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Maintaining Power: How to Check Your Car Battery

Machine battery

It goes without saying that your car battery is one of the most crucial elements that keeps your car going, day in and day out. However, it's also one of those elements that is so easily overlooked -- out of sight, out of mind, right? 

Only when your car starts to play up does the health and car battery life of your vehicle come to mind. But by then, it could be too late and your battery might need to be replaced. 

Regular battery checkups and testing can help you keep your car's heartbeat strong. We've put together this blog to help you recognize the top car battery warning signs and how to test a car battery yourself, so read on for more... 

How Does a Car Battery Operate?

First thing's first, you want to understand exactly how your car battery works, before you learn how to maintain it. There is a myriad of functions that simultaneously take place as soon as you fire up the ignition. But when it comes to your car battery, it will start to lose voltage right away. 

This is because your car battery focuses most of its energy on switching on the starter motor. Once your vehicle is idling, the alternator kicks in to charge the battery. Basically, your car battery drains each time you start and drive your vehicle -- this is why your vehicle's alternator is so important.

Other than firing up the starter motor, your battery also powers other crucial functions. Such as, powering the ring gear on the flywheel, which helps to turn the engine at speed. This allows fuel and air to pump into the engine cylinders, ultimately powering your vehicle. 

So, what is the average life span of a car battery? For most vehicles, it's between 4-6 years. However, the average car battery life varies based on a number of factors. This includes weather conditions, vehicle age and type, and how you drive your car.

A great way to extend your car battery lifespan is with regular maintenance and testing.

The Top Signs That Your Car Battery Is Failing 

All is well in the world until you begin to notice a few niggly issues with your car. While it could be any number of general car maintenance problems, it's always wise to check out the health of your car battery, first. Here's how to tell if your car battery is bad or it's time for car battery replacement:

1. Consider the Age of Your Battery

No matter whether your car is brand new or second-hand, you should have a rough idea of how old the battery is. If it exceeds 6-7 years, your auto battery life is most likely to take a dive.  

However, the rate at which it performs is dependent on a number of variables, as mentioned. Some car batteries can last for a decade without any major issues. This is why it's wise to know the obvious signs of when to replace a car battery. 

2. How Often Your Car Is Used 

You might have heard that idle cars depreciate far faster than cars that are driven often. This has to do with the battery life of a car. The less you drive your car, the more your battery is likely to fail. This is because your battery charges each time you drive it, as we outlined earlier.

So, if your car is sitting around, unused for long periods of time, this can affect the health and lifespan of your car. You may be wondering, how long does a car battery last without driving? The average time is just 2-3 weeks! 

Bear in mind that battery function can also affect fuel economy and many other aspects of your vehicle's health. 

3. A Delay in Engine Start 

When you start your car, your engine should fire up right away. The longer your car takes to start means that it's the right time to change a car battery, or check it out at least. 

Some other weak car battery symptoms to look out for include:

  • An illuminated battery light on your dashboard that doesn't turn off
  • Your headlights are dimmer than usual -- this is because your battery is low on power and cannot run electrical functions
  • Your engine cranks very slowly when you turn the ignition
  • You may need to pump the gas (accelerator pedal) in order to get your car started
  • There is a clicking sound coming from the engine area, followed by stalling power or none at all

If you find your car battery overheating easily, this is another sign that something is wrong. If you're a novice when it comes to cars and how to change a car battery, you want to take it to an experienced mechanic right away. 

Do It Yourself: How to Test a Car Battery 

Before you take your car to a professional, there are a few simple ways you can test your car battery yourself. You want to be 100 percent sure that replacement is necessary and there's definitely an issue with the battery, and not some other component. 

You'll need to know how to load test a car battery which is usually done with a multimeter voltage reader. 

How Does a Multimeter Work?

The overall premise of a multimeter is to indicate how much voltage your car battery stores. The voltage is what powers your battery. With enough voltage, your car should run without any issues. 

You can find voltage multimeters just about anywhere, including on Amazon for under $10 in order to run a simple voltage test at home. Once you've invested in a multimeter, you can regularly test your car battery and avoid major car issues down-the-line. 

How to Test Car Battery Amps With a Multimeter

Car battery with wires
Car battery

Before you test out your car battery, you want to make sure your car engine is turned off and has been standing for about one hour. You don't want your multimeter to pick up any of the battery discharges right after your engine has been in use. 

If you can leave your car to stand overnight, that's even better.

It's never a good idea to test your car battery while your car is running. This is because the multimeter will pick up the power charge from the alternator, and not the battery. Basically, this isn't an accurate reading of what's really going in your car battery. 

Step One: Inspect the Battery

If you've never inspected a car battery before, you'll find it under the hood of your car, on either the right or left side of the engine. Depending on the make of your car, the battery may be located in your trunk. 

Most car batteries have a plastic cover to protect the battery house. This can be removed without tools, but in some cases, you may need to remove a few bolts or screws. Once you've removed the battery cover, keep all metal tools away from the battery.

Step Two: Prepare Your Multimeter

In order to accurately test your car battery, you must set your multimeter to the correct range. The ideal setting is at 20 DC voltage. This allows you to test a car battery that stores anything from 0-20 volts. 

Turn the knob on the multimeter to ''20'' on the ''DCV'' range -- this is the direct current voltage. Once you've done that, the multimeter should display a reading of 0.00. 

Step Three: Connect up the Components 

For this step, you'll need to connect your multimeter with your battery. Connect the red meter probe -- also marked as ''+'', with the red/positive battery terminal. Do the same thing with the black meter probe, and the black battery terminal. 

You should have your reading within a few seconds. Most car batteries that are healthy and fully-charged will show a reading of 12.6 volts or more. If your car battery reading is 12.2 or below, this means the battery is only charged to 50 percent. 

Anything below 12 is a very low reading and is one of the top signs your car battery is dying. In some cases, your battery may need an overnight charge and then you can re-test it again.  

Step Four: Test the Battery Function 

Now that you know the voltage stored inside your battery, you should also test how your battery functions when it's in use. You'll need another person to assist you with this step. Ask them to start up the engine while the multimeter is still attached to the battery. 

Ideally, your battery voltage should not dip below 10. If it goes below 5, then this is an indication that your battery is old, tired, and needs to be replaced. With a voltage of 10 or below, your battery will struggle to fire up the starter motor, let alone anything else. 

Looking to Upgrade Your Car, the Fool-Proof Way? 

Sometimes, simple car battery installation just isn't enough to revive an old vehicle that needs to be let go. If you're thinking of selling your old car, or trading it in for a new one, allow VINinspect to help you find the best quality on the market.

We provide thorough and accurate vehicle history reports so that you know exactly what you're buying into before you make the financial commitment.

Once you have your new set of wheels, you can keep it in top condition with this helpful information on how to test a car battery and the signs to look out for when it needs a little TLC. Get in touch with our team and learn more about how we can help!

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