Car Battery Died After Not Being Driven For 3 Days

If you haven’t driven your car for a couple of days, you may be wondering why the battery has died. Unfortunately, there’s not just one cause behind this problem, and in fact, there could be multiple reasons behind why this is happening.

So if you want to know why your car battery has died after 3 days, as well as what you can do about it, then keep reading!

What Could Be Causing Your Car Battery To Be Dying After 3 Days

Without further ado, here are all the different problems your car may have to help you figure out exactly what’s going on!

Parasitic Drains

One of the most likely reasons that your car battery may be dying after 3 days is due to a parasitic drain. Unfortunately, parasitic drains aren’t the easiest to find, and they tend to be in areas you won’t expect (such as the trunk lights being on constantly)

But if your battery is draining after a couple of days, then a parasitic drain could definitely be the culprit.

How To Deal With A Parasitic Drain

If you think that your car is suffering from a parasitic drain, then you’ll need to find the cause through a process of elimination.

To figure out where the drain is coming from, connect a multimeter to your battery and watch the voltage. While you’re watching the voltage begins pulling fuses one by one. When you notice the drain disappears when you remove a certain fuse, then you’ll know that’s where the problem is.

The Battery Is Weak Or Old

When was the last time you changed your battery? If you can’t remember, then this may be the reason your battery has died after 3 days. Batteries tend to lose the amount of charge they can hold as they age, so if your battery is old, it might just not be able to hold a charge anymore.

An old battery, in combination with a parasitic drain, is a recipe for disaster, and when together, they create the perfect storm for your battery to die rapidly.

What To Do When Your Battery Is Weak Or Old?

If your battery is weak or old, then the best thing to do is simply to get it replaced. If it’s completely drained after three days, then there’s a strong possibility it may even drain when you’re driving, and the last thing you need is to end up in the middle of nowhere with a car that won’t start once you’ve turned it off.

However, if you have an unsealed battery, you could try topping up the electrolyte solution. To do this, you’ll need to add 120 grams of Epsom salt to a liter of distilled water, ensuring the salt has diluted fully. It’s best to remove the old electrolyte solution and refill completely from scratch when doing this.

Bangkok, Thailand - August 5, 2017 : Unidentified car mechanic or serviceman checking a car battery for fix and repair problem at car garage or repair shop

Something Was Left On

Another extremely common reason that your battery might have died after three days is that you forgot to turn something off when you left it. For example, if the headlights or the radio remained on for a few days, it would be more than enough to completely drain the battery.

Even if you’re certain that you switched everything off, if one of the appliances in your car has issues, then it may have ended up malfunctioning and staying on!

Check The Electrics

Of course, the best thing you can do once you’ve charged your battery backup is to make sure you’ve double-checked everything has been turned off. It may even be worth checking on your car more often to see if something is on, just to be sure.

Remember, this could have also been a combination of a battery not having enough charge and then something being left on. If that were the case, the battery would die extremely fast, but it doesn’t mean it’s permanently damaged.

However, if the problem repeats itself, you should give your car the once over, and consider one of the other issues on the list!

Extreme Temperatures

While newer batteries don’t suffer from this problem as much, if you have an older battery, then it may have died in 3 days because of extreme temperature. Both hot and cold weather can completely kill an old battery, especially a battery with other underlying issues as well!

How To Deal With Extreme Temperatures

Unfortunately, if your battery has died due to extreme temperatures, it can be a lot harder to fix the issue until the weather improves.

If possible, you should try to move your car into an area where it is from the elements. If extreme heat is the problem, then try moving your car to a more shaded area, and if it’s due to extreme cold, then you should try to move your car somewhere indoors.

Again though, extreme weather only affects older batteries, so this could just be a good time to replace the battery altogether.


Another reason that your battery may be draining so rapidly is due to corrosion. If your battery has become corroded then it’s going to the alternator may not be able to top up the battery properly whilst you’re driving.

How To Deal With Corrosion

Fortunately, if your battery has corroded, then you can fix the issue. You’re just going to need some baking soda, water, and a stiff-bristled brush.

Once you have all three, you just need to mix the baking soda and water, until you’ve made a paste. When the baking soda and water have a paste-like consistency, spread it over the corrosion and then scrub the area with a brush and you’ll soon notice the corrosion disappearing.

If you notice that there’s corrosion on the terminal or cable connectors you can also use sandpaper to remove it. Eliminating corrosion in these areas is especially important to allow a good connection for electricity to pass.

Loose Connection

As well as corrosion, sometimes a loose connection can also cause the battery to drain faster, especially the connection is causing charging issues.

How To Deal With A Loose Connection

If you think a loose connection is the reason your battery is dying after three days, then you should perform a visual inspection. Making sure to check the terminals, cables, and connectors. Once you’ve found the loose connection, it’s then as simple as tightening it back up to fix the issue.

Remember, sometimes, around a loose connection you may also notice that there’s a lot of corrosion that can vary in color from blue, to white or green. If you notice that, then you should follow the steps above to remove it!

What Can Drain A Car Battery While It’s Off

You may be wondering what exactly could be draining your car battery when it’s turned off. But there are a few things that could be doing it. For example, the clock and onboard computer in newer cars will continue to drain the battery. So if you left it for a couple of days when it was already on a low charge, then they could have been the final nails in the coffin.

And all of this is in combination with a parasitic draw of some kind, then it’s no wonder your car battery died after three days.

(Find out why your battery died with an interlock.)

What Can Make A Car Battery Go Bad?

If you’re wondering why the battery died after three days, then you should also remember, there may have been something wrong with the battery, to begin with. Here are all the things that can make a car battery go bad!

  • Not using the car enough.
  • A parasitic draw somewhere in the car.
  • The battery is old (and has become weak)

And once two or more of these problems are in the mix, then the chances of the battery dying after a few days is going to increase dramatically.

How Can You Keep Your Car Battery From Dying When Not In Use?

If you don’t want your car to die after a couple of days again in the future, then there are a few things you can do to help prevent it from happening again! Such as:

Use A Trickle/Float Charger

One thing you can try when your battery is not in use is to connect it to a trickle charger or float charger. Doing this will ensure that the battery remains topped up when not in use while ensuring it doesn’t become overcharged.

Disarming The Alarm

If you know that your car is going to be stored in a safe location, then you can also disarm the alarm to help save some power while your vehicle is not in use. Just make sure the car is stored in a garage or somewhere similar with CCTV if possible.

Disconnect The Battery

And lastly, you can also disconnect the battery to stop any parasitic draws from draining it. This is particularly a good idea if you don’t plan on using your car for a few days. Just remember that if you do disconnect the battery then you’re going to reset all the electrical systems.


As you can see, there are a few reasons that your battery may have died after just three days. The most likely culprits are a parasitic draw, something being left on, extreme heat, or an old and weak battery.

Remember, if you think there’s a problem with your car battery, then it’s always best to take it to a mechanic to get fixed!

And if you liked this article, make sure you check out the rest of the website. Otherwise, have a great day!

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