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Troubleshooting and Repairing RV Electrical Problems for the Beginner

Don is a retired engineer and long-time motorhome owner who enjoys helping readers deal with the increasingly complex technology of RVs.

A typical pair of coach batteries that you might find on an RV, and their connections. Two 6-volt DC batteries, connected in series, provide the 12-volt power that powers many lights and controls.

A typical pair of coach batteries that you might find on an RV, and their connections. Two 6-volt DC batteries, connected in series, provide the 12-volt power that powers many lights and controls.

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:

  1. Fuses and breakers
  2. The 12-volt system
  3. The power source
  4. Appliance current draws

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:

  1. 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.
  2. 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:

  1. You could cause an electrical fire and destroy your RV.
  2. 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.

The color of a DC fuse shows its amp rating.

ColorAmperage rating (amps)

black

1

gray

2

violet

3

pink

4

gold

5

brown

7.5

red

10

blue

15

yellow

20

clear

25

green

30

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.

ApplianceCurrentNotes

Air conditioner (rated 13,500 to 15,000 Btu)

12-14 amps

Peak use when starting up

Air conditioner

5-8 amps

Normal rate after it gets going

Coffee pot (maximum use, while perking coffee)

8-10 amps

Once the coffee is brewed, the hot plate under the pot uses much less power, especially if you turn its temperature down.

Hair dryer

8-15 amps

Less powerful hair dryers might be better for RV use.

Crock pot

1-2 amps

Crock pots are useful for cooking in RVs.

Food processor

3-5 amps

 

Electric frying pan

7-11 amps

 

Hand vacuum (small)

2 amps

 

Iron

8-10 amps

 

Microwave oven

8-13 amps

 

TV (digital)

1.5 to 5

Depending on the size, the manufacturer, and the technology.

Water heater (in 120-volt AC mode)

11-13 amps

 

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.

  1. 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.
  2. 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.

TermAbbreviationMeaningTips

Alternating current

AC

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.

Ampere

Amp

The measure of electrical current

 

Capacitor

 

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.

Circuit breaker

 

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

DC

Direct current flows constantly in one direction, commonly from a positive lead to a negative lead.

 

Diode

 

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.

Fuse

 

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

GFCB

Like a regular circuit breaker, the GFCB "throws" itself off when the current through it exceeds its designed current limit.

 

Ground Fault Indicator

GFI

Same as above

 

Ohm

 

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.

Watt

W

The measure of electrical power.

DC power can be calculated using the formula: W=V x I.

Wire gauge

 

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

LetterMeaning

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

In a resistor with four bands, the first three colored bands "spell out" a three-digit value for resistance in ohms, and the fourth band (if any) indicates the tolerance.

ColorValue

Black

1

Brown

2

Red

3

Orange

4

Yellow

5

Green

6

Blue

7

Violet

8

Gray

9

White

0

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 2008 Hurricane on a F53 Ford Chassis. My 12V system is only running when on shore power or on the generator. I may have shorted something when I hooked up the batteries as I saw an unusual spark. I have power to the use/store switch, but no power at the fuse panel under the rear bed. I can’t seem to find any breaker that is blown. I was told to trace the red lead from the coach batteries to the BCC on the firewall. Still no resettable breaker to be found! How do I resolve my RV's electrical problem with no resettable breaker?

Answer: Again, check that you connected the wires to the COACH batteries properly. Your symptoms point at the wiring being done improperly, or the batteries are actually dead. From what you have said, there should be no fuse or breaker problem if the RV operates properly when on AC Power.

Question: My coach is a 40 ft 2005 Monaco Camelot. I have an EMS Model 760 (00-00894-200). The display does not work sometimes. I have checked the voltage to the display board and it reads 12 volts. I have reset the EMS board at the breaker box. When I turn on the bedroom lights the display works and when I turn a couple of lights in the front room and kitchen the display works. I have also checked the EMS board J5 pins and everything looks good. Would I check for a short in the DC current?

Answer: OK, That EMS board is kind of old especially if it is original equipment. With your description of there being an intermittent operation, I would first look for loose or oxidized wires at the connections.

