Why Won’t Your Generator Charge Your RV Battery?

The power of a reliable, dependable generator is one of the most valuable things you can have in your RV. Your RV’s generator is essential to the onboard electrical system. Unfortunately, this complex gadget is prone to malfunctions over time. When the RV generator fails to charge the onboard batteries, this is one of the first symptoms of a problem. So what is the reason your generator cannot charge your RV battery? 

Your generator could have problems charging your RV batteries due to numerous reasons, including corroded battery terminals or damaged wires, batteries with an inability to hold a charge, faulty chargers, low electrolyte levels, or unclean batteries. You can avoid this by following some precautions and charging your RV battery properly with the generator.

Almost everything in an RV, from lights to water heaters, is powered by batteries, so if your RV generator fails to charge these, it can be a huge problem. This article answers some common questions about generators and RV batteries, explains why your generator has a problem charging your RV battery, and suggests steps to properly charge your RV batteries with a generator. 


Generator Not Charging Your RV Battery

In an emergency, having a generator on hand might be used to charge your RV batteries. Although recharging your battery may take some time, the generator may be a lifesaver if you’re in a pinch. 

Having a generator as a backup, the alternative power source, will help you avoid having to disrupt or end your adventures to find a town or campsite to plug in. So if it malfunctions, it can be a real hassle. There are many reasons your generator may not be charging your RV battery, which we listed as follows:

The Battery Connections Are Corroded

If your RV generator is not charging your batteries when hooked into mains power, you should inspect the connecting points of your RV batteries. A buildup of green or white corrosion can cause the batteries to be unable to charge or only receive a small charge. 

It may not even be a genuine technical flaw. The corrosion could just be preventing the RV’s electrical system from connecting properly.

Disconnected Battery

Many times, we do not check if every connection between the charger and the battery is secure. You may have not plugged the battery with the charger correctly, or it may have gotten disconnected due to some external force. Check the terminals and connect the charger properly to make sure the battery is not disconnected.

Your Batteries Are Faulty

Batteries have a limited lifetime. They are not intended to operate indefinitely. If your battery is old or has a damaged cell, you cannot rely on it to retain a charge for an extended period of time.

In other words, you must evaluate the possibility that the generator is charging the battery but that the battery is incapable of retaining the charge. It continues to discharge over time, even when the generator is turned on.

Faulty Charger

The charger has the ability to block the generator from charging the battery if it is faulty. Problems with the charger are difficult to diagnose because they can appear from a variety of angles.

Some generators, for example, have connections that connect the generator to the battery. To allow the generator to charge the battery, you must first purchase and then install these wires according to the directions in the manual.

However, this is not true for all generators. Some models’ charging circuits make such a setup unnecessary, though you can’t determine until you read the instruction manual. If it says you need a dedicated charging wire, the lack of such a cable is most likely the source of all your difficulties.

On the other hand, it isn’t always the case. You may also have generators with malfunctioning charges. A malfunctioning charger may prevent the generator from charging the battery.

Corrosion On The Circuit Board

Sometimes, your circuit board can also have corrosion on its surface. This can prevent the generator from charging your RV battery, so you need to check it if you can’t find any other faults in the system.

It is important to note that it can be a bit tricky and technical to find out whether there is corrosion on the circuit board yourself because you need to deal with small tools. You can consider a professional, but if you can find out yourself, follow these steps:

  • You must first remove the external casing. This usually entails unscrewing some small screws or freeing tiny metal clips.
  • If you discover a flaky white substance on the circuit board, you are most likely dealing with corrosion.

Error in the Voltage Regulator

Many individuals are unaware that the voltage regulator is critical to the charging process. This component regulates the amount of voltage that flows to the battery. It guarantees that the voltage produced by the alternator is sufficient to charge the battery.

As a result, if the voltage regulator fails, the battery may stop charging. It may also begin to drain at a much faster rate.

Your Breakers And Fusers Are Tripped

Check the breakers and fuses as well. Tripped breakers and blown fuses might impair the ability of a generator to charge the battery. A spike in electricity from the RV park’s shore power can occasionally trip a breaker or a fuse.

A generator can keep your home powered, even if some of the breakers have tripped. Because the generator is still giving power to some of their equipment, you may not check the breakers and fuses, but it is critical that you do.

Check each one to ensure it is in good working order. Sometimes the breaker or fuse itself is faulty and must be changed. If there is no evident defect in the circuits, you may want to test each one separately. Simply take out each fuse or switch off each circuit breaker.

Then, turn on the light switches or appliances for each circuit as stated. If they come on when you turn the breaker to “ON” or install the fuse, you may rule out a circuit breaker malfunction. If the relevant circuits in the RV aren’t coming on as they should, it could be a blown fuse or a blown circuit breaker.

