke Supercab