Don is a retired engineer and long-time motorhome owner who enjoys helping readers deal with the increasingly complex technology of RVs.
Electrical Problems in RVs: For the Novice
Electrical problems in an RV or camper are very common, and often RV owners don’t know where to start when they deal with them.
This article provides some basic information for the RV owner to help diagnose and repair electrical problems efficiently and safely. I'd like you to:
- understand your RV electrical system in general, and
- learn how to do some very basic troubleshooting on your RV.
First: Know the Difference Between a Major and a Minor Electrical Problem
If you own or rent an RV, you will want to know enough to at least make a walk-around inspection before you go on the road, especially of the electrical system. Even a novice can learn how to inspect for problems, and determine if the problem is major or minor.
A major problem, for example, may be present when a refrigerator stops working, and you wonder if you should look into the wiring and propane-management circuitry on the back of the fridge or not. For the electrical novice, the answer is no; stay away from such repairs yourself. They are too dangerous, especially when they involve AC power or propane. You should always contact a qualified service tech for resolving such problems.
But a minor problem, one you could address on your own, could be something as simple as re-setting a breaker or GFI that has "kicked out," replacing a blown fuse that is easily accessible, taking an educated guess as to what caused the breaker or fuse to shut off, or checking the water in your battery.
So how do you tell? Before you start with any hands-on troubleshooting, keep in mind that safety comes first.
Electricity Can Kill!
Please remember this when using the information below!
Before you start opening panels and messing around with electrical systems, in an RV or camper or at home, observe these warnings.
WARNING 1: If you do not know what you are doing, do not touch anything, and call your RV manufacturer, or RV Roadside Assistance company, or if at home, your local certified electrician. Remember, again, ELECTRICITY CAN KILL!
WARNING 2: If replacing a blown fuse or resetting a kicked breaker doesn’t fix the problem, you should seriously consider backing off and calling your RV manufacturer's Service Center for advice before doing anything else.
Now—with these warnings in mind—here are some minor problems that you may be able to fix, and some diagnostics that you can run yourself.
Troubleshooting Your RV's Electrical Problems
Every problem is different, but before or after you read the discussion just below of the basics of your system, check the four sections further below on troubleshooting common problems:
- Fuses and breakers
- The 12-volt system
- The power source
- Appliance current draws
Read More from AxleAddict
Plus I include a section on terms and abbreviations that you may run across while doing your electrical investigation.
Some Basic Electrical Information for the RV Owner
A modern RV contains a lot of built-in electrical devices. And along with these devices comes complicated electrical control and protection circuitry designed to protect the RV and its occupants.
Starting with the absolute basics, your RV's appliances can be powered in three different ways. Appliances may use any of these three power sources, individually or in combination.
- The AC (alternating current) electrical system (generally 115 volts), which runs the air conditioner and some other devices.
- The DC (direct current) system (12 volts), which runs the lights, switches, slides, and thermostats.
- In addition, refrigerators and some appliances run on propane fuel.
AC power comes into the RV from your generator, or from the campground or other outlet you plug it into: a 20-amp, 30-amp, or 50-amp supply. The AC power control panel distributes this power to the appliances and outlets that use AC power, for example the air conditioner. The campground supplies AC power on two different wires: a 240-volt supply is split into two "legs" of 115 volts or so.
Your DC power comes from a battery or batteries (like in the picture above). Whenever the power stored in the batteries gets low, the converter charges it up. The converter uses the higher-voltage AC power that comes in from the campground or generator through the 115-volt AC breaker panel and converts it to 12-volt DC.
The converter that charges your 12-volt batteries is often called an "inverter." "Inverter" is actually the name for another device most RVs have that changes 12-volt DC power to 115-volt AC for use in televisions and such.
The 12-volt output of your converter likely goes through two 30-amp fuses that feed your 12-volt fuse panel. The 12-volt DC power goes to the lights, switches, and slides, and to the controls of many appliances including the heater/air conditioner and refrigerator.
Both electrical systems can develop weakness in many places, especially when being hauled around on trips. Any RV or towed vehicle vibrates in transit. And these vibrations will, at times, shake electrical connections loose, in addition to the wear and tear that wires and appliances go through in normal use. If a wire has its insulation rubbed off, or something inside an appliance shakes loose or burns out, then current can stop flowing in your 12-volt or 115-volt system. Or it can flow into a place where it is not supposed to flow, causing a “short,” and this excessive flow of current can burn out wires and appliances, or in the worst case cause a fire or injury.
Because of these risks, the RV will have breakers or fuses to shut off power if anything goes wrong:
- a set of AC fuses or breakers to interrupt the 115-volt AC power coming from outside the RV if anything goes wrong in the 115-volt system.
- a set of DC fuses or breakers to interrupt the DC power if anything goes wrong in the 12-volt system,
- and also, in many 110-volt receptacles, mini-breakers called GFIs or GFCBs (Ground Fault Indicators or Ground Fault Circuit Breakers), which shut off power to appliances if a wire or circuit is creating a short.
1. Troubleshooting Fuses and Breakers
Troubleshooting often begins, and may well end, with resetting a breaker, replacing a fuse, or resetting a Ground Fault Indicator, and then seeing what happens. Older RVs tend to have fuses; newer ones, breakers.
The fuses and breakers were placed in the system for two major reasons:
- To protect the RV and you the owner from harm if an appliance or other electrical device or an electrical line fails and draws too much current.
- To protect your RV and its electrical appliances and other devices if you plug your RV into an electrical service that is not regulated properly and you get electrical voltages that are too low or too high for your RV and its equipment.
So a breaker or fuse going off is often a sign that something else is wrong: a symptom, not a cause of your problem. The problem may be easy to fix or it may not be. Many appliances have sensors on their mechanical parts that will kick a breaker or blow a fuse rather than allow the appliance to continue running in an unsafe mode.
Note that breakers can go bad themselves; if they trip too many times, they can suffer mechanical stress and lose their ability to stay closed at the current they were designed for.
