How To Tell If Your RV Power Converter Is Bad (Symptoms)

In an RV or trailer, you have two different electrical systems. Some features and appliances are fine running off of 30 or 50-amp 120 service, but not everything can use that power. You need a power converter to make sure all electrical devices will work all the time.

One sign that will clearly tell you that you have a power converter problem will be the lights dimming all the time. When you see those lights go low and then bright again, and this keeps happening, then check your power converter to see if it is failing.

To learn more about this topic, just continue to read our article. It explores the issue, so you have the most important information on this topic. Once you get this information, you will know what to do when you see the different signs telling you your RV’s converter is going bad.

What is an RV Power Converter?


We know that just about every article written on this topic and device will have this section. These few words are for those who are new to the RV lifestyle and may not be sure what a power converter is.

The name is very straight forward when it comes to the purpose of this device. Your RV or trailer runs on two different electrical power structures. One is DC 12-volt current, and the other is AC 120-volt current.

The two cannot run off the same power source. That means you have to have a power converter to turn the AC 120-volt power into DC 12-volt power. This needs to be done no matter what level of AMPs you are using.

Once the power converter converts the AC power to DC, then you can recharge your batteries, power appliances, lights, and other features that use 12-volt power to run different components.

The power converter is a very important part of your RV or trailer, and without it, your camping lifestyle would be downgraded immensely. It is important to do regular checks on this device to make sure it is operating as it should.

Then watch for the upcoming signs that tell you that there is a problem you need to address.

Do RV Power Converters Go Bad?

The obvious answer is yes, it does. This is an electrical device, and even though it may not have moving parts, its components can still wear out. This process may take a few years to show itself, but it also can happen quickly if there is a connection or power problem.

When the converter starts to go bad, you will see some visible signs telling you exactly where the source of the problem lies. It is not going to be that difficult to find the source. Even a novice electrical handyman should figure out what those signs mean.

Once you see those signs, the hard work of discovering which component is failing begins. Being an electrical device, you know you will have to check different electrical parts like wires and connections, as well as check the voltage supply and so on.

This means you should have some good electrical meters in your toolbox to help you find the specific source of the problem. If you are not experienced at working on electrical devices, don’t mess with your power converter.

It is possible to turn a simple and inexpensive to fix issue into a major and expensive to fix the issue. If you do not have electrical experience, do not assume you do because you can fix simple wire and connection problems. The power converter is a whole different ball game.

How To Tell If an RV Power Converter is Bad


Here are some of the signs that you will see when the converter starts to go bad.

1. The lights are dimming- this is the most common sign that you will see take place. The interior lights will keep getting dull over a short period of time. But this may also be a battery problem, but usually, it is the power converter.

2. The batteries drain quickly- in this situation, the batteries may not be recharged by the converter. When that happens, you do not get a lot of power use out of the batteries, and you won’t be able to run many 12-volt features or components.

The other issue this sign is telling you about is that the battery may not be able to be recharged or hold a charge. In that case, replacing the battery may be your only option.

3. Power converter cooling fan- while this part can be damaged fairly easily, the usual culprit is a bad converter. If the converter is heating up and you do not hear the fan running, then you know there is a problem with the converter.

The fan may have to be replaced, or its motor will. This problem lies on the AC side of the system.

4. A bad control or circuit board- this component may be beyond many DIY handyman’s skill sets. It is a technician-level source, and it can get clogged or have faulty connections that only a technician can troubleshoot.

If all the other components check out okay and still run, then this part may be the source of the trouble.

5. Defective diodes- these little components help the electrical power flow in one direction. When they go bad, then your converter cannot work properly, and you will see some of the other signs take place.

6. Faulty resistors- some converters still use these components. If they go bad, then the converter won’t work right. A multimeter is needed to check to see if they are faulty or not.

You will want to have a reading between 3 and 13 volts for the resistor to be okay. These parts are a little difficult to replace due to their construction and placement.

7. Fuses- if you are not getting any power out of your converter, then it may not be that device that is failing. It could be that the fuses blew and shut off all electrical transfers. Replacement of the fuses is the cure.

8. Replacement- this is the worst-case scenario, as the converter may be beyond repair. These devices are not cheap. Leave the replacement process up to the technician, as it can get a little complicated to do.

Bad RV Power Converter Symptoms

The biggest symptom you will encounter would be the loss of electrical power to your 12-volt systems. This loss of power will affect those appliances that are propane only.

The reason that is so is that most, if not all appliances and other gas-powered features need electricity to run their operations. Any control boards installed need 12-volt power to work, as do any LED lights or your RV’s interior lights.

No matter the device, if it needs 12-volt power, then those appliances, lights, and other features will not operate. You will need to use a multimeter, a circuit tester, or a volt meter to diagnose the specific problem when you see these features, etc., not working properly.

It is possible that you bought an RV or trailer that had a bad power converter installed. Or you just happened to buy a replacement that turned out to be bad right out of the box.

This is just the way life can sometimes go when you own an RV or trailer. Anything can happen, so test the power converter before you buy your RV, etc., or a new device. It is a precautionary measure to help avoid bigger problems when you are camping.

