RVs combine a household-style 120 V AC system with a car-style 12 V DC system. Appliances like the air conditioner and microwave use AC; lights, the water pump and the furnace blower use DC. The first job is to work out which side has lost power.
⚠️ Safety First
- Turn off breakers and disconnect shore power before opening any panel or touching AC wiring.
- Never defeat a ground pin or use a damaged cord. Replace burned or melted plugs and receptacles.
- Treat any burning smell, buzzing breaker or warm cord end as urgent and stop using that circuit.
🧰 Tools & Materials
- Multimeter (AC/DC voltage, continuity)
- Plug-in receptacle tester
- Flashlight
- Spare fuses and a fuse puller
- Surge protector or electrical management system
📋 Step by Step
1 Check the source
Start where the power comes in.
- Test the campground pedestal with a receptacle tester before you plug in.
- Match the adapter to your RV’s amp rating. A 15 A outlet limits you to roughly 1,800 W, which can’t run an air conditioner and a heater together.
- Seat the cord fully and look for scorching, melted plastic or loose pins at both ends.
2 Reset the AC side
Several outlets often depend on one upstream device.
- Press the GFCI outlet’s reset button — it commonly protects the bathroom, kitchen and exterior outlets.
- Reset the main and branch breakers in your RV’s panel.
- If a breaker keeps tripping, unplug everything on that circuit and test again, then reconnect items one at a time.
3 Check the 12 V side
A weak battery causes odd, intermittent faults.
- Measure the house battery at rest: about 12.6 V or more for a fully charged lead-acid battery.
- With shore power on, the converter or charger should lift the reading to roughly 13–14.5 V.
- Check fuses for the failed circuit, using your RV’s fuse chart.
4 Look for loose or corroded connections
Voltage drops hide in dirty connections.
- Clean and tighten battery terminals and ground straps.
- Check connections at the converter, the disconnect switch and the chassis ground.
5 Hunt for a parasitic drain
Batteries that go flat in storage are often being drained slowly.
- Switch off the battery disconnect when storing the RV.
- To measure the draw, connect a multimeter in current mode in series with the battery cable and watch the reading; then pull fuses one at a time to find the load.
- Common culprits are detectors, stereo memory and control panels left on.
🔧 When to Call a Professional
Stop and book a qualified technician if you see any of these:
- Burn marks or a hot smell at the panel, plugs or outlets
- Repeated breaker trips with nothing plugged in
- Inverter, transfer switch or shore-cord replacement
- Any work inside the AC distribution panel if you’re not experienced
❄️ Electrical in the cold
Batteries lose capacity in cold weather and a discharged lead-acid battery can freeze. Electric heaters can overload a 15 A supply — spread loads between circuits and watch the breakers. Some winter campgrounds supply limited power, so check the amperage before you book.
🔎 Electrical Symptoms and Next Steps
| What you notice | Likely explanation | Safer next step |
|---|---|---|
| All AC outlets dead | Shore supply, main breaker, transfer or inverter fault | Verify supply status and call technician |
| One bathroom/kitchen outlet dead | Tripped GFCI or branch issue | Follow manual reset once; investigate recurrence |
| 12V lights dim | Low battery or charging problem | Reduce loads and check monitor |
| Breaker repeatedly trips | Overload or electrical fault | Stop resetting and seek inspection |
🍁 Checks specific to campgrounds
Before blaming your RV, test the campground pedestal outlet and breaker and reset it if safe. Cold weather can reveal weak batteries or loose connections, so check battery voltage and look for tripped GFCI outlets.
📚 More Guides on This Topic
- No power: 12V and shore-power checks – a symptom-by-symptom diagnosis with a decision diagram
- How RV 12V and 120V systems work – background for diagnosis
- 30-amp vs 50-amp service – adapters and campground limits
- Connecting shore power safely – hookup steps