Ground Fault Indicators
A GFI or Ground Fault Indicator (also called GFCB) is a receptacle with a RESET button on it. It is designed, like a regular circuit breaker, to "throw" itself off when the current through it exceeds its designed current limit. Additionally, a GFI will throw itself if even a small amount of current is detected between the "hot" lead and the ground lead of the circuit breaker. These specialty circuit breakers are required in areas such as bathrooms, kitchens, and garages, places where the user of an appliance could possibly be physically touching ground through plumbing, metal, or flooring and using an appliance that is not insulated properly. They are life-savers.
If you find that several AC appliances at once stop working, or if AC appliances quit working but the air conditioner keeps going, suspect a Ground Fault Indicator. If the GFI detects a problem, the GFI-equipped receptacle will shut itself off, often along with several other "slave" receptacles. Push the RESET button and see if that fixes the problem; if not, disconnect all appliances and plug them back in one by one. The problem may be a single faulty appliance or something else entirely. It's possible (though not the most likely thing) that the GFI receptacle itself is bad and needs replacing.
Don't Upgrade Your Fuses
Don’t try to fix your problems by replacing your fuse or breaker with a higher-rated one. Your camper or RV was designed by professionals with your safety in mind, as well as your convenience. Each electrical device was installed on an electrical line that could safely handle the load.
Putting in a higher-rated fuse or breaker does not fix any problems. If you have a blown fuse, replace it with a fuse of the same rating, NEVER a higher-rated fuse. Because:
- You could cause an electrical fire and destroy your RV.
- You could permanently damage the equipment that is supplied by that fuse.
Always remember, the fuse was designed for a normal operational load. And if it blew, something has changed.
With these warnings in mind, below is a table of fuse colors and what ratings they indicate, in case you go shopping for replacement fuses.
Standard automotive fuses are color-coded according to their current rating; below is a short list for your reference.
|Color||Amperage rating (amps)|
2. Troubleshooting 12-Volt System Problems
A bad connection in the 12-volt system can cause failures of various appliances, including slides and lights which run on 12-volt power. A 12-volt problem can cause failure of other appliances and systems if they have 12-volt power to their controls. The refrigerator and air conditioner, even running in propane-fueled mode or on AC power, require DC voltage for their logic circuits, and so may fail to operate when there is a DC system problem. Problems in the DC system can also cause lights or appliances to go on and off.
You can so some simple investigation of the 12-volt system yourself, for example:
- Check whether the fuse or breaker is tripped or not.
- Check whether the fuse is loose.
- Check whether the connections to the fuse or breaker box are loose.
- Check whether the connections to the DC batteries are loose (see initial photo).
- Check whether the batteries have enough water. This is the most common easy-to-fix problem. When your battery is overworked or overheated the water tends to evaporate. Add distilled water only.
- Check whether the batteries are charged enough. A multimeter (see below) should show the voltage between the battery terminals between 13.4 and 14.5 volts DC; if not, the battery may be worn out and need replacement, or it may be low on water, or the converter may not be giving it any power.
- Check whether the connections to the converter are loose.
- Check the fuse on the converter. The converter itself has a fuse or two, often on the front.
If you can find nothing wrong here, you may have a bad converter that needs to be replaced; this is a job for the service center.
Another article of mine has more information about troubleshooting and maintaining your RV's batteries.
Using a Multimeter
A multimeter can measure potential (DC volts, AC volts), electric current (amps), and resistance (ohms).
This device is very useful in the hands of a trained individual, but the novice should not attempt to use all of its functions until they understand what they are trying to measure as well as any dangers involved in making the measurements.
3. Troubleshooting Problems Coming From the Outside Power Supply
The power supply that your parked RV is plugged into can cause problems if it is supplying too much or too little power, fluctuates, is not grounded correctly, or its connector is corroded. Too much current can cause appliances or lights to fail or blow out, and even melt wires or plugs; too little (in an overpopulated campground with an overloaded supply, for example) can cause lamps to dim. Your campground management should be providing safe power at the level they advertise, whether 30 amps or 50 amps; that is their responsibility. You may ask management to investigate, or check with your campground neighbors to see what they are experiencing.
If half your appliances along with your air conditioner are out, one possibility is that half the AC supply from the campground is missing (another possibility is a GFI going off; see part 1 above).
Your on-board or portable generator can also be the cause of problems; it may stop running if your vehicle's gas tank is less than 1/4 full.
Most RVs have a master switch for disconnecting your RV's power during storage. It is a small switch, often near the door on the inside. It will need to be on for you to get power.
Surge Protector, Yes or No?
Everyone in campgrounds seems to be purchasing surge protectors these days. I don't have one. If you buy one, make sure you are purchasing a GOOD one.
Your RV already has surge protection devices: your main AC breaker plus the individual appliance and equipment breakers in your main breaker panel. Like surge protectors, they kick out if the input voltage goes too high.
The only real difference between breakers and a commercial "surge protection" device is that standard breakers are slow to react to voltage changes. A good surge protector should react faster than a breaker to voltage increases and kick out if the voltage exceeds the safe limit of your electrical equipment. Because low input voltages can also harm electrical devices or make them run erratically, most surge protectors will also turn the power off when the voltage is too low.
Now the problem with surge protection devices is that there are no real requirements or specifications for their design. You could purchase one that does not react fast enough to protect your RV equipment. Many of my fellow campers who had surge protectors experienced damage that "fried" their breakers without the surge protector helping at all.
Anyone who buys one of these devices should make sure they get one that has a relatively fast response time, though it's difficult for a camper to tell how fast one surge protector is relative to others.
4. Troubleshooting AC Current Draws
Once again, I recommend that you NOT mess with your RV's 115-volt power system unless you really know what you are doing.
But if your AC breakers or fuses are going off, you can certainly investigate whether your appliances, singly or in combination, are drawing more AC power than you want them to.
Remember that problems with your AC appliances may not come from your 115-volt system at all but from your 12-volt system, because the controls for your fridge and your air conditioner and heater—and other switches here and there—are likely 12-volt.
How Much Current Do Your Appliances Draw?