Also, always make sure your coach batteries are good and fully charged, as well as that they have water in them. Remember, your 12-VDC at the batteries should be around 14-5 VDC when they are charging, and around 13.5 VDC when they are fully charged, IF they are only at 12.0 to 12.5 VDC then many of your interior circuit boards will not work properly.

As a side note, you might consider using an external Surge Protector of you can't get your built-in to work properly.

Question: I have a 1999 Holiday Rambler Admiral. All fuses, resistor, are good, however, I have no power going to the fan switch on the dash for the blower for heat. There are no signs of broken or loose connections. Do you have any suggestions?

Answer: Your dash heater and its blower are powered by your engine battery. So, it has a fuse mounted in the fuse box that holds the fuses for the dash and engine equipment.

Typically, there is one fuse box under the hood that has the higher current fuses for the engine equipment. But, there is another fuse panel typically mounted under your dash that has more fuses for equipment on your dash such as; heater control, heater fan, front AC fan, dash radio, and other such equipment.

I suspect that if you find that fuse panel and check it for a blown fuse, you will fix your problem.

But, keep in mind that your heater/fan can wear out, and if the fuse blows again, you may need to have the electrical assembly replaced.

Question: I have a 2006 Triple E Embassy that we've had for about five months. The unit has 64,000 k and has been really well looked after. I'm hearing a clicking sound coming from under the passenger side dash about every ten minutes. Sounds like a circuit breaker type sound. There's no shore power hooked up at this time. Is this normal?

Answer: On my 2006 Bounder, I have some large fuses and relays in the exterior compartment below the passenger seating area. I assume your RV is wired similarly.

I have had a similar clicking sound in my Rig, and it was usually related to my DC Voltage level going to the 12-VDC electronics like my Surround Sound System, the Inverter, and such. Honestly, I have never been able to find the actual cause myself while hooked to Shore power in a campsite.

Question: I have a Jayco talon Toy Hauler, and my fuel station won't dispense fuel anymore when I turn it on inside the hauler the panel buzzes and the fuel station will make a noise but never pumps any fuel. Do you think it might be a bad ground wire?

Answer: Some of these TH's actually use automobile fuel tanks that have the fuel pump built into the inside of the tank. Others have external fuel pumps like with a motorhome and its generator.

Check if you have an external fuel pump and an external fuel filter on it. Often the fuel filter will clog up or "gum up" and need to be replaced.

Replace the fuel filter and then check that the fuel pump operates properly. This would be the most likely cause of your problem; a bad fuel filter.

Question: The exhaust fan and light over the stove don't work anymore. We have checked the fuse and its ok. Do you have any suggestions?

Answer: In an RV, the exhaust fan and the hood light are powered by your 12-VDC COACH battery.

The battery hot wire goes to the 12-Volt fuse panel which, is usually under the dash of a motorhome but will usually be near the other power fuse and breaker panels in camper trailers.

SO, if the specific fuse is OK then you should use a multimeter to check if there is a DC-Voltage reading on both sides of the fuse.

If there is voltage on both sides of the fuse, then you must assume you have a loose 12-VDC power wire going to these two electrical items, the fan, and the hood light.

Question: We have a 94(?) Security Penthouse. The interior lights seem to be hit and miss. I’ve checked the fuses, switches and bulbs with a multimeter. They all seem to be good. Plugs are all working. Do you have any suggestions?

Answer: I am not very familiar with a '94 Security Penthouse truck bed camper.

But, you can check if you have a separate battery in it for the camper lights, alarms and such. Newer models have a COACH battery and a Converter that keeps the battery charged when you are plugged into 110-VAC power.

So, check if you have a battery, and also check if it is in good condition; how old is it, does it have water, etcetera.

If you do have one and its OK, then check the Converter to make sure it is operating OK!

On the other hand, if you do not have this extra battery in your camper, then your interior lights are operating off of your engine battery. Then I would suggest that you check the cable connecting your camper to your Truck for power and make sure it is secure.

Question: I have a 1995 Coronado Pace Arrow and the running lights and headlights are not functioning, is there any advice that you can provide?

Answer: In the older motorhomes, the engine, drivetrain and the associated electrical equipment is pretty standard for the truck manufacturer used for all of this and the chassis.

So, for the lights mentioned, if you have a FORD or CHEVY system, you can have them service your truck equipment.

