Hey everyone, just pulled my Class A out of storage and we're having our first electrical nightmare. Everything was working perfectly when we left for town this morning - A/C running, fridge humming along on shore power, all the usual stuff. Came back from dinner and it's like someone flipped a master switch. Zero power to any 120V outlets, A/C is off, and the fridge automatically switched over to propane mode. The weird part is our surge protector shows everything's normal and feeding power just fine. I checked the main panel and I'm getting 120V readings between hot-to-ground and neutral-to-ground like it should be. None of the breakers tripped either. There's a GFCI outlet in the bathroom that won't reset - the button just pops back out and doesn't make that normal click sound. Tried switching to our Onan generator thinking it might be a shore power issue, but same exact problem. Our setup doesn't have a transfer switch, just plugs the shore cord into a 30-amp gen outlet. Could that bathroom GFCI really kill power to the entire rig even though we have separate breakers for different zones?
A faulty GFCI outlet can indeed cause complete loss of 120V power to an entire RV even when voltage is present at the panel. The bathroom GFCI that won't reset is likely your culprit, as many RVs wire all outlets downstream from the main GFCI for code compliance.
This is one of those frustrating electrical gremlins that makes perfect sense once you understand how RV electrical systems are wired. You're absolutely right to suspect that bathroom GFCI - it's almost certainly the source of your troubles. Many RV manufacturers wire their 120V outlet circuits to run downstream from a single GFCI outlet, typically located in the bathroom. This setup meets electrical code requirements while keeping costs down, but it creates exactly the scenario you're experiencing.
When that GFCI fails internally, it cuts power to everything downstream, even though your main panel shows proper voltage and none of the individual circuit breakers have tripped. Think of it like a traffic light that's stuck on red - cars can line up behind it all day, but nothing gets through until that light starts working again.
The fact that you're seeing identical symptoms on generator power confirms this theory. Since your shore cord plugs directly into the generator outlet without a transfer switch, the power still flows through the same GFCI-protected circuits. A failed GFCI will block power regardless of the source - shore power, generator, or even an inverter.
That reset button behavior you described is a classic sign of GFCI failure. When the internal mechanism fails, the button loses its ability to latch in the reset position and won't make that distinctive click sound. You might also notice the GFCI feels loose or wobbly compared to when it was working properly.
Before replacing anything, I'd recommend using your multimeter to test for voltage at the GFCI outlet itself. You should see 120V on the line side (power coming in) but zero volts on the load side (power going out to other outlets). This confirms the GFCI is receiving power but not passing it through.
Replacing an RV GFCI outlet isn't complicated, but you'll want to work safely. Start by disconnecting shore power, shutting off the main breaker, and verifying power is off with your multimeter. Most RV GFCIs are standard residential units, but verify the amperage rating for your specific unit - typically 15 or 20 amps.
When you remove the old GFCI, you'll likely find two sets of wires: line wires (bringing power in) and load wires (sending power out to other outlets). The line wires connect to terminals marked "LINE" and the load wires connect to "LOAD" terminals. Getting these backwards will prevent the GFCI from working properly.
Take a photo of the wiring before disconnecting anything - it'll save you headaches during reinstallation. Wire nuts in RVs can work loose over time due to vibration, so this is also a good opportunity to inspect all connections and ensure they're tight.
Once you've installed the new GFCI, turn the main breaker back on and test the reset function before checking your other outlets. The button should click firmly into place and stay there. Then systematically test outlets throughout the RV to confirm power has been restored.
This is also a good time to test all your GFCI outlets with a proper GFCI tester or by using the test and reset buttons monthly. Many RV electrical issues stem from failed GFCIs that owners don't realize have stopped working.
For a comprehensive understanding of how your RV's electrical system works, including the relationship between different components, it's worth familiarizing yourself with the basics. Electrical problems like this become much easier to diagnose when you understand the big picture.
GFCI outlets in RVs work harder than their residential counterparts due to constant vibration and temperature fluctuations. Testing them monthly and replacing them proactively every few years (or as recommended by manufacturer) can prevent situations like this. Consider upgrading to weather-resistant GFCIs designed for harsh environments - they typically last longer in RV applications.
Keep a spare GFCI outlet in your parts kit along with basic electrical tools. This type of failure always seems to happen at the worst possible moment, usually when you're far from hardware stores or on a weekend.
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