RV Battery Not Charging While Plugged In – How to Fix?

It could be frustrating to see the RV battery not charging while plugged in. Because ideally, it should recharge when hooked up to a shore or any external power source. 

There could be several reasons why you’re probably facing it. Luckily, you could diagnose and troubleshoot most of these on your own without reaching out to an expensive professional!

Here we’ll talk about how you can test the complete battery unit and find out some common problems along with their DIY fixes. 

We’ll also mention conditions where you can’t reasonably repair yourself and will need a certified professional to do it for you.

RV Battery Not Charging While Plugged In – Possible Reasons

RV Battery Not Charging While Plugged In

Let’s begin with some common possible reasons why your RV batteries aren’t probably charging when plugged in.

  • Corrosion in the battery terminals
  • The battery can’t hold a charge
  • Burned out wires or fuses
  • Cooling fan or thermal sensor damage
  • Circuit breaker issue
  • Circuit board or its component failure
  • Shore power source or converter issue

RV Battery Not Charging While Plugged In – How to Fix?

We’ve seen some common problems above. Now let’s find out how you can inspect them and do the fixes. 

Doing them will most likely get your RV battery to charge again when plugged in unless the battery is fully damaged.

RV Battery Not Charging While Plugged In

Make sure to unplug your RV from the power source before doing any inspection.

1. Check for Corrosion

A corroded battery terminal can prevent your RV battery from connecting to the rest of the RV system. 

Check for Corrosion

Inspect the battery and its terminals in the following way —

  • Locate the battery unit and check out its terminals to see whether there’s any white flaky substance or some other kind of buildup
  • If you see any such build-up, it’ll require you to clean the battery terminals and other attachments properly

Fix 

  • Mix two tablespoons (for each) of water and baking soda and make a thick paste
  • Disconnect the RV batteries from the system
  • Take a wire brush and rub the paste on it
  • Scrub all the battery attachments and terminals (gently, of course)
  • Once you see the buildup or corrosion is removed, leave it for 10 minutes
  • Wipe clean the components and terminals with a clean towel
  • Reconnect the battery unit and the components to the system

2. Check the Battery Condition (If It Can Hold Charge)

If you’ve cleaned the batteries or already have a pristine set installed in your RV, you could still see the battery not charging when hooked up to the power source. Why?

Check the Battery Condition

Because the problem is probably with the battery condition and it can’t hold a charge. To inspect this issue, you can do the followings:

  • At first, hook the batteries to a charger and charge them for around 7-8 hours
  • After getting the batteries charged, disconnect them from your camper
  • Now take a multimeter or a voltage meter  after an hour or so and connect it with the battery posts (the redone with the positive and black one with a negative)
  • Monitor the voltage reading to see if the charge level stays the same or discharging quicker than expected
  • If the reading is stable, then the battery is fine, but you likely have a problematic battery if the reading drops unexpectedly.

Fix

  • If the battery isn’t holding charge, you’ll have to take it to a technician or most probably replace it with a new or reconditioned one.

3. Check Wires and Fuses of the Converter

You can visibly check the wires and inline fuses of the converter. Do the following things while inspecting:

Check Wires and Fuses of the Converter
  • Look for any loose, damaged, discolored, or melted wires
  • Check if there’s any bare wire touching each other
  • Also, check out if there’s an inline fuse that may have blown

Fix

  • If you see any loose wire connection, you’ll have to tighten it properly. But if the wires are damaged in any way, you’ll have to source the exact same replacement.
  • For a blown a fuse, you’ve to replace it with a fuse having the same amperage.

4. Check Cooling Fan & Thermal Sensor

Now it’s time to check for any failure in the converter’s cooling fan or its temperature sensor. Both these components are responsible for cooling down the converter while charging. 

Check Cooling Fan & Thermal Sensor

You can do the following to inspect them:

  • Look for smelly, burned out, or faulty wire
  • See if the converter has become overheated after use
  • Check out if there’s any potential damage in any of the fan components
  • Use the multimeter to check if the fan’s getting current from the power source
  • Also, check the temperature sensor using the multimeter to see if it’s getting current

Fix

  • If any of the above inspections indicate any damage to the fan or thermal sensor, you need to replace them by sourcing a similar one.