It's good to know which of your appliances use a lot of current, even when they are working properly. That way you can decide when and where to use your appliances so that the flow of electricity stays within the bounds your system can handle.
The table below lists the approximate MAXIMUM current drawn by common appliances in your RV. Most appliances draw a lot of current during a short period of intense use and less current at other times. These current figures are not exact and vary by manufacturer and model.
Air conditioner (rated 13,500 to 15,000 Btu)
Peak use when starting up
Normal rate after it gets going
Coffee pot (maximum use, while perking coffee)
Once the coffee is brewed, the hot plate under the pot uses much less power, especially if you turn its temperature down.
Less powerful hair dryers might be better for RV use.
Crock pots are useful for cooking in RVs.
Electric frying pan
Hand vacuum (small)
1.5 to 5
Depending on the size, the manufacturer, and the technology.
Water heater (in 120-volt AC mode)
Estimating Maximum Current
If you are unsure what current an appliance draws, use this simple method to calculate the maximum current it will draw when working.
- Look for the appliance's power rating in watts. You may find it on a label on the appliance, or in the owner's manual, or you can contact the manufacturer or look online.
- Divide the number of watts by 120 (the AC voltage), and the result, in amps, is the maximum rating of the appliance for current.
Or you can measure the current an appliance uses with the simple tool below.
Useful Electrical Terms, Abbreviations, and Data
Here is a list of electrical terms and abbreviations, along with a list of color codes for resistors. This information should help the novice be more comfortable with what they are doing when an electrical problem does occur.
Alternating current reverses polarity and flows alternately in both directions in a circuit.
The voltage in your home is AC voltage, in the US typically 115V AC.
The measure of electrical current
An electrical component that stores electrical energy, with a specific storage capacity
A capacitor often has a polarity and must be installed properly. The polarity is generally indicated by a stripe at one end of the part.
A device that opens up or "throws" itself to break a circuit when the current through it exceeds its designed limit. Unlike a fuse, a circuit breaker can be reset when it throws.
Direct current flows constantly in one direction, commonly from a positive lead to a negative lead.
An electrical component that allows current flow in one direction and impedes current flow in the opposite direction.
Current flows from the cathode to the anode. The cathode end is usually marked by a stripe.
A device that is designed to destroy itself or "blow" when the current that passes through it exceeds its designed current limit.
A safety device used to protect electrical devices under adverse conditions. When replacing a fuse, always use one with the same current and voltage rating.
Ground Fault Circuit Breaker
Like a regular circuit breaker, the GFCB "throws" itself off when the current through it exceeds its designed current limit.
Ground Fault Indicator
Same as above
The measure of resistance to current flow.
The resistance can be calculated using the formula: R=V/I, or resistance equals voltage divided by current.
The measure of electrical power.
DC power can be calculated using the formula: W=V x I.
The size of a wire chosen in designing electrical circuits, which determines the current it can handle with minimal resistance.
Standard wire sizes or gauges go from 0 to larger numbers. The larger the gauge number, the smaller the wire size.
One-Letter Electrical Abbreviations
F (upper case)
Farad, the measure of the value of a capacitor. For example, 1 uF means 1 micro-farad.
l (upper case)
Electrical current, measured in amperes. Current can be calculated using the formula I = V/R, that is, current equals voltage divided by resistance.
K (upper case)
One thousand. Example: 1 KW means one kilowatt, one thousand watts.
m (lower case)
One one-thousandth, 0.001. Example: 1 mW means one milliwatt, a thousandth of a watt.
M (upper case)
One million. Example: 1 MW means one megawatt, a million watts.
n (lower case)
One billionth, 0.000000001. Example: 1 nF means one nanofarad, a billionth of a farad.
p (lower case)
One trillionth, 0.000000000001. Example: 1 pF means one picofarad, a trillionth of a farad.
u (lower case)
One millionth, 0.000001. For example: 1 uF means one micro-farad, a millionth of a farad.
V (upper case)
Volt, the measure of electrical potential. Voltage can be calculated using the formula: V = I x R.
W (upper case)
Watt, the measure of electrical power.
Resistor Values and Colors
Gold (as the fourth band)
1% tolerance on the value
Silver (as the fourth band)
5% tolerance on the value
No color (as the fourth band)
10% tolerance on the value
Good Luck Now
The hundreds of comments below have explored just about everything that can go wrong with an RV's electrical system. Add your own questions and comments. But please, again, do not mess with any wiring unless you are sure of what you are doing. Electricity can kill.
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
Questions & Answers
Question: I have a 1999 Trail-lite travel trailer. I am not getting a 12V new battery. None of the lights, monitor panel, pump, Fridge or jack work. No 12v at the power panel. It seems like there is a fuse or open wire in line from the battery to pwr panel. It is the same with or without A/C hooked up, but when it is connected to the A/C, the microwave and the outlets don't work. What do I do?
Answer: First, I assume you have a built-in Converter (charger) that runs on your 110-VAC when hooked up to external power.
If you do then your battery is kept charged by the Converter and all of the equipment you mentioned the run of this battery voltage.
So, you need to check that your battery is being charged by using a multimeter across the battery terminals.
If you read around 14.5 VDC, then the Converter is trying to charge a dead battery. If you read around 13,5-VDC, then the battery is charged, and the Converter is in the trickle charge mode. If you are reading below 13.0-VDC, then the battery is not being charged.
Question: We lost power to our 2015 Thor Hurricane. We have power up to the coach, but only lights working inside. We tried the generator, but still no change. What might cause this?
Answer: First of all, your interior lights are powered by your COACH batteries and that's the reason your lights still work.
Normally, if your exterior power was not working then you could start your generator and it would power everything that used AC-Power inside your RV.
SO, the first thing I would check is the MAIN AC=Power breaker and reset it.
If this isn't the problem then the Power Transfer Switch could be bad, but that's a rare problem for RVs.
Question: So I’m in a hurry to get my Rv cleaned and ready for my return and my little brother somehow managed to hook up the power to 220 instead of 110. Now when it’s hooked up to 110 my multimeter shows power at all of the breakers yet nothing is working. Any tips on starting the troubleshooting? I know the power converter is shot now (I can smell it ) plus was on its last leg anyways any help?