There is the standard fuse panel under the hood that normally holds the fuse you are looking for,

And, there is another fuse panel under the dash for those things on the dash area for all of those RV related 12-VDC items, such as; dash radio, dash fans, dash AC, etcetera.

Question: I moved into a small trailer. The built-in fridge and microwave do not work, but the outlets do. Where do I start to get the hose running again?

Answer: The microwave runs on 110-VAC, like the receptacles, while the fridge (if it's a 2-way) runs on either 110-VAC or propane. Try it on propane (LP). But remember, your fridge control circuit board runs to your trailer's 12-VDC battery.

Question: We have a 1989 chevy chieftain and recently the fuse keeps tripping for the panel for the hot water heater, water pump, hood light and fan is now not working. We tripped the main switch and it trips immediately. Any ideas?

Answer: The simplest thing to do is first turn ALL of these things OFF. Then see if the breaker that was tripping still trips with nothing turned on?

If it doesn't trip, then turn each of the accessories ON, one at a time to see which one is tripping the breaker.

This would get you down to the cause of your problem.

The Hood Light, Fan, and the Water Pump all run on your 12-VDC from your Coach battery.

Your How Water Heater heats using either propane or your 110-VAC and its control circuitry is powered by your COACH battery. Also, always keep water in the Hot Water Heater or it will turn itself OFF.

Question: I tried to run a small coffee pot off my 12-Volt system through an inverter plugged into the round 12-Volt plugin and blew a fuse. I’ve checked every fuse but all look ok. What else can I check? The plugin and radio are not working but the lights still do.

Answer: Some of these 12-Volt receptacles in RV's and in automobiles are only rated at 1-Amp or 2-Amp. They are there for small electronic devices and not for high current usage.

Also, Inverters are not 100% efficient an will allow even lower levels of current to the appliance used.

You should check your Inverter for a blown fuse on it first. It may have been damaged before the 12-Volt receptacle went bad.

Then pull the 12-Volt receptacle from the wall and check if the wiring insulation has melted. This could be a dangerous situation if it has.

At this point, it comes down to using a multimeter and check ing if there is 12-Volts at the receptacle, then if not, measuring the voltage at the output terminals of your 12-Volt panel.

Question: I have a 2016 Crossroads Cruiser. One of the electric awnings wxtends properly but won’t retract. We had it checked and was told that the motor is getting 12.5 volts when extending, but power is decreasing significantly when retracting. He thinks it is a pinched wire. Where do I start?

Answer: Your symptoms indicate the most likely problem is your COACH battery.

So the first thing you should do is make sure the COACH battery is in good condition and is fully charged. Many camper owners neglect this battery and let the water level get low and when this happens, the battery can get damaged internally.

Once you are confident that the battery I good, then you can go to other probable causes for the cause of your problem.

If you think your problem is a pinched wire, then examine the awning cable to the motor at each point where the awning arm is hinged and folds. If your problem actually us is a pinched wire, the cable should show where it is crushed.

I still suspect your battery.

Question: I have a 2009 keystone. When you have the air conditioner on and turn the lights on it all shuts off. What could cause this?

Answer: Your lights operate on your COACH battery 12-VDC, but so does your temperature control panel.

I suggest that you check that the battery is OK, ahs water iit and is fully charged. Normal operation of your Air Conditioner should not pull the 110-VAC dow enough to affect the Converter which keeps the battery charged.

Question: I have a horse trailer with living quarters. I thought my issue was with the battery disconnect switch, so I replaced it and the connectors to it, but still have the issue. When switched on, the lights won’t come on. I can hear a hum coming from the converter area. Off, on, off, on.... just the hum going off and on. Several times I have thumped the switch and the lights would come on. Could I really have bought another bad switch?

Answer: First of all, in an RV, the Disconnect Switch does not actually disconnect the 12-VDC line. It is a cheap low current switch that applies or removes 12-VDC to a higher current solenoid that can handle the current that might be going from your battery to all of your interior 12-Vdc appliances.

So, you might want to check that solenoid as being your intermittent problem.

As to your Hum? Converters typically do not make any noise(such as your Humming sound) unless they have a heavy load on them.

