It’s not uncommon for your RV’s outlets to lose power, in fact it happens quite often. Generally, this type of failure is caused by your motorhome being in motion while you are driving, and it usually means that it is a loose connection on the outlet or, less commonly, on the supply line of the power cord.
Isolate the problem
The first thing you should do is isolate the problem. For example, are all the outlets without power or just one or two on the same wall? If all the outlets in your RV are without power, you probably have what is called a “global failure.” By this I mean that if all 110/120 volt outlets in your motorhome are without power, the problem is most likely in the shore power supply or somewhere in the junction box that supplies the load to those outlets.
On the other hand, if you find that only a few outlets or light fixtures are without power, the problem is most likely in the load line that is passed from the outlet or light fixture to the next outlet or light fixture. In short, this is where you need to become a detective.
What does “ganged” mean?
110/20 volt outlets have four terminals or screws to secure the electrical cord into the outlet. If you only have one outlet on the power line, you only need two of these connectors or screws. However, if you have multiple outlets on a load line, you use the other two connectors to run the load to the next outlet. This is called ganging.
With a 12-volt power line, the load is supplied with direct current, and any break in the line will cause that line to lose its continuity because the load must be returned to the power source.
This is not the case with 110/120 volt power, which uses alternating current, so the load is returned to the power source through the same line it was fed through. If you have ever been electrocuted with 110/120 volts, you may have noticed that it feels like a buzz. This is because the current is bouncing back and forth between you and the power source.
So, a single outlet in a series circuit may not work while all the other outlets continue to work normally.
Here is how to check your outlets
The best way to check an outlet if you suspect it’s not working properly is to use a multimeter. To do this, set the multimeter to the setting with a single “V,” as this is the setting used to test a 110/120 volt power load. When the multimeter is set to this setting, it will usually read 00.12 or a similar small number. Do not worry about these numbers because they are just stray voltages that are in the air, and it is normal to see these numbers. Now you can test the outlet.
Your multimeter comes with two cables. One black and one red cable are plugged into the openings of your electrical outlet to test for continuity. If you have ever noticed, most plugs have one side wider than the other, as does the socket. The wider slot is for power and the smaller slot is the neutral.
Unlike DC, where the red wire is the power supply and the black wire is the ground wire, in AC, these wires are black, white, and a bare copper wire. The black wire is for power, the white wire is the neutral, and the bare copper wire is the ground. To test your outlet, plug the black lead of your multimeter into the wider slot. Then plug the red lead into the other slot. Your meter should now read 120, which means that part of the outlet has power. Repeat this process for the other slots of the outlet. If the meter also reads 120, that outlet is powered.
It’s not uncommon for things to come loose in an RV while traveling, and your outlets are no exception. If the outlet is not receiving power, turn off the breaker for that load line and check the outlet. Are all the wires in place? If not, this may be the cause of the power outage and you can simply reconnect the wire to the correct outlet and you should be back up and running. If you have GFCI outlets (GFCI stands for Ground Fault Circuit Interrupter), also check to see if they have tripped. If so, you should simply press the reset button on your GFCI outlet.
As I have said in several other articles where I give you advice on electrical issues, if you are not comfortable working with electricity, you should hire a qualified professional to do this type of work.