Answer: Well, normally you have 220-Voltage at your input connector from your campsite. BUT, 220-VAC is just two line of 110-VAC that are used in conjunction to provide the 220-VAC for your AC, etcetera.
If your Rig was temporarily wired with one of the 110-VAC lines to one line of your RV and then if your other 110-VAC line was wired to your COMMON line then yes, you will have some of your equipment damaged.
So, first, you need to wire the input power properly with 2 110-VAC lines, Common Line and a Ground line.
Once you get this fixed, then you can check what other equipment in your RV is on the same circuit as your Converter and check that they function or not.
It is not documented with most RV's which 110-VAC circuit powers which equipment, so you could have also damaged such things as your; Hot Water Heater, Fridge, Washer/Dryer, Microwave, and any appliance that was plugged into your receptacles.
Question: I have a LUXE 5th Wheel. 50a. I go plug into the house (with step down to 115), and trip a break-in the house every time. I opened all cat breakers in the camper, and it still trips. I cannot figure this out for the life of me. What is tripping the House breakers, even though all breakers in Camper are open (Off)?
Answer: Your symptoms say that you do not have your RV receptacle at your house wired properly. This is a common occurrence when homeowners try to wire their own receptacles for their RV. If the systems are not compatible, then the house breaker will kick OFF. I suggest that you have an electrician check your wiring out for you before you go any further.
Question: We have a 2012 Lacrosse Travel trailer & we are plugged into electricity, whenever we turn or hot water tank on we use the electric not gas and then if we brew a pot of coffee or use the microwave while the hot water tank is on we always blow the breaker in my friends house , we live in our camper and winter is coming any suggestions?
Answer: You didn't ay, but I am assuming your RV is plugged into a standard 15-Amp or maybe a 20-AMp exterior receptacle at your friend's house.
And, remember, at times, he may be using the same AC-Voltage circuit you are trying to use.
If this is the case, you are just trying to use more current than they have available for you, from their house.
Your electric Hot Water Heater, and then your Coffee Pot and then your Microwave draw the most current of the commonly used appliances in your RV.
If you're going to be there for a year or so, then you should get a standard 30-AMP service wired into your friend's house. Or, learn to use only one of these appliances at a time, every day.
Question: I have a Lacrosse 2016 with 50 amps. My lights are dim, and it looks as if they are going off. It's been suggested that the converter is not passing enough current to the battery. Do you think we need a new converter?
Answer: First, check that you have water in your coach battery. If so, check that it has at least 13.5 VDC across its terminals. This would be the normal voltage reading while a reading of around 14.5 VDC is what you should see when the Converter is charging the battery. I would check these things first before I worried about the Converter; although they do go bad, but not often.
Question: I have a 1974 Fleetwood Southwind RV. My generator doesn't want to start up anymore. What can I do to get it to start?
Answer: The most common reason for a motorhome's generator not starting is a bad fuel filter or fuel pump.
These are usually mounted near and under the generator.
They are cheap and usually easy to replace.
But, remember that the fuel tank in your motorhome is designed with the fuel line for the generator only going down to the 1/4-tank point. This keeps people from "Boondocking" and burning all of their fuel and ten not having enough to get back to civilization. So, make sure you have more than 1/4-tank of fuel for your generator to operate.
Question: I have a 2006 Avenger, and the LED light strip under the awning started flashing and has trouble turning on when it rarely does turn on. Could it be a problem with the wiring or as simple as the led light strip?
Answer: The LED's in these light strips are usually wired so that if one LED goes bad, the others still operate, so that's not our problem.
Also, these light strips are usually wired to operate on your 12-VDC battery.
But, some, in older RV's, are additions that have a box that plugs into 110-VAC and it generates the 12-VDC for the LED's and it also has controls (usually a remote) that allows the LED's to be ON constantly or to Blink. Some even change colors.
I would first trace the LED strip wiring and find where it goes into your RV. The power box is usually on the inside wall, sometimes inside a cabinet.
Question: The battery is charged in my RV but nothing is working, what could be the problem?
Answer: Your symptoms are not very helpful, but if you're talking about your COACH battery, then you should first check that your Cut-Off switch is in the proper position.
Then, use a multimeter and check the voltage across the battery terminals.
If you read around 13.5-VDC then your battery is fully charged, If you read around 14.5-VDC then your battery is being charged, but if you're reading around 12.5-VDC then your battery is not taking a charge and/or your Converter is not trying to charge your battery.
Question: My air conditioner in my RV in the living room stopped working when I went to change bulb over the sink. Do you know how it can be fixed?
Answer: I am afraid you did not give me much information but here goes;
1- Your interior RV lights run on your 120VDC from your COACH battery.
2- Your RV Air Conditioner does not operate on 12-VDC, but on 110-VAC. The temperature control panel in your RV is powered by 120VDC.
The one possibility I can give you from what little you have told me is that your coach battery was not fully charged by your converter, and the addition of the load of that one new lamp was enough to drop the voltage below what is needed by your temperature control panel.
Check your battery for water, and that it is being charged to fix your problem.
Question: I have a 2006 Georgie Boy class A. We camped this weekend with no problems. When we pulled out, I heard an alarm after unplugging. I noticed that the radio wouldn't turn on. Then I saw that the fridge was off, I checked my status panel, water pump, and water heater. All were without power. I fired up the onboard generator, and still no power. Once I got home, I plugged into my 50 amp service, and everything came on fine. Any idea what this could be?
Answer: The RV radio should operate on your engine battery and has nothing to do with the COACH 12-VDC system.
The Water Heater runs on either propane or 110-VAC, and you should have switched over to propane when you unplugged.
The fridge's control circuit board, your water pump, your AC Power Control Panel and your interior lights run on your 12-VDC COACH battery.
As to your generator, when you started it, the power control panel (which operate on your COACh battery.
So, I would get that battery checked for water, and that it takes charge, so that all of those things I mentioned can work properly.