Check out the solenoid as being your intermittent problem and see if the solenoid takes care of this. Then see if the noise continues.

Question: I have a 2008 trail lite camper my meter tells me there is power coming in but nothing works. I have checked fuses, breakers, converter and outside plug all show to be good but still no power can you help me?

Answer: Probably the first thing I would check is my COACH battery. If it is dead, then a lot of the 12-VDC equipment will not work. Also, this battery gets its charge from your Converter, which if it has no 110-VAC to operate, the battery will die down.

So, from your symptoms, you say you have 110-VAC input to the RV?

If so, then check if you have 110-VAC at the input to the breakers in your breaker panel. If you cannot measure the voltage at these wires then you have an input power problem, in your campsite or your external power cable.

Also, go outside and reset the breakers in your campsite power box, just to make sure they are ON and your campsite has power.

Question: On a Ford E350 four winds I think I blew a fuse in the radio/backup camera, I checked the one under the hood, is there another one inline somewhere?

Answer: Most motorhome manufacturers will have an additional fuse panel under the dash, often on the left side that has fuses for the pieces of equipment that run on DC-Voltage which were added to the standard truck equipment. The RV backup camera is one of those pieces of equipment.

Remember also that most of this RV related equipment is powered by your COACH battery. So, check that this battery is fully charged.

Question: I purchased a 2000 Isata Motor Home and there’s no gas coming to the generator, what could the problem be?

Answer: First of all, you should replace the fuel filter and the fuel pump to your generator. These go bad or get "gummed up" often.

Your RV generator's fuel input line only goes down 3/4 of the way into your gas tank. So, make sure you have at least 1/4 tank of gas so your generator will get fuel.

Question: I have a 1993 Coronado that has 2 switches inside, one to turn the 12-volt power and one for the aux batteries. I can’t get any power going to the dashboard or ignition. I changed the switches still nothing. What should I check to fix the electrical problem with my RV?

Answer: The two switches are actually CUT-OFF switches for disconnecting your COACH (or AUX) and CHASSIS (or MAIN) power from the RV equipment so that the batteries are not drained while the RV is in Storage.

These switches actually control two high-current solenoids near the batteries which actually do the power switching.

But, they operate on your 12-VDC power (COACH batteries).

So, you need these batteries to be in good condition and fully charged.

You should check the voltage on the COACH batteries, right across the terminals and make sure they are in good condition, they are full of water, and the Converter is keeping them charged.

Question: Since getting a new inverter to prevent the RV batteries from going dead we have not been able to get power to the interior of the camper when plugged into a power source except for the interior plug-ins have power to charge things. Nothing else is getting power. Any suggestions?

Answer: You should remember that your Inverter get its 12-VDC from your COACH batteries, which are kept charged by your CONVERTER.

So, if you are not plugged into external AC-Voltage then your batteries will have a limited charge on them if you have a large load on them.

And of course, you are keeping your batteries in good condition; you know, full of distilled water, tight connections etcetera?

And always consider the old rule; "If it worked before I changed it or rewired it, then I probably did something wrong!"

Question: I have a 2017 GT Class A 369 that intermittently doesn't start and intermittently dies dead on the road. I replaced the chassis battery - no change. If I wait around 10 min, I can start and run it until it happens again, I had the chassis electrical checked out and they could not find anything wrong. Are you aware of any ‘safety’ switches in the coach of the GT Class A 369 that would prevent the engine from starting or kill it when it’s running?

Answer: First, No, I know of no Coach power systems or controls that will affect the engine or the engine battery. But, yes, your power stairs, your power awning, and your exterior lights are powered by your engine electrical system.

But, from my experiences with engine systems, if your alternator/regulator are not operating properly, you would get the symptoms you mention. But a competent Rv mechanic should have checked this first.

And considering you have already replaced the engine battery, I still go back to your Alternator/regulator as the most likely cause of your problem.

Question: I had a propane refrigerator in my RV catch on fire, and it did a lot of electrical damage to the bunch of wires located in the refrigerator area. I removed the appliance, and now I can't find the origin or the destination of about fourteen wires. They are mostly 100-volt, with some 12-volts. What do I do?

Answer: Your fridge only has two electrical connections that are not a part of the fridge itself; 110-VAC and 12-VDC.