Can a Bad RV Power Converter Reverse From Positive To Negative?


It is possible, but the source of the problem may not be the power converter. It is rare that a bad converter will reverse the polarity in your 12-volt electrical system. Rare but not impossible.

In other words, it could happen under the right conditions. The more common source will be in the 12-volt system itself. The conditions that would cause the converter to reverse polarity would be a power surge, as one example.

It is wiser to look at your 12-volt wiring and do not limit the search to the battery terminals. Normally, the problem would be a loose wire that somehow touches a metal part or another wire and causes a short that blows the reverse polarity fuse.

Finding that wire may take some time, as it could be anywhere in your RV. The fix would be simple. Just tighten the wire properly, and your system should work fine.

If all the other systems are working, then you may have to replace the power converter to fix the problem.

Common RV Power Converter Problems

The first common problem would be that the power converter is just bad. Something happened to it at some point in time, and it just does not work right anymore.

With all the components inside the converter, this is a real possibility. Wires get loose and crossed, connections get loose, something wears out, and soon, you are replacing the entire device.

In some cases, replacement is the only fix. Now we have talked about some of these problems earlier. When it comes to electrical devices, you have your usual suspects.

1. The battery- it may not be recharging well and does not have full power. When the battery goes bad, then you have to replace it. But check the cables and terminals as well to make sure they are properly connected.

Those terminal connections may not be right or tight and need minor adjustments to solve the problem.

2. Check the Fuses- usually, there are about two fuses in a power converter. They can blow at any time and for any power-related reason. If this is the problem, replacement of the blown fuse is your only fix.

3. Check all connections- loose wires are a common problem and can ruin your day if they short out the power converter. Double-check all connections to make sure nothing is amiss. And everything is tight.

4. Diodes & resistors- these are small but very important components in your power converter. They make sure the electricity is running at the right voltage levels as well as in the right direction.

If these have gone bad, you will have to have them replaced, and this is usually a technician-level repair.

5. The control board is bad- for some reason, this is a part, no matter where it is placed, that is always failing. The reasons this is so vary, and when the control board goes bad on any electrical device, then you will have a problem with your lights and other 12-volt features.

This is another technician-level repair.

The RV Power Converter is Not Charging The Battery


There are many reasons why you are facing this situation. Most of the sources for this problem can be easily fixed by you, but not all of them can.

1. Corroded battery connections- just clean them up to see if that solves the problem

2. The battery is bad- if it fails to hold a charge, then it is not the converter's fault. You would have to replace the battery to fix this problem.

3. Converter cooling fan fails- the fan keeps the converter from overheating. If it does overheat, it won’t work right, and the converter won’t charge your battery.

4. Converter thermal system fails-also a key component that helps the converter to work right. When it fails, do not expect to see your battery recharging.

5. Circuit board corrosion- just clean it up to see if that solves the problem. If not, you may have to replace the circuit board.

6. Bad diodes, resistors, or circuit boards- these parts can go bad and interfere with the converter’s operation. A technician may be needed to troubleshoot these little parts.

Like all other electrical devices, you should check the fuses and the breaker to make sure they are okay. The breaker will have more electrical components not working if it tripped, so that is easy to diagnose.

RV Power Converter Noise

This is a common issue that may not appear for a couple of years after you purchase your RV. The source of the problem seems to be the common design of the converters.

The humming noise you hear is due to the frequency the electrical parts are designed to work. That is why the hum may go away when you turn a light on or off.

Since this is a common design problem, too many RV owners have replaced good converters with new ones only to find out the new converters will hum as well. There are three options available to solve this problem:

1. Live with the noise- there is not much you can do about the noise, especially when your converter is older. You can apply load to the converter to help stop the hum, boondock, or unplug different devices.

2. Let a technician handle the problem- the parts inside are not made where you can work on them. Let the technician investigate and solve the problem.

3. Replace the converter- this may temporarily solve the problem, but it will relieve you of the humming noise all converters make at some point in time.

This is a very common problem, and you are not alone if you hear it in your RV or trailer.

The RV Power Converter Fan is Not Working


This is an electrical device, and it does not generate its own power. That means you have to check your power sources to make sure power is getting to the converter and then onto the fan.

Using a multimeter or volt meter will be the best tools to diagnose this. If there is no power getting to the devices, then you need to check your power sources. The fuse, the battery, and even the breaker could be at fault here.

Or you have a loose AC connection that cuts the power. Another source would be the temperature sensor. It may not be working right and giving false information to the cooling fan.

When that happens, your fan won’t turn on, and your converter may overheat. Replacing the temperature sensor may be your only repair option. Or the control or circuit board has gone bad, cutting off the cooling fan.

There may be other sources for this problem, so check all the usual common electrical problems, including the fan motor. It may have decided to quit and won’t power the fan.

Some Additional Words

The RV power converter is an essential device if you want your RV appliances and other features to work right. Keeping an eye out for the different signs that there may be a problem with the converter should be part of your regular maintenance schedule.

Some of the problems are easy fixes that you can do yourself. But on the more difficult sources for the problem, leave those for the qualified technician to handle. They have the tools and training to handle those repairs.

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