Smart Glow Fuses
Smart glow fuses remove the need for a test light or meter. Smart glow fuses have a built-in LED light that light up when the fuse is burnt out. Smart glow fuses are easily visible — day or night. When you open the fuse panel there is no more searching to figure out which fuse protects a particular accessory. The guilty fuse will be glowing brightly so you can go right to the source of the problem.
However, it is critical that the prudent RV owner understands that if you are not 100% confident in what you are doing, leave electrical issues to the professionals. Besides injury or death, you could easily destroy thousands of dollars in RV electrical gear by doing something wrong. However, 12-volt DC automotive circuitry is unlikely to give you a shock vs 120vac circuitry.