All of the other wires are part of the fridge itself.

I wouldn't try to fix the fridge. If the electrical fire was bad enough to melt the wiring, you probably also have a bad control circuit board which will cost you at least $150 to $200 for the replacement part.

Also, if you had a propane fire, then the propane "stack" will probably be damaged, and the replacement part cost for this is usually around $800.

These costs alone are high enough to justify a replacement Fridge.

But, here's a long shot for you if you insist on trying to repair the fridge yourself; contact the fridge manufacturer and see if they have an electrical diagram of the wiring and maybe that will help you figure out the wiring. You see, most people never need this level of technical information to get their Fridge working.

Question: I bought a used 2004 hybrid travel trailer. The first time I tried turning the fridge on, the outside outlet directly behind the fridge shot massive sparks out, enough that neighbors noticed. The breaker in the trailer did trip shortly after. What could have happened?

Answer: I can only guess that if the receptacle is on one of the moving parts of your hybrid that you have "rubbed" the insulation off of one of the "hot" wires you could get sparks if these damaged wires touch the chassis.

If you remove the access panel on your fridge you may be able to inspect these wires for damage.

Question: My air conditioner breaker trips on my 2002 Komfort when turned on, what would cause this?

Answer: Being a 2002 model RV, your AC unit probably draws a little more current (extra 3-5 Amps) than it did when it was new.

Also, the AC breaker could be kicking out at a current as much as a couple of Amps lower limit.

But besides these possible "aging situations" your problem could just be with the AC unit itself.

As a long shot, remove the AC cover and check the following; 1- does the fan move freely, or is it stuck, 2- are there any worn or shorted wires visible, and the Capacitor could be bad and need replacement. While in there, you should clean the coils for better heat transfer when it does run.

I can't think of anything else that might cause the breaker to immediately kick-off, and you could be at the place where a new AC unit is your best bet for your future comfort needs.

Question: How do I troubleshoot a T-30 switch?

Answer: Your T-30 Switch is designed to handle the switching of high current (30-Amp) loads from Shore Power to Generator Power in an RV.

It is usually controlled by 12-VDC that is itself controlled by your power control panel.

The switch is normally wired to connect the Shore Power to your RV's power breaker panel. And when you start your generator, the power control panel will sense that it is running and then will apply power to the T-30 switch so that your RV is operating on the generator.

BE CAUTIOUS! If you are trying to troubleshoot this yourself, you are dealing with some deadly current sources. With this in mind, if you are trained to deal with electrical circuits, you could place a multimeter on the low-current connections from the power control panel. You should read 0-VDC when you are on Shore Power, and you should read around 12-VDC if the power control panel senses the generator power and applies the appropriate 12-VDC. If the voltage is there, then unplug your Shore Power cable, and everything should operate OK on the generator. If not, then your switch is probably bad and should be replaced.

Again, BE CAUTIOUS or hire a qualified Electrician to do this for you to be safe.

Question: I have a 2012 Thor Challenger. I suspect fuses for the dash fans and power mirrors may have been moved to an incorrect location in the fuse box under the dashboard. Where may I find diagrams for this fuse box?

Answer: The first thing you need to know is that none of the major RV manufacturers provide any wiring diagrams for RV owners. Their philosophy is that you should not be dealing with such things and you should have a certified technician troubleshoot electrical problems. Sorry, but this is the way things are in the RV world.

So, I can tell you that you should find a fuse box under your dash that provides power to the "non-drivetrain" electrical equipment such as your; dash fans, power mirrors, rear camera, and some other such equipment.

They typically use automotive-style fuses and make sure you do not change the value from the original used by the manufacturer.

In the past, I have had to draw a picture of the fuse box, and unplug the fuses one by one and make my own chart.

Question: We recently purchased a third hand Starcraft AR-ONE 14RB. When plugged into shore power, everything works. When running off the battery, nothing works. The battery is reading a full charge. Where should we begin?

Answer: From your symptoms, your problem should be either a broken or loose wire to the battery terminals, or your battery is actually bad and you should check it when under a load.

