How to Spot the Signs of a Failing RV Converter and What To Do Next 

You don’t want anything to go wrong while you’re traveling across the country in your RV. But if there’s one thing you can’t afford to break down mid-journey, it’s your RV converter.

You can go with worn tires, water leaks, or a clogged toilet. But you can’t go with a bad RV converter. It’s what powers your RV so you can charge your phone and use your interior lights, refrigerator, and other devices that need a 12V DC current.

Without it, not only will you be unable to use your gadgets and appliances, but you could also drain and possibly cause damage to your coach batteries.

But what happens when the RV converter goes bad? Or better yet, how do you spot the signs of an ailing converter early so it won’t conk out on you while you’re traveling? 

We’ll answer this and more for you below.

Common Signs and Symptoms to Watch Out For

Common Signs and SymptomsThere are definitely early warning signs that indicate problems with an RV converter. So before things turn out from bad to worse, these are the common signs you should watch out for:

Dimming or Flickering of Lights 

There could be a number of reasons why your RV’s interior lights start to dim shortly after turning it on. It could be a sign that your batteries need to be recharged or there’s a problem with the circuit breaker or fuses.

But it could also indicate that your converter is going bad. Aside from dimming lights, a faulty converter also manifests itself through the abnormal flickering of lights on the dashboard.

Unusual Sounds 

Some humming and clicking sounds that come at regular intervals are normal for a working RV converter. However, irregular and excessively loud noises are not.

Unusual sounds could be an indication of an internal problem with the converter. In most cases, it could even make a loud puffing noise or produce smoke. 

Unusual Smell 

Dimming or flickering of lights don’t necessarily indicate an emergency situation, but when you smell sulfur or something similar to burning plastic, it’s a different case altogether, especially if you’re connected to shore power.

It means your batteries are overheating or there’s a burnt or melted coil somewhere. Disconnect your RV from shore power immediately (it could catch fire if it gets hot enough) and turn it off completely before doing further exploration and testing.

Troubleshooting the RV Converter 

Troubleshooting the RV Converter There are several troubleshooting techniques you can do to know if your RV converter is failing:

Check The Converter 

To isolate converter problems from bigger electrical issues, plug your RV into shore power, then, check your television or microwave. Are they working? 

If they’re on but your lights aren’t, it means your RV has power but the converter isn’t converting it to 12V DC. Ultimately, this would lead to a converter issue.

Another thing you can do is use a multimeter and one-handed circuit tester to diagnose converter issues. By measuring the amperage, wattage, and voltage of your converter with these tools, you will be able to determine if it needs maintenance or replacement.

The other components you should check in your RV’s converter include the circuit board, resistors, diodes, and DC (direct current) accessories.

Once a converter issue is confirmed, get it fixed asap. Otherwise, a malfunctioning converter can hinder the operation of electrical components, or worse, damage onboard batteries as well.

Inspect The Battery

The job of a converter is to keep the RV batteries fully charged. It also reduces the drain of power from them. Once your battery fails to hold a charge, it can appear as a power converter issue. 

You need to fully charge your batteries and then disconnect them from each other to check their condition. If you don’t, the bad battery will draw charge from the good one making charging issues harder to identify.

Let the disconnected batteries sit for some time before checking them with a multimeter. It should read around 12.7 volts. If the reading is dropping, it means you have a faulty battery because bad batteries won’t be able to maintain a constant charge and must be replaced.

Inspect The Circuit Breaker or Board

A faulty circuit breaker can also affect your RV converter so it must be checked as well. To determine if it’s faulty or not, open the circuit breaker starting with the primary input breaker. Can you see any signs of physical degradation?

If there’s no obvious damage, close it up in reverse order so that the primary input breaker comes last. Then disconnect the AC power supply from the pedestal and remove the electrical panels so you can look at the backside.

If you see acid or corrosion on the wire terminals or connector tab, it could be causing your RV converter problems.

Check the Fuses

Electrical fuses are designed to handle a specific level of current. Power surges and short circuits can burn the fuse and make the converter unable to work properly.

Watch Out for Faulty Resistors and Diodes

If your converter makes use of resistors, check them as well. Resistors help the converter control the voltage of your RV’s onboard batteries and electrical system. If they are faulty, battery cells will be unable to hold a constant charge. 

Diodes, on the other hand, prevent your batteries from blowing up by allowing the electric current to flow only in one direction but preventing it from going in the other direction. 

Severe corrosion (white acidic residue) on diodes and resistors can make your converter unable to function and replacement of the entire converter might be your only option. However, if you get a reading after testing the diodes and resistors with a multimeter, it means they are working. 

Take note, though, that diodes are difficult to test even by experienced technicians.


Test The DC Output

You can troubleshoot the DC output by locating the positive DC output wire that connects the converter to the DC fuse block. Then, slowly poke the tester into the output port where the wire is coming from.


If the DC output doesn’t light up the tester or if it doesn’t display the right voltage, then it means your converter is malfunctioning. Remember to do this troubleshooting technique while the circuit tester is out and connected to your battery.


Observe the Converter Fan

A converter that’s overheating will stop working pretty quickly. One of the causes of overheating is if it has a malfunctioning cooling fan.


To check if the cooling fan is working or not, plug your RV into shore power and wait. The fan should turn on from time to time to cool the unit. If it remains off after some time and the converter starts to feel how to the touch, then the cooling fan is causing your converter to act up.

Repairing the RV Converter 

If you find trouble after doing these troubleshooting techniques, here’s what you should do:


Clean the Corrosion on Resistors and Diodes 

You can clean up any signs of corrosion on the connector tab, resistors, and diodes by adding one teaspoon of baking soda with 12 ounces of water. Use, a toothbrush to scrub the affected area with the baking soda solution.

Once free of corrosion, let it dry naturally. It should take around seven to ten minutes to dry completely. Then, check if it solves your RV’s converter issue. 

Replace Blown Fuses 

Luckily, burnt fuses are easy to replace. They are also cheap to buy. 

Make sure to replace them with something of the same current rating. If you use a higher amp rating, it will likely cause damage to the sensitive components of your RV’s electrical system—including the converter itself. Usually, though, RVs use 5, 15, and 40-amp fuses.

Reset Your Circuit Breaker 

If you find that the issue is a tripped circuit breaker, you will need to cool it down and reset it. If your breaker doesn’t reset or if it trips again or sees an electric arch after plugging the converter back in, it’s likely your converter needs to be replaced.

Replace Your Batteries 

The power that exits the converter should be between 11 and 13 volts. If there are no issues with your incoming power but your battery is still below 11 volts, you may have to replace your batteries. 


Replace Your Converter 

Your resistor gates are sure to be malfunctioning if you spot severe white acidic residue in your RV’s power converter. In this case, you may have to replace your converter your entire converter.

A Well-Maintained RV Makes a Camper Happy (H2) 

Replacing a converter isn’t easy or cheap. To avoid the hassle brought on by a faulty RV converter, it’s best to do an occasional preventative inspection. 

You want to find the trouble while you’re parked in your driveway than when you’re 25 miles out of nowhere. Remember: a well-maintained makes a camper happy!

Scroll to Top