This guide is the map behind many RV electrical problems. Before replacing parts, identify which energy system the failed load uses.
120V AC loads
Household-style outlets, microwave, rooftop A/C, electric water-heater element and many converters use 120V AC from shore power, generator or inverter.
12V DC loads
Lights, water pump, furnace blower and controls, refrigerator controls, detectors, slides and many appliance boards use 12V DC from batteries and converter output.
Converter versus inverter
A converter turns AC into DC and charges batteries. An inverter turns battery DC into AC for selected outlets. Inverter/chargers can do both.
Protection devices
AC uses breakers and GFCI protection. DC uses blade fuses plus larger fuses or breakers near batteries and high-current devices. Repeated trips mean a fault, not a nuisance.
How to use the map
- Name the failed load.
- Identify whether it needs AC, DC or both.
- Confirm the source.
- Check protection.
- Inspect wiring and device last.
Keep troubleshooting
Use these related RV Solver resources to narrow the problem and avoid parts guessing.
When to call a professional
Use qualified help for live AC testing, transfer switches, burned wiring, inverter/charger installation or unclear electrical modifications.
Sources and editorial notes
RV Solver pages are written for practical owner education, then safety-edited for common electrical, propane, water, roof, appliance and towing risk points. Always confirm procedures with the manual for your exact RV and installed component. See our editorial policy.