Question: Today I came home to my 2004 34’ 5th wheel, the air conditioner was on, but it was too cold, so I switched it off. The next time I was warm, I turned on the switch, and nothing happened, so I switched it off again. But now, with the switch still set to off, the air conditioner comes on, but no air blows out. Am I in danger? What is happening?

Answer: The first assumption we have to make here is that the AC and the temperature control panel wiring has not been "messed with" by anyone. The reason I say this is that a correctly wired system and a suitable control panel would not apply power to your AC.

So, if the AC is trying to operate then the odds are that 1- your Temperature control panel is bad; or 2- your temperature sensor on the interior wall is bad, or 3- you have a wire that has shorted to ground somewhere in the wiring system of the AC.

As t whether this is a dangerous problem, I could not say from what you have described, but I would get tie wiring checked.

Question: I have a 1999 Gulf Stream ultra class C. I have noticed that the internal carbon lights continue to work after I have disconnected the AC power source. I am guessing that they are running off the internal battery. Will these carbon lights run the batteries down or hurt my Gulf Stream RV in any way?

Answer: Yes, your interior lights operate on your COACH battery, which must be kept charged.

Typically of your battery is fully charged, you can use these lights and the other 12-VDC interior accessories for several days before you have to recharge the battery by turning your AC power on.

If you are storing your RV you should operate your 2 CUT-OFF switches which disconnects a number of accessories and equipment in your RV. One is the MAIN (or Chassis) and the other is the AUX (or Coach) switch.

Question: What would cause awning and jack to stop working ?

Answer: The typical motorhome uses the engine battery to supply voltage for the awning and usually the jacks of the RV.

With "Fivers" and travel trailers, they will typically be wired to operate on the coach (of House) battery.

If they stop working check that the coach battery is fully charged.

And, make sure that your converter is plugged into 110-VAC and is keeping your house battery charged.

Question: I have a 2007 Class A Coachman Mirada 350DBS, and the refrigerator light is on but not cooling. Also, the breaker is tripped and won't reset when I turn off/on. Is the breaker bad?

Answer: If your fridge is a 2-way, then try it in Propane mode. If that doesn't work either, then your fridge circuit control board could be bad. So, before going to the circuit board, go outside and behind the fridge. Remove the exterior weather cover behind the fridge, and check that you have 110-VAC at the receptacle that the fridge is plugged into. If the voltage is there when the fridge is unplugged, then you have a fridge problem overloading the 110-VAC of the RV.

Question: I have 120v to the AC electrical panel when hooked up to 120v shore power. There is 120v between every AC breaker and the neutral bar inside the panel, but somehow between the AC panel and the 120v AC outlets in the RV, the neutral is lost. I have 12v between the hot prong and the ground prong on all outlets, but not between the hot and neutral prong. How can I troubleshoot the electrical current problems in my RV?

Answer: First, check if the receptacles you mention are GFCI receptacles. If they are, then check the Master GFCI receptacle and then press the reset button to re-apply power to your Slave GFCI receptacles.

This is a common problem and if the reset button "kicks" off again, unplug all appliances from all of the Slave receptacles to fin which one has a low current leakage between the Common and Ground wires.

Of course, this has nothing to do with your other regular receptacles, but I would check the GFCI receptacle problem first. It gets power from only one of your breakers.

You didn't say so, but I assume your Air Conditioners operate? Or Not? They run on 220-VAC which is two 110-VAC lines and a neutral line.

Question: The rocker switch on the slide in my RV keeps burning up. Any ideas?

Answer: Without knowing anything else about your RV, I am going to say that you need to check out the control module for that slide.

In the newer RV's each slide is controlled by a module that the manufacturer can help you locate.

This module, with most RV's, is the same for each slide. So, the first thing you should do is swap this slides module with one of the modules that control your other slides. If the rocker switch burns up after a swap, then you need to look at the drive mechanism for that slide.

Question: Why do I have 130+ volts at my RV receptacles?

Answer: That's a little high and could cause some of your accessories or appliances to be damaged. Typically, you should have 110-VAC. You need to complain to the campground about their high voltage. I recommend that you have a Surge Protector inline with your campground power that can monitor this condition.

Question: My trailer slide and hitch are not working on direct electricity provided from my home. Everything else works (lights and fridge) just the hitch and slide. Could you please help?