Question: I have a 20ft Jayco Flight and having AC problems. My thermostat is not getting power or else barely measurable. The lights work in the trailer and everything else just the AC/furnace won’t turn on because of the thermostat's lack of power. There is 110 in the control box of the AC, and all fuses in the box are good, and breakers are all on. Could it be the converter is going bad? If not what else could it be?
Answer: Yes, your converter does keep your camper's battery charged, which in turn provides the 12-VDC to your temperature control board.
I would suspect the battery, and then the converter so check that your battery is good!
1: Does it have water in it?
2: Is the converter functioning? Check this by looking for 13-5 to 14.5 volts across your battery terminals. A voltage less than this, even 12-VDC indicates the battery is not being charged.
3: Never trust your campground power! Check that the power at your campsite power box is what it should be.
Question: I have a 1991 Fleetwood Southwind with a Ford 460 LSG875. The alternator has been tested and is good but I am still not getting voltage to the battery. What might be my problem? V8. The alternator is good but still not getting voltage to the battery.
Answer: The output of the Alternator on these FORD truck engine electrical systems goes to the "Fuse and Relay box" under the hood, where it is then distributed to the under-the-hood electrical systems such as the headlights, dash AC, etcetera.
There is also a "fuseable link" (or fuse) that is in line with the main electrical wiring that is there in case there is a short in the RV electrical system for safety purposes.
You should use a multimeter and measure the voltage on the output of the alternator (with the engine running) and then on the large hot wire going into the fuse box.
In each case, you should read approximately 13.5 VDC from that contact to the ground.
If there is no output from the alternator, then it is bad.
If there is no voltage going into the Fuse box then there is a wire which is not connected.
If these are OK then you should go to your engine battery and measure the voltage across the voltage terminals and it should read approximately 13.5-VDC. If you read around 12.5-VDC or lower then there it is not getting voltage from the alternator.
Question: I have a 2012 Fleetwood Bounder. The house batteries were in need of replacement. When the RV was plugged in everything worked. I replaced the house batteries and while replacing them I caused some sparks. I originally replaced with marine batteries for an emergency fix but that didn’t work. I installed correct batteries and now slides, heaters, steps, and tank test meters are not working. I checked the fuse at the battery source and it is good. Any suggestions on what to do next?
Answer: First of all, your steps operate on our engine battery, so that's a different problem if they don't work. Check that your Cut-Off switch is in the right position.
Your Slides, furnace (temperature control panel) and the tank test meters operate using your COACH batteries. Check that this Cut-Off switch is in the right position also.
Considering the sparks you generated, you should check all of the fuses in your 12-VDC Fuse panel for a blown fuse. This should take care of your problem.
Question: What does "high vac" mean?
Answer: Well, your question is very generic, but I can tell you that in the Air Conditioner world HVAC, or "high vac" is an abbreviation for High Volume Air Conditioning.
Question: I have a 96 nomad model 1662. The 12v systems seems split. 1-5 only works when hooked to shore power and other 3 to battery. All lights, fans, and water pump on the 1-5. My question is off shore power... shouldn’t 1-5 switch over battery so you have lights fans and water pump?
Answer: All of your 12-VDC systems operate on your COACH battery.
When you are plugged into Shore power, you have a CONVERTER (charger) that uses the 110-VAC to keep your COACH battery charged.
And all of your 12-VDC equipment should operate regardless of whether you are plugged into Shore power, as long as your battery is fully charged.
Once the battery charge drops below a certain level your 12-VDC equipment can start to function strangely, or not operate at all.
You should check your COACH battery.
Question: I have a 2018 Montana 5th wheel. When plugged into 50amp service, not all my electrical is working. A couple of outlets in the kitchen and master bedroom don't work. My fireplace, microwave and bedroom TV don't work. Everything else is working. I have checked all the breakers and fuses they are fine. What could be wrong?
Answer: First of all, you have several receptacles that are on a GFCI circuit, and there is a MASTER GFCI which has a reset button on it. Make sure this hasn't kicked out.
Second, your Fiver probably has a Cut-Off switch that is used to turn OFF 12-VAC to a number of your interior 12-VDC equipment so that they do not draw current when you put it in storage. This switch can be found somewhere inside your RV, usually near the entrance. Always make sure this is ON/OFF as desired.
Now to your Fireplace, Microwave and BR TV; these all operate on 110-VAC, and I need to as if your Power Control Panel indicates whether you have 50-APM service or not?
Also, I would ask if your AC operates and cools because it runs on your full 220-VAC. If it cools, then you have a problem inside your RV, if it doesn't then you may not have half of your 220-VAC coming into your RV.
Check the items first before you get into anything else.
By the way, your COACH battery is good, right? It has water in it, and it is taking charge, right? You see, a number of your interior control devices use this battery for power such as your temperature control panel, your 2-way Fridge (if you have one) and your CO, Fire and other alarms. This battery is kept charged by your Converter, so make sure it is charging the battery.
Also, some of your appliances, such as your BR TV, Front TV, and possibly the Fireplace may operate using 110-VAC that is generated by an INVERTER which in turn operates off of your battery.
So, keep that battery in good condition and being charged properly.
Question: If my pop-up camper is plugged into shore power but the 12v battery is completely disconnected (I don't have one), will the receptacles still work?
Answer: Your receptacles will have power, but nothing that is powered by your battery will operate obviously. Your interior lights, your 2-way Fridge, your Air Conditioner (temperature control panel is powered by 12-VDC), and other equipment will not operate properly.
The 12-VDC circuits provide a number of conveniences in a camper, even a pop-up.
Question: Where do you find the ground fault breaker in the 2003 W wind trailer?
Answer: The Master GFCI receptacle is typically in the bathroom or in the kitchen of your RV. Simply press the RESET button on it and then check if the Slave receptacles have power to them.
Question: I have a 1999 dutchman camper pull behind. When I plug my 12-volt battery up, the 4 running lights light up, but the one on the back stays off. I know these should only be on when hooked to your vehicle and the parking lights are on. Do you have any ideas on this problem?
