Steve Savage submitted this article to RVtravel.com when he was a Master Certified RV Technician with Mobility RV Service.
On close to a third of our service calls we find nothing wrong with the RV. The problem is not so much the RV as it is the owner who has either forgotten how to operate something or simply forgotten to turn something on. For electrical problems, here’s one simple check you can make that can save you a costly (and needless) service call.
If you find your interior lights, refrigerator, water heater and the furnace aren’t working and you’re not connected to shore power, think battery. The loss of “house” battery power will generally kill all of these systems. All appliances that have computer boards require 12-volt power that comes either from your batteries or the power converter in your RV.
Look around if there’s an electrical problem
You’ll always find a fuse located within 18 inches of your batteries. This is an industry code, so all manufacturers do it. An RV’s power converter is fused to protect it in the event your batteries are hooked up incorrectly. Check the fuse first. If it’s blown, try replacing it.
Check your RV house batteries, too. If they’re dead, you can “work around” the problem by hooking up a battery charger to them. If you need to charge your batteries and your power converter has died, you can always hook a battery charger to your batteries. Batteries do not care where the power to charge them comes from.
Save your money, and save your technician from having to making an unnecessary call.