Answer: The Slides and Jack operate on the same COACH battery. So, either your 12-VDC supply is too small, Orr the wiring for them still go to your battery and not your home supply.

Question: There was a lightning storm just now. My RV has no A/C power, and breakers on the electric box are on battery backup working. What can I check now?

Answer: First check that (hopefully) the breakers on the campsite power box have kicked and need to be reset.

If they are OK, then (hopefully) you have a Surge Protector inline with your RV Power Cord and just needs resetting?

Use a multimeter and check if you have ANY 110-VAC on the input wires in your breaker box. If there is NO power contact the campground office and have them send a tech out to check their power box. If YES then as a long shot, turn OFF all of your breakers and then turn all of them back on.

These are the most common problems, and you need to check them first. Hopefully, the problem is not inside your RV wiring.

Question: I have a 40-foot big horn hooked up to 110 and it worked fine for 3 months then randomly started tripping the gfci inside the house. Gfci's inside the house are working properly. I replaced the 2 adaptors and it blows gfci out. Could it be that the 50amp breaker inside the camper is bad? The 50 amp breaker inside camper doesn't trip but I'm unsure that 110 would have enough power to trip the breaker?

Answer: Many people don't actually understand the way a GFCI breaker operates.

They are designed to sense very low current flow between the COMMON wire and the GROUND wire of the GFCI circuit and anything plugged into them.

This is a safety measure and you will typically only find GFCI receptacles where there is a chance that you are using an appliance and can be touching ground at the same time, such as; the kitchen, the bathroom and on the exterior of your RV (or house).

The problem when you plug an RV into a house GFCI receptacle is that you are adding dozens of feet long cabling plus that in the Rv itself to the GFCI circuit and there can be problems that allow very small current leakage between these very long wires; sometimes enough leakage to make the GFCI you are using to kick out.

Here are a couple of things to try;

1- Check the connections of your RV cable and clean then to get rid of any oxidation or corrosion on them.

2- Make sure all of the connections on each end of your cable fit tightly into their sockets.

3- Unplug ALL of your 110-VAC appliances from all of your receptacles in your RV to see if one of them might be drawing too much current between the Ground and Common wires.

4- Borrow a friends RV cable and see if your GFCI operates properly with it?

5- If you're using cheap cable adapters, go to your nearest RV part store and get the ones designed for the potential current load.

If all else fails, you may just be the victim of aging interior RV wiring connections that allows this small amount of current to flow.

Question: I have a 2017 5th wheel toy hauler. After A 5 state long trip, once we landed home again, we've been experiencing problems with our fridge, microwave, and electric fireplace not working. We've checked gfi and breakers. We are just about to call a mobile repair to fix it. Any advice?

Answer: Seeing as all of the appliances you mentioned having problems with operating on your 110-VAC and thus through your breaker panel and your external service, I would first put a meter on the 110-VAC source for your Fiver.

The source voltages (two-220VAC inputs) should be steady and not varying at all, regardless of what you have running in the RV.

If you have and use a Surge Protector, many of them will indicate low or high voltages.

If you do not have a Surge Protector, then you need to use a multimeter to check that these input voltages do not vary.

Also, make sure you do not have too many personal appliances operating in your RV because this can pull your source voltage down. Unplug any unnecessary equipment.

Question: I have a 2018 Forest River KQBTS with no electrical issues as of last year when I bought it. I kept it stored outside and covered during the winter. This year, only the battery works. At first, the microwave clock came on, but then that stopped too. There are no fuse or breaker issues that I can find. Do you have any ideas?

Answer: First of all, if your microwave clock worked, then you must be plugged into 110-VAC?

So, check that your RV battery has water in it. Then measure the voltage across the battery terminals. It should be around 13.5 VDC if it is fully charged, or around 14.5 VDC if it is not charged, but the RV charger is running.

Once you have confirmed the battery system is operating OK, then you can check out your AC-Voltage problem.

I assume you have a 30-Amp service and that you are using a standard RV external power cord. It is important that you use a standard RV power cord and that you have it plugged into a standard 30-Amp power source like what you see in a campsite.

If you are using some kind of home extension cord and adapter, there can be problems with ground lines, and even the power lines you use. There are standard 30-Amp to 15-Amp adapters available on the web and at Rv parts stores. NEVER use an adapter that does not have the ground pin on it.