Answer: As you probably know, your Dutchman camper battery is only for powering your camper's interior 12-VDC systems and appliances, and should not be wired to your camper's running lights.
Being this old, You should check the following potential problems;
1- The GROUND wire for your battery and the GROUND wire from your tow connector should both be firmly connected to your camper's chassis, and the connections should not be rusty or loose.
2- the HOT wire for your running lights of your camper should be wired to the connections shown on a standard wiring chart for the specific type of connector you are using (4-wire, 5-wire, or 6-wire). Check this article for the proper connector wiring;https://axleaddict.com/rvs/RV-Towing-and-Electrica...
Question: Our electric step doesn't work. Where is the fuse located for it?
Answer: Your information is scarce for me to help you very much but, here goes. Your Electric step runs on your motorhome's engine power, and there is usually a 12-VDC fuse panel inside the RV under the dash somewhere depending on the brand and model.
BUT, you should check a few other things;
1- the steps are activated by a magnetic switch attached to the entrance door, check that the magnet (on the door) and the switch have not been knocked loose.
2- there is a control switch for the electric step usually mounted at the entrance. (read the owner's manual on how it works.)
3- Then you should check that you have power to your step. One indicator that there is power is that the safety light under the top step is operating.
Question: My RV's fridge, hot water heater, and lights won't work. It was a tripped breaker for the hot water heater. Would this be a DC problem?
Answer: The RV lights operate on your 12-VDC Coach battery.
Your Hot Water Heater operates on either Propane or 110-VAC.
Your RV Fridge, if it is one of the standard 2-Way Fridge units will operate on propane or 110-VAC. But the Fridge uses the 12-VDC to power its control panel.
The breaker for your Hot Water Heater is a 110-VAC breaker.
The most likely causes for this breaker to kick out are; 1- you did not have water in the tank, 2- the heating element is bad, or if it resets and there no problem, you had a power surge to your RV.
Question: 2012 Heartland Bighorn 5th wheel. All the outlets in my kitchen stopped working including the microwave also the bathroom outlet, 1 bedroom outlet, outlet for my washer, outside outlets, living room ceiling fan w/light, and the switch that controls the electric water heater. Could we possibly have a bad breaker to keep all these things from working?
Answer: Let's look at your symptome for a moment; 1- your microwave and washer are on regular 110-VAC receptacles. Your bathroom outlets, kitchen outlets, outside outlets and probably that one bedroom outlet are all on your GFCI receptacle(s) anD will need to be reset once you get regular 110-VAC working.
Your ceiling fan is most likely a 12-VDC device and operates on your 12-VDC COACH batteries, which are kept charged by your converter.
So. knowing all of this, I would suspect that the first thing you do be reset all of your breakers in your breaker panel. If this doesn't fix the problem, then you should check that your campsite power box has power.
Question: Where is the RV's converter found?
Answer: Every RV manufacturer places the Converter in a different location.
But, you will generally find it near the COACH batteries. This is because it provides 12-VDC at relatively high current levels and the wires from it to the battery are thicker than many.
I recommend looking at the battery(s) and then tracing the wiring back for several feet and look for connections to the Converter.
Question: All our lights work in our RV, but none of the outlets work. Where do we go for a solution?
Answer: Most of a camper's receptacles get their power from the 110-VAC breaker panel. but there are 2 or more GFCI receptacles that get their power from the MASTER GFCI receptacle.
This receptacle is usually in your bathroom and it has a reset button on it. Check if this button has kicked out and reset it.
Question: The 110V circuits in my RV are not working with either shore or generator power. I’ve reset the breakers and the GFCI. I unplugged it from shore, and with the generator running, I measured 110V across the line and neutral terminals labeled “Primary,” “Aux” and “Load” on the Transfer Relay Delay (TRD). Does 110V on Primary and Aux terminals at the same time indicate a faulty TRD? With 110V on the “Load,” but no power at the receptacles, where does my problem lie?
Answer: If you have your shore power unplugged, then there should only be power on the aux terminals, and with the generator off and plugged into shore power, only the primary terminals should have power.
Question: I have no power on my front jacks, they only work when the truck is running. What should I do?
Answer: Not very much information on your camper, but let me try to help.
First of all, with most Fivers and camper trailers with power jacks, the jacks are powered by the camper's battery.
With that said, there are also campers that utilize the towing vehicle's battery via the towing cable for the jacks.
With what you have described, I assume your jacks are powered by your towing vehicle.
Question: I have a 1998 Itasca MH. One of the 110V circuits ( 5 receptacles) went out suddenly when we were parked. The circuit breaker was not tripped. I checked, and it is working. Is there something I can check to locate the problem?
Answer: Are these receptacles part of your GFI circuit? Check that the main GFI receptacle has not kicked out.
Question: Why does the microwave in my RV keep shutting off about every two minutes?
Answer: First, are any other 110-VAC appliances having problems? If not you should focus on the microwave, but if other appliances also have problems, then you should check out your 110-VAC power source, which I assume is a campsite power box. Have the campground maintenance people check out their power system at your campsite.
On the other hand, if the problem is only with your microwave, then you should, first of all, make sure that you do not have too many appliances running and limiting the source power of your RV equipment.
Question: I have one car & 2 trailers. A boat trailer & a utility trailer. When I plug the car into the boat trailer, everything works as it should. When I plug the same car into the utility trailer, the marker light come on & the left brake & signal light work, but not the right brake or signal light. The bulb is good. What else can it be?
Answer: Trailers, especially boat trailers are famous for developing bad ground connections to the chassis. Check the wiring and if the ground connections to the chassis are oxidized and need cleaning.
Question: I blew a fuse in my 12v camper trailer by touching pos to neg. Now my lights don't work. I replaced the fuse, and the bulbs work. Tested for power( I have it). But when the bulb is in, suddenly there's no power?
Answer: You may have melted one of the wires to the lamp fixture.
Either the Hot or Common wire could be bad. You will need to trace the wiring to find where it may be bad.
