It can be frustrating to have a brand new RV battery go dead. I mean, a battery is basically made up of lead plates and acid. How can that go bad straight from the factory?
The truth is that we have all experienced quality control issues on many of the products we purchase. We all know the saying, “They don’t make them like they used to!” Unfortunately, an RV battery is no exception, and there have been reports of battery issues or a dead battery straight from the factory.
However, Besides the battery itself as the issue, a dead battery could be caused by a defective charging system, which could be anything from a loose wire connection to a battery drain. This post will review the common causes of a dead RV battery and what you can do about it, including:
- Causes of a Dead RV Battery
- How to Prevent a Dead Battery
Whether you have an AGM battery, lithium, or the tried and true lead acid battery, the causes and fixes below apply.
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Even though the inside material of each battery varies, they are all deep cycle batteries that work the same for your RV. Some have a longer battery life, but if brand new, the expectation should be that they work properly with your RV.
Your RV battery is the main power source for most RV appliances and lights. A dead battery puts you in a tough spot to operate your RV, even when connected to shore power. The first step to fixing this issue will be first to discover why the RV battery is dead.
Step 1: Check if you have a discharged battery. An RV battery can discharge pretty quickly if providing power. The battery may have sat around for a while, slowing discharging. As your RV sits around, it still provides battery power to many things, including your radio and carbon monoxide detectors. If you want to see a complete list of what runs off a battery, visit what runs off a battery in a travel trailer.
First, check the voltage with a multimeter to test if you have a discharged battery. If you have a voltage ranging from 13.3v to 12v, that battery is considered charged and should not be causing battery issues. If you have below 12V, your battery is discharged and will need a charge.
The easiest way to determine whether you have a defective or discharged battery is to connect it to a separate charger. You want to use a separate charger and not the RV converter because you want to charge the battery from the RV independently.
To charge your RV battery, connect to the trickle charger and keep it on for at least 24 hours. Deep cycle batteries can store a lot of power, and giving it a slow and complete charge will let us see if there is an issue with the battery. It is not common, but a deep cycle battery can be overcharged. Check out my post on overcharging a deep cycle battery. Even if on a solar panel, give that a few sunny days to charge the house battery.
Once it has been 24 hours, disconnect your charger and check the voltage. You should be getting a voltage reading of around 13V. If you are not getting 13V, and your battery is still at or below 12V, the issue is likely a defective battery or possible sulfation.
Battery sulfation is a process that occurs when lead-acid batteries are not fully charged for an extended period of time or are left in a discharged state for too long. Even with a new battery, it could have been left uncharged for an extended period causing sulfation.
Some battery chargers, such as battery tender, have a sulfation setting that can help. To be 100% sure, you can take your battery to an auto parts store, and they can test it with a load. They have tests for both a car battery or deep cycle battery. The load test is pretty accurate and will tell you if the battery is defective. It will be frustrating to know a new battery is defective, but just like any manufactured product, it does happen.
If you are getting 13V or higher, that is good news, as the battery was likely just discharged and needed a good charge. Reconnect to your RV and see how the battery is functioning. If the battery keeps its charge while connected to shore power, your battery should be good. If you soon get the same dead battery, that will take you to the next step.
If you went through the process of charging and testing your RV battery, but still getting battery drain, the next step is to see what could be causing it.
Step 2: Check for battery drain. Above, we touched briefly on how your RV provided power to many components, even when just sitting there. Things like your radio and carbon monoxide detector can drain your RV battery in just a few weeks. These are known as parasitic loads. They suck up power just like a parasite and can leave you with a dead battery.
If you have a fully charged battery and have it dead after a couple of weeks (when not connected to shore power), it could be battery drain from the parasitic loads. To fix this issue, install a battery disconnect switch. These disconnect switches allow you to cut off the battery from your RV and avoid the unneeded battery drain.
Another reason your RV battery is dead could be a poor connection with your battery terminal. Your RV bounces on the road, and connections, especially your battery terminal, can get loose. Any loose connection will cause your battery to be unable to charge while connected to shore power, and eventually, the battery will go dead.
Step 3: Check for a secure battery terminal connection. Your battery (or jumper cables) should securely attach to the battery terminal posts. This is either a bolt or screw that should be hand-tight with a screwdriver or wrench with no wire movement. Also, check that the terminals are clean and have a good metal-to-metal connection.
A battery issue, like your brand new RV battery going dead, can be inconvenient at the RV park. A few common causes of this dead range from battery drain to sulfation. It is important to go through the three steps to see if you have a defective battery that needs replacing or if a weak connection or parasitic load drains your RV house battery.
Tony is an avid camper and RV traveler. He fell in love with camping on his first RV trip with his wife over 25 years ago. Tony loves sharing lessons learned and tips about RV maintenance and safe traveling.