Car Battery Drain

8 Things That Will Drain Car Battery

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If you’re an enthusiast driver, then I believe you’ve once experienced a sudden power surge at a time when you needed your car the most. Most motorists have posted this kind of experience in most auto forums where the battery fails to start even after turning on the ignition. If you’re not aware of it, this is basically a car battery drain.

Now, your car’s battery is similar to any other battery. The amount of charge it has doesn’t last forever. But, regardless of this, there are certain scenarios where the battery drains faster than usual making it impossible to supply power to your car’s electrical components.  If this is what you’re going through, then it means there’s a parasitic battery drain in your car’s electrical system.

If you’ve read up to this point, then there’s no doubt you’re curious to know what the reasons might be. Thankfully, this short guide has conducted extensive research to find out what exactly could cause your battery to drain. Here are 8 factors that can be possible causes.


8 Things That Will Drain Your Car Batteries

But First, Why Do Batteries Die?


Although the list of factors that cause your car battery to die is endless, they can be shoehorned into three major categories. These are battery problems, driver or user error, and lastly electrical system problems.

While some of these errors are easy to troubleshoot, others are quite demanding and will hence require invention from an expert mechanic. So, before you pick those jumper cables to boost your battery, here are eight things you need to be aware of.


  1. Driver Error

Driver oversight or human error is one of the reasons that cause a car battery to drain unexpectedly. You see, when you drive home from a long day at work, there are times when you might forget to turn off the headlights, lock the doors or close the trunk.

Since these components rely on your car’s battery to stay alive, they’re likely to share the available power overnight leaving your battery completely depleted by morning. So, before you point your fingers at anything, you should first confirm if you left the headlights on or if you forgot to lock the doors.

Thankfully, most modern cars have alert systems that notify you to turn off all electrical components. Others have smart sensors that shut these components off after some time.


  1. Aging or Weak Battery

If the low power problem is not caused by driver’s error, then another possible cause is an aging or weak battery. In humans, we call it aging. But when it comes to batteries and other non-living things, we call it wear. You see, your car’s battery is not designed to last forever.

It has an expiry date or rather a lifespan, which in most cases ranges from 4 to 5 years. So, once your battery gets to this age bracket, it automatically becomes weaker and unable to hold a full charge for too long.

And since this problem can leave you stranded in the middle of the road, you must address it immediately by buying a new battery that suits your car’s specifications.


  1. Faulty Charging System

Your car’s battery is responsible for providing power to your car’s electronic components such as the radio, headlights, internal lighting, air conditioner, and power windows kit among others. However, when you fire up the engine, the alternator takes over the role of powering these electronic components. But other than that, the alternator is responsible for recharging the battery.

So, in case the charging system is not working, then it means the battery will have no power to ignite the engine once you turn off the vehicle.


  1. Defective Alternator

In our previous point, the issue was caused by a faulty charging system. At this point, we’ll be discussing a faulty alternator diode. Just as we’ve mentioned earlier, the alternator is designed to perform two major tasks—to power your car’s electronics and to recharge the battery.

Now, there are times when the alternator diode can get faulty following extreme corrosion. This causes the circuit to draw excess power from the battery when the engine is off causing it to drain its resources faster than usual.


  1. Extreme Temperature

Extreme temperature is one of the factors that can cause your battery to struggle. If temperatures are extremely cold (below 10°F) or hot above 100°F, then this can cause your battery to suffer. In most cases, sulfate crystals tend to build up in the battery causing it to lose its ability to hold a charge.

Thankfully, most battery manufacturers are making specialized batteries that can handle extreme temperatures. So, if you live in regions where such temperatures are typical, then you might wish to invest in such batteries.


  1. Excessive Short Drives

Now, this factor is directly related to the alternator. However, we’re not dealing with a faulty alternator here, but rather “bad driving habits”. You see, one function of the alternator is to charge the battery. But, for it to do that, you have to drive for long distances to give it ample time to accomplish its work.

If you’re the type of person that drives for just 10 to 15 minutes, then what you’re doing is that you’re denying the alternator enough time to charge the battery. If the battery is not sufficiently charged, then the car’s dashboard clock and the alarm system will drain the remaining juice leaving you with a dead battery.


  1. Loose or Corroded Battery Terminals

Loose or corroded battery connection is something that happens often especially if your car is not well maintained. Your car’s battery cables perform two major tasks. They allow the battery to provide power to the car’s electrical components (when the engine is off) and also allow the battery to get charged by the alternator when you’re driving.

So, if there’s a loose connection, probably due to vibrations and bumping, or signs of corrosion, caused by sulfate crystals, then the battery might struggle to transmit power. Thankfully, this issue can be handled easily by just checking for signs of corrosion.


  1. Parasitic Drain

A parasitic drain is a situation where your car’s electronic components continue to consume power even after the engine is off. This condition is normal, as the battery has to provide power to your car’s security system, radio presets, and clock. After all, this is what keeps your vehicle secure when you’re not around.

However, there are times when the battery can exceed its usual drain. This excess drain can be caused by faulty wiring, defective fuses, or failing electrical systems. If this problem is undetected, then it can drain your battery overnight leaving you with an empty cell.


Final Verdict

So, have you been carrying your jumper cables every time you start the engine? Well, I guess it’s time to put them aside as this guide has discussed eight possible reasons that can cause your battery to drain. Just as we mentioned at the beginning of this guide, a battery drain can occur due to three major reasons. These are driver’s error, electrical system problems, and battery problems.

So, to solve this issue, start by inspecting the battery while reducing driver’s error as much as possible. If the problem persists, then it means the possible cause is an electrical problem, which in this case will require a professional mechanic.

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