Question: When plugged into a 30 amp pedestal and running one ac, my surge protector meter will indicate 22 amps on leg 1 and 2 amps on leg 2 then for no apparent reason leg 2 will shoot up to 16 amps and trip the breaker. Then happens minutes after resetting the breaker or sometimes hours later. This is on a 2015 Tiffin Allegro Red. Why would my RV trip its breaker frequently?
Answer: First of all, your Allegro has a 50-Amp service input. SO, if you're plugged into a 30-Amp campsite power box then you are using a 50-to-30-Amp adapter. Hopefully, you are using a standard adapter and not something homemade for this.
With this said, your current indicates that your RV has something else running because your Air Conditioner unit only pulls 5-8 Amps when running and maybe up to 12-AMPS when it is starting up. SO, I recommend that you turn OFF whatever else you have running (on 110-VAC) that is drawing so much current. Remember, 30-Amps means 30-Amps, and that's all you have available at the campsite, MAXIMUM!
It is common for people with a rig that runs on 50-AMP Service having to ration their use of power when they have to use a 30-Amp service, but regardless, your meter on your Surge Protector should not be indicating such high current readings normally.
Question: I have a travel trailer. I took it out on Labor Day. Before leaving, we did our normal prep work: we got the fridge going, and cooled it down for food and such. We have a 30 amp on our trailer and used our normal house GFI outlet and an adapter to hook up the camper. It worked well! But earlier this week, when I plugged the camper in, it tripped the breaker. How do I fix this?
Answer: I had this happen to me once, and it turned out I had oxidation and some char on my power cable contacts. I had to use fine sandpaper to get the contacts cleaned.
Your GFI is not very forgiving when it comes to running a long cable from the receptacle, so make sure your cable and your adapter connections are clean and fit tightly.
Question: I have a 2019 Keystone Passport that I am towing with a 2011 Toyota FJ Cruiser. While I’m towing all my lights and signals work and function properly. When I park and disconnect the power to my trailer it shorts out the fuse in my engine compartment that energizes my Reese Brake controller. If I replace the fuse it’ll work properly until I once again disconnect the trailer. Do you have any idea as to what may be causing my brake controller fuse to short out upon disconnecting?
Answer: Disconnecting the towing power cable should never blow a fuse in your towing vehicle. I suspect that you have a wiring problem where you are putting two power sources onto your Brake Controller, and the fuse blows because of this. Make sure you are not using the DC Voltage line in your tow cable in addition to the possible DC power you have wired to the Brake Controller internal to your towing vehicle (under the dash)?
Question: I have a 93 Bounder and it seems like my system is frying my batteries, it stinks really bad. What would cause my car to stink?
Answer: I assume you're talking about your COACH batteries and not your Engine Battery?
If so, then you need to use a multimeter and check that your CONVERTER is operating properly.
Check at the battery terminals and you should have around 12.5-VDC if the battery is NOT charging, and you should get around 14.5 VDC if the battery is being charged properly, not higher.
Also, before you do anything else check those COACH batteries and make sure they have water in them and that they do not feel HOT! If they're HOT replace them immediately you probably have shorted plates in the battery.
If the charging voltage is very high, as I mentioned, then you need to check out and possibly replace that CONVERTER!
Question: Our outlets are all working but nothing else is working?
Answer: Did you turn your Power Cut-Off switch ON?
Is your motorhome COACH battery fully charged?
Are all of your breakers in your 110-VAC breaker box ON?
Question: I have 2105 Jayco travel trailer. I lost my AC unit, microwave and some outlets tonight. Not sure what to look for. I believe all the circuit breakers are good. Doesn't look like the GFCI in the bathroom is tripped. I do not have a meter to check circuits. what do I check next?
Answer: You should first make sure that you have power at your campsite power box. So, reset the breaker in the campsite power box first.
Then, if you are still without power, check that your exterior power cord is firmly plugged in on both ends.
After this, and by not having a meter, I would contact the campground and ask them to check your power at your campsite power box, and if it's OK then your problem is most likely inside your RV.
Without any more information than you gave me, I would tell you to; 1-reset all of your 110-VAC breakers one at a time and check if anything works, and also make sure your COACH battery has water in it and is fully charged.
Question: What could be the cause of the fuses blowing on the power converter even when it’s not plugged in?
Answer: Without 110-VAC applied to the Power Converter, normally there should not be any electrical problem with the unit.
But, if the Converter has an electrical problem in the output circuitry, then the coach batteries could blow the output fuse.
Otherwise, I would ask if you have had a power surge at your campsite, or possibly even lightning that damaged the Converter.
I would disconnect the batteries from the output, replace the fuses, and then plug the Converter into 110-VAC just to check if the fuses blow without a load.
If they do blow, then you should suspect your batteries or wiring to the batteries.
Your panel shows a House (coach) battery voltage of only 10-VDC. This low voltage means that your batteries are NOT being charged.
Check your converter.
Question: I have lost power to lighting and air in my RV. I have checked everything, but I haven't found anything. The outlets work, though. What should I check now?
Answer: Your symptoms make me think that your 12-VDC battery(s) are not properly charged. In an RV, the interior lights, the temperature control panel, the 2-way fridge control panel, and your alarms all run on your 12-VDC Coach battery. This battery must be kept charged for this equipment to operate properly.
I recommend that you ask yourself:
1- Does your battery have water in it?
2- With a multimeter, can you measure at least 13-5 VDC across the Coach battery?
These are the most probable causes of your problems. Check these before getting into anything else.
Question: The air conditioner in my RV doesn’t work well. My toaster won’t brown the toast, even after seven minutes, and my microwave takes four mins to heat a small coffee. I’m sure the campground circuit is overloaded as I’m not getting the full 30 amps. Everyone in the campground is having the same issues. Is this low amperage damaging my camper?
Answer: If you're not getting 110-VAC to your RV, and when you operate an appliance it loads down the voltage, then you could be damaging your appliances or other electrical equipment.
The campground must provide adequate power to everyone's campsite, or they should tell their campers that they need to leave because their power source is dangerously low.
This is a problem for the campground, and if they don't accept responsibility for any damages, then I wouldn't go there again.
Question: My RV was plugged in, and everything was working, but now the fridge and A/C are not getting electric. I checked all breakers and fuses already. What could it be?