How To Check If Your Generator Is Charging The Battery

First, checking if your generator is charging your battery before diagnosing any problems is important. To do so, you can use a voltmeter.

You can establish whether or not a generator is charging the battery using a voltmeter to measure the voltage across the battery. When the generator is turned off, the voltmeter readings should match. When you turn on the generator, the measurements should rise.

Measures to Ensure Your Generator Is Charging Your RV Battery

If your generator does not charge your RV battery, and you have diagnosed the problem, you can take some measures to solve the problem yourself. If you are unsure about troubleshooting your RV’s electrical system, seek assistance from a licensed RV technician. Otherwise, use our guide and consider the following measures: 

Battery And Connections Care

The battery’s recharge capacity and life are directly affected by proper maintenance. Maintain an eye on the electrolyte level and refill it with distilled water as needed. Keep the RV battery well charged and avoid less than 20% deep discharges to extend battery life.

If your battery connections seem to be corroded, the battery posts and connection hardware may need to be thoroughly cleaned. Follow the following steps to clean them properly: 

  • First, mix 2 tablespoons of baking soda and 2 tablespoons of water together to make a thick paste mixture for cleaning.
  • Disconnect the power and ground leads from the RV batteries with caution, and apply some paste to an old toothbrush or any other little scrubbing brush.
  • Scrub the battery terminals and attachment components gently to clean them thoroughly.
  • Allow the paste to rest for 5 to 10 minutes for maximum results.
  • After you let the paste rest for 5-10 minutes, wipe the terminals and battery down with a clean paper towel.
  • Connect the battery and generator again with the charger.

Battery Replacement

If you have an outdated generator, you should consider replacing the batteries, especially if you only use it occasionally. Batteries degrade with time, so if the multimeter indicates that the battery can no longer retain a charge, replace it. In this instance, you have no other realistic option.

To do so, the batteries must be replaced with fresh or reconditioned 12-Volt RV batteries. This necessitates opening the sealed battery and working with components that are not suitable for the normal individual, so you can find a battery expert who can recondition your batteries for a small fee.

If the voltage of the batteries remains constant at full charge, the problem appears to be a generator issue. More troubleshooting will be required in such cases.

Replace The Fuse And Circuit Breaker

If you have diagnosed the problem as a tripped or blown fuse or circuit breaker, you can replace both of them.

A blown fuse is simple to replace on your own. This method will be quick if you have some familiarity with generators and electrical gear. If the fuse is not the issue, investigate the breaker. A tripped breaker can also impact the generator’s ability to charge the battery.

The tripped fuse may be easy to replace; a circuit breaker, on the other hand, will necessitate a complete replacement and rewiring. The panel box may also require an upgrade. This process is not easy for an average person, so if you need to replace a circuit breaker, you should choose a professional and insured electrical contractor.

Ensure The Charger Is Plugged In Properly

Check that the battery connections haven’t come loose during a long journey in your RV. Ensuring that the charger is plugged in properly to your batteries and generator is the first step to discovering the problem of your generator not charging your RV battery. 

Sometimes there could be an external force that can let your connections lose, so before you investigate anything else, make sure all the connections are plugged in properly. 

Consult An Expert

If you can not find out or diagnose and solve the problem yourself, you should have the charger, battery, or generator diagnosed by a professional. They will decide whether it needs to be replaced. They will also ensure that it is correctly wired and that all connections between the charger and the battery are secure.

If you are unsure whether your generator has a special cable that connects the generator to the battery, study the handbook or contact the manufacturer. They will provide you with all of the necessary tools to ensure that the charger maintains the battery’s charge.

The average consumer is unlikely to be able to identify the causes of their battery’s discharge, so consulting an expert in this field is the best option. In many circumstances, the generator is equipped with a circuit.

Steps to Charge Your RV Battery with the Generator

It is important that you properly set up the system to charge your RV battery with the generator. To do so, you can use the video linked below or follow the following steps:

  • First, turn off your RV and engage the emergency brakes to prevent accidents.
  • Inspect and clean the battery.
  • Now to check the electrolyte level, you must park on flat ground. If the fluid level falls below the acceptable level, replace it with distilled water.
  • Turn off all breakers except the one that feeds the battery if your battery bank is wired into your RV’s 30 or 50-amp electrical system. This ensures that all of the generator’s electricity is sent to the battery bank.
  • Start the generator and let the smart charger do its thing. Additionally, keep an eye on your battery meter to maintain track of the battery level and avoid wasting fuel.


You can now determine and diagnose the problem from the article if your generator is not charging your RV battery. You can also hire a professional with any technical work or use our guide to solve these problems.