RV outlets not working on shore power: GFCI, breakers and pedestal checks

Understanding RV 120V power

Your RV's 120V system runs the outlets, microwave, air conditioner, fridge (electric mode), water heater element and the converter that charges your battery. It's fed by a shore power cord (typically 30A or 50A) or a generator, usually through an automatic transfer switch that picks between them.

Danger: 120V and 240V can kill. Never open the main distribution panel, transfer switch or pedestal unless you are qualified. Don't work on wiring in wet conditions. If a pedestal is damaged, sparking or hot, don't plug in. Report it to the campground. Everything in this guide can be done without opening live panels.

Step 1: Is it just one outlet or everything?

• One or a few outlets dead: almost always a tripped GFCI or a tripped branch breaker.
• Everything 120V dead (but 12V lights work on battery): the problem is the supply: pedestal, cord, surge protector, transfer switch or main breaker.
• Some 120V things work, others don't, on a 50A rig: one "leg" of the 50A supply may be missing (pedestal breaker, cord or adapter problem).

Step 2: Check the pedestal

1. Turn the pedestal breaker off before plugging in or unplugging. This protects the contacts from arcing.
2. Plug in fully, then turn the breaker on.
3. Test the pedestal outlet with a plug-in outlet tester (on the 15/20A outlet) or check the readout on your surge protector. Many campgrounds have weak or miswired pedestals.
4. Try resetting the pedestal breaker. Breakers in old pedestals sometimes need a firm off-then-on.
5. If you're at home on a household outlet using an adapter, remember a 15A outlet can't run an air conditioner and much else at the same time.

Step 3: Check your surge protector or EMS

A surge protector or EMS is great protection, but it's also a common point of "failure". Many EMS units delay power for a couple of minutes on start-up, and cut power if voltage is too high or low, or if they detect wiring faults. Check the display or indicator lights. Error codes are listed in its manual. If you suspect it's the problem, test by plugging the RV directly in briefly, but only after confirming the pedestal is wired correctly.

Step 4: Inspect the cord and adapters

Look at the shore cord plug and the RV inlet for burned, discoloured or melted pins. That's a sign of a loose or overloaded connection, and it's a fire risk. Replace damaged plugs or cords. Don't keep using them. Check dogbone adapters too.

Step 5: Find and reset the GFCI outlets

A ground-fault circuit interrupter (GFCI) cuts power when it detects current leaking to ground, which protects you from shock. In RVs, one GFCI outlet often protects several other outlets: maybe the bathroom, kitchen, outdoor outlet and even the outlet the converter or fridge plugs into.

1. Find every GFCI outlet (they have "Test" and "Reset" buttons). Common spots: bathroom, kitchen backsplash, outside, and sometimes inside a cabinet.
2. Press Reset firmly on each one.
3. If a GFCI won't reset or trips immediately, unplug everything from the outlets it protects and try again. Plug items back in one at a time to find the culprit.
4. An outdoor outlet that's damp from rain, or with a cord plugged into it in the rain, is a frequent cause of tripping. Let it dry out.

GFCIs wear out. If one won't reset even with nothing connected, it may need replacing. That's a job for someone comfortable with 120V wiring.

Step 6: Check the breakers

In the main panel (usually behind a cover plate):

1. Look for any breaker that's in the middle or "off" position.
2. Reset by pushing it fully off, then on.
3. If a breaker trips again immediately, don't keep resetting it. Something on that circuit is shorted or overloaded.

Overload math: A 30A RV can run roughly 3,600 watts in total. A rooftop A/C, microwave and electric water heater together can exceed that. Turn off the water heater element or the A/C while microwaving.

Step 7: Generator works but shore power doesn't (or vice versa)

That pattern points to the automatic transfer switch, which has contacts that can burn or stick. You may hear a "clunk" a short time after the generator starts. That's the switch changing over. Transfer switch diagnosis involves live 120V and is best left to a technician.

Step 8: Only the fridge or water heater has no electric power

The fridge and water heater often have their own breakers and sometimes plug into an outlet behind an access panel. Check both. Also check that the electric mode is actually switched on. The water heater element switch is often in an odd location such as near the floor, in a cabinet, or on the monitor panel.

Testing an outlet yourself

A plug-in outlet tester is the safest way to check an outlet. If you use a multimeter, set it to AC volts, keep fingers behind the probe guards, and expect roughly 110 to 125V between hot and neutral. If you're not confident with live measurements, skip it and use the plug-in tester.

Hot-weather and cold-weather notes

• In summer, A/C start-up draws a big current surge. At weak pedestals, voltage can drop low enough for an EMS to cut power. Running fewer loads helps.
• In winter, electric space heaters are a common overload, especially on 15A household outlets with long extension cords. Use a properly rated, short, heavy-gauge cord and never run cords under rugs.

When to call a pro

Call a licensed electrician or certified RV technician if a breaker trips repeatedly, you smell burning or see scorched wiring, outlets feel warm, the transfer switch misbehaves, or if your outlet tester shows reversed polarity or open ground in the RV itself (not the pedestal). Don't use the RV on that power until it's fixed. An open ground can make the RV's metal skin live, often called a "hot skin" condition.