Answer: If your Fridge is a 2-way, then it and your temperature control panel use 12-VDC. So, check your coach battery and make sure it has water in it, and that it is fully charged.
If not, then these appliances will not operate properly.
Question: We have a 2009 Newmar Ventana and nowhere can we find a wiring schematic. The bedroom slide has 3 outlets, 2 on side walls, and 1 under the bed to power an air mattress. All three outlets are dead. I have checked breakers & gfi. How can I further troubleshoot my RV's electrical problem?
Answer: The first thing for you to do is to check if your Power Control panel is displaying that you have 50-Amps service and that all of the green lights are on indicating that your 220-VAC is allocated to everything.
Also, I am assuming that you have no AC power to anything else either.
Question: I have a 2002 Holiday Rambler that lost power to the water heater, washer/dryer, and both AC units. This happened after I disconnected one house battery to check the water level. Do you have any thoughts?
Answer: In case you forgot your 12-VDC powers the temperature control panel which is probably the problem with your AC units. And if your house (coach) batteries are 6-volt and not 12-volt, then you would not have 12-VDC. The water heater runs on 12-VDC, and your washer/dryer runs on 110-VAC, so I can't explain why it doesn't run.
I would first work on getting my 12-VDC system and batteries hooked up properly and the battery converter combination charging the batteries properly. Then I would see what else might not be working.
Question: We purchased a one yr old Mercedes motorhome with 6000 miles on it from an RV dealer. We are on our first trip to Yellowstone from WV and fridge quit. We had it plugged in at home, and the fridge was extremely cold. While driving, it showed it was running on gas, and the light was not flashing, so we assumed it was ok. When we stopped to eat, the temperature inside the fridge was 60. It works when plugged into electric. Any idea of what we can try? It is evening now, and nowhere is open.
Answer: When you are traveling and are not plugged into 110-VAC, your 2-way Fridge will operate on propane, but it must have 12-VDC from your COACH battery, which is charged only when you are plugged into 110-VAC.
So, you should check that COACH battery for adequate water level, and always keep your RV plugged into 110-VAC when you are parked at a campsite. This way the COACH battery will have a full charge and easily keep your Fridge and other 12-VDC accessories running for a full day and night.
I believe this will take care of your problem. When you are traveling, so keep that COACH battery charged before you take off.
Question: As we are driving we have lost all electrical power to all of our lights and gauges. What fuse or relay could be dead?
Answer: Your problem will be in your Chassis electrical system and not your Coach electrical system.
Depending on your RV manufacturer you will have a fuse panel under the dash probably on one of the fenders for easy access. And with some, there will be another fuse panel under the dash.
Question: We have a 1988 Terry Resort. The fridge will turn on when the trailer is plugged into electricity, but we have no outlets, lights or other appliances working. There are no breaker or fuse problems. The fridge starts working when the trailer is plugged in, but nothing else will. Does this sound like a converter issue?
Answer: Actually, NO! Your Converter keeps your battery charged, but your symptoms are that you have no 110-VAC input.
Check your campsite power box and make sure the breakers are turned ON and then check your external power cable connections to make sure they are clean and not oxidized.
If your cable connections are good, then get a multimeter and check if you have power to your Breaker box.
Question: The fridge and A/C in my camper work fine, but not my interior or exterior lights. What could cause that?
Answer: Not very much data to react to, here. IF your RV is a motorhome, your exterior lights operate on your engine battery. But if your Rv is a trailer, they operate on your Coach battery.
So, as you probably know, your interior lights operate on your COACH battery voltage, the same as with your temperature control panel and your Fridge control panel.
First, I would check if my battery(s) is charged and your Converter is operating properly.
If they are OK, then you should check your DC Fuse Panel for a blown fuse.
Question: I have a 40 foot Thor Mandalay, only 20k miles and have had to replace the batteries twice (!) due to the batteries physically sucking in. Do you have any advice please?
Answer: First of all, I have to say that what I have heard from other Thor owners is the fact that they do some strange (non standard?) things with their designs at times.
So, my comments here reflect what I know about the industry electrical systems as a whole.
With that said, I can say that when the walls of an RV battery "sucks in" there has been a serious Short internal to the battery itself. Usually this happens when the plates inside the battery actually touch each other.
This can be caused by having a load on the battery and allowing it to get hot and boil the water out of the battery.
So, considering your symptoms, I recommend that you use a multimeter and measure the voltage across the battery terminals. An RV battery should have a voltage of around 14.5 VDC across the terminals when it is being charged, and not over this number. As the battery takes a charge, this voltage across the terminals will drop to around 13.5-VDC which indicates it is fully charged.
This charging voltage is provided by your built-in CONVERTER. If this charging voltage is suspect, you may have to check out the Converter.
Question: All electrical power (lights and outlets) have stopped working in our slide- out RV. The fuses and breakers have been checked. What would be our next step?
Answer: Check that your converter is fully charging your RV coach battery. If you measure the voltage across the battery and it is LOW (only around 12-5 VDC) then check that the battery has water and is taking charge from your Converter. This could be the problem with your lights.
As to the outlets, first check if they are slave receptacles to your MASTER GFCI and if they are, does your GFCI need resetting? This is a common problem for many RV owners; to forget that their coach battery(s) need to be checked regularly.
Question: 2 out of 6 of my main RV lights are working. They are all on the same light switch, and the bulbs are all working. What could be the problem?
Answer: Which lights? Your interior lights? Your exterior Running lights? We are talking about an RV, Right?
Well, assuming that you're talking about an RV and a series of the interior lights that are wired to a single ON/OFF switch, I would check the following;
1- Your interior lights operate on your 12-VDC from your COACH battery.
2- The Coach battery is kept charged by your built-in Converter (Charger), which in turn is powered by your 110-VAC.
3- Use a multimeter and check the voltage across the battery terminals. The voltage should be; 1- approximately 14.5 VDC if it is being charged, approximately 13.5 VDC if the battery is fully charged, and 12.5 VDC if the battery is not charged.