Understanding the Fuse Panel of an RV Distribution Panel If it is not lighting up, it is a bad fuse. Newer RV distribution panel models will have lights underneath the fuses and if the light is on, it is indicating the fuse has gone bad. When working with an RV distribution panel make sure that all power coming into the panel is 12V RV Fuse Box - Vintage Trailer Supply This is the highest quality stand-alone RV fuse box we've ever seen. It is a surface-mount box that allows for wiring up to 9 independently fused DC circuits. It's ideal for replacing a converter that contains an internal fuse panel (like older Univolts) with a converter/charger that does not (like modern Inteli-Power Converters).