5. Check the Circuit Breaker

You should be able to locate the breaker box of your RV. It’s similar to the breaker at home. To inspect for an issue in the breakers, do the followings:

Check the Circuit Breaker
  • Physically touch the breakers to see if any of these are tripped
  • Switch on all the lights and appliances in the RV
  • Make sure all of the circuits are in ‘on’ position
  • If there’s any appliance that’s not working after turning the circuits on, then there’s an issue with the circuit breaker.

Fix

6. Check the Circuit Board and Its Components

You may or may not fix the circuit board issues on your own, but you can certainly have a good look at it.

Check the Circuit Board and Its Components

To find out a bad circuit, you need to do the followings:

  • Test each circuit individually by removing each fuse or turning each breaker to the ‘off’ position
  • Turn on lights or appliances for respective circuits
  • Now see if all of them work when the breaker is turned to ‘on’ position or fuse is installed back
  • If they work, then there’s no circuit breaker issue, and you should check for any burned-out diode or resistor on the board.
  • Now, if you don’t see any burned-out components, you’ve to look at the board by removing its external housing.
  • After removing the housing, check out if there’s any white substance on the board. 
  • If you find any white substance, then your circuit board is corrupted and needs cleaning.

Fix

  • If there’s an issue with the diode or resistors, you may have to use a soldering iron to soften the holding of the blown component and then install the same replacement (ask an expert if it sounds too technical).
  • But in the case of a corroded circuit board, you’ve to prepare baking soda water for cleaning corrosion. Then, use a clean cotton cloth or paper towel to clean the white substance gently. Finally, use another clean paper to wipe dry or leave it for some time to air dry. 

7. Check the Power Source and Converter

Sometimes there could be problems with the source itself. So you must check if there’s any problem with the RV shore power or the converter.

Check the Power Source and Converter
  • Inspect the power posts of the shore power source and see if there’s any sign of a burned-out outlet that’s preventing AC current to the converter.
  • Also, check the power converter using a voltage meter to see it produces 13+ dc volts or see it shows any warning signs like dimmed lights or failed vents.

Fix

  • If the power post is damaged, you need to hire a technician to repair it or use new shore power.
  • If the problem is with the converter, you’ll most likely have to source a new one.

RV Battery Draining While Plugged In

If you see your RV battery drains while plugged in, it’s quite evident that it can’t hold a charge. You can further test it using the multimeter, as we’ve discussed in one of the instances above.

RV Battery Draining

For a damaged battery, after several hours of charging, you should see that the voltage reading is dropping quickly when you connect the battery terminals with a voltage meter.

And in such cases, you’ve to buy a new battery and replace the old one.

How do I Know if my RV Converter is Charging my Battery?

Now let’s see how you would understand that the RV converter is charging the battery properly. For a successful charging, consider the following instances:

RV Converter is Charging my Battery
  • If your RV converter is charging your battery properly it should be able to power up your RV and other appliances. And that battery shouldn’t be dead or depleted at an unexpected time. But if you see it fails to do so you can test the battery to find out whether it’s charging properly or not.
  • You can use a voltmeter or multimeter to test across its terminals. When you connect the terminals, it should show a reading of 13+ volts or around 14 volts DC power when charged properly. If it’s not discharging rapidly, then the converter is good to charge the battery.
  • You can also check the DC distribution panel of your RV by connecting it to the multimeter. If your converter properly charges the battery, you should see the power successfully changing from AC to DC.

How can I tell if my RV converter is bad?

It’s possible to see your brand new RV battery dead due to a bad converter. Luckily, you could find it out by looking at some warning signs, some of which include the followings:

RV converter
  • Lights and appliances in your RV are not working properly
  • Indicator lights around the converter dashboard are dimming or flickering
  • The cooling fan isn’t working
  • Internal air vents not functioning

Final Verdict

In this article, you’ve seen all the common causes why your RV battery won’t charge. Although these issues could give you a big headache, you’re now well familiar with how to get rid of them.

Some of these problems aren’t major such as the corroded terminals, corroded circuit board issues, fuse issues, or cooling fan issues. 

However, problems like damaged circuit boards, breakers, or the battery not being able to hold a charge; are something you can’t deal with on your own. And you probably need to hire a professional.

Besides, some RV batteries and converters today come sealed and can’t be checked by DIYers. But again, figuring out the issue yourself can help you stay one step ahead!