Question: My slide out fuse keeps blowing. It seems to only happen when connected to my truck. Is there a way to test trailer hook up cable?

Answer: First of all, if you're using a standard commercial cable to connect your vehicle to your camper, and it is not worn or crushed, then I would suspect the TOW WIRING installed into your Truck.

But remember that if your slide-out fuse is blowing, then this would be caused by something on the slide side of the RV wiring, and I would check that 1- the slide is moving freely, 2-the slide control module is good, and that the slide motor is not drawing too much current.

Question: I have a 2007 Salem LE 5th wheel camper. The air conditioner will not work if it’s turned to the auto position but will if it’s in the ON position. What would be the problem?

Answer: Considering how your temperature control panel operates, I would suspect that your COACH battery is not fully charged and this can cause the temperature control panel to act strangely.

Otherwise, your AC unit should cycle around the temperature you have set on the control panel.

Question: I have a 2004 Holiday rambler vacationer that I bought used about 5 weeks ago. After about three weeks of owning it, me my family took a 22 state 14-day trip the mechanic was unable to locate the problem after 4 days of tracing wires. Now my dash a/c, foglights, air horn, and leveling jacks will not operate or power on. These functions are in the same area of the dash and I assume are connected somehow. I don't know that much about electrical and new to rving. Any thoughts on my issue?

Answer: Well, your Holiday Rambler, regardless of whether it is gasoline or diesel powered, is pretty much a standard engine and electrical system for that truck manufacturer, such as Ford, Chevy, Cummins, Caterpillar, etcetera.

Your Dash AC, foglights, air horn and your leveling jacks are powered by your Engine electrical system.

Your problem should be easily found by that particular manufacturer's certified technician.

I would suggest that you contact the nearest service center and have them check out your problem. A certified technician should clear up your problem easily. By the way, I would suspect a blown fuse or two in the main fuse panel near the engine.

Question: I have a 2004 Bounder RV. The air conditioners work, but you have to baby it to get them started. At times, even with the air conditioners off, there's a clicking sound coming from the controller. Not constantly, just now and then. What would cause this is the controller or thermostat bad?

Answer: Remember that your Temperature Control Panel operates on 12-VDC from your coach batteries.

So, make sure your coach batteries are in good condition, full of water and that they are fully charged.

Your Bounder has a built-in converter that keeps the batteries charged. However, when the batteries are not taking a charge then the Converter can power a few of your 12-VDC items, but it cannot carry the load of everything operating.

This is the most common cause of this kind of problem with the temperature controller.

Also, as your air conditioners age they tend to draw more current, both in the operating mode as well as when the compressor cycles. With a 50-Amp service to your RV, your service should be adequate for operating your Air units, unless you have enough other 120-VAC equipment running that could put you near an overload condition on your campsite service.

Question: My RV batteries are good but I can't start the RV because there is no power. Then this morning it started what could be the problem?

Answer: Do you have a small solar trickle charger on your roof that keeps your engine battery charged? Many motorhomes do these days. Regardless, check your engine battery for low water level? And then check that your engine battery connections are tight and in good condition.

Question: Went to turn coach on. Nothing lit up on the dash. I replaced all three batteries. Lights on the dash now work. However the "transmission" light isn't on, but power is being supplied to it (vim box checked - power being supplied). Is the Neutral Safety switch causing the problem? If so, where is it? Is there something to be looked at UNDER the coach? Everything inside has been checked and has power. No fuses are blown. Allison Trans 3060.

Answer: First of all, I am assuming that your batteries were dead? If so, your RV computers that control everything may have lost some of their data.

Normally, most vehicles, RV's included will reset themselves within a few minutes.

Your diesel should be no exception, so after a bit, your engine should start properly if you have all of the peripheral things set right. I do not know what model Rv you own, but some things that can keep many motorhomes from starting are;

1- Is the transmission in park or Neutral?

2- Is the Emergency Brake ON?

3- Are the 2 Power CUT-OFF switches (COACH and CHASSIS) turned ON?

4- Are the Slides closed?

Check these things and then see if the engine will crank.

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: 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: 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.