Everything You Need to Know About Car Batteries

Knowledge is power when it comes to your car’s battery and electrical system. In fact, it’s your ride’s heart and soul. The last thing you want is to be left stranded with a dead battery. The more you know about your battery and electrical system, the less likely you’ll get stuck. At Firestone Complete Auto Care, we’re here to help you understand just what’s going on with your vehicle’s battery and electrical system.

On average, a battery will last 3 to 5 years, but driving habits and exposure to extreme elements can shorten the life of your car battery. At Firestone Complete Auto Care, we offer a free battery check-up with every visit to our store. This is a quick diagnostic check to estimate the temperature at which your battery may fail. It also gives you some idea how much battery life you have left. One little test tells you if your battery is good to go.

Battery Knowledge

How exactly does a car battery work?

The car battery provides the jolt of electricity necessary to power all the electrical components in your vehicle. Talk about a pretty huge responsibility. Without battery power, your car, as you’ve probably noticed, won’t start.

Let’s take a look at how that powerful little box works:

• A chemical reaction puts your car in action: Your battery converts chemical energy into the electrical energy necessary to power your car, delivering voltage to the starter.
• Keep the electric current steady: Not only does your battery provide the energy required to start your car, it’s also stabilizing the voltage (that’s the term for the energy supply) in order to keep your engine running. A lot’s riding on the battery. Call it the ‘little box that could.’

The car battery may be small, but the power it provides is huge. Test your battery now with our Virtual Battery Tester.

Find the right battery for your specific vehicle, at the right price — right now.

Symptoms & Procedures

Are there any warning signs that may indicate my battery is on the fritz?

“If I only knew sooner.” We’ve all been there before. Fortunately, there are various indications and symptoms that your battery may need replacement:

Slow engine crank: When you attempt to start the vehicle, the cranking of the engine is sluggish and takes longer than normal to start. You’d best describe it as the "rur rur rur" starting noise sound.

Check engine light: The check engine light sometimes appears when your battery power is weak. Strange system indicator lights–such as check engine and low coolant lights–could mean there’s a problem with your battery. (It could also just mean you need more coolant).

Low battery fluid level: Car batteries typically have a part of the casing that’s translucent so you can always keep an eye on your battery’s fluid level. You can also inspect it by removing the red and black caps if they are not sealed (most modern car batteries now permanently seal these parts).

Bottom line: If the fluid level is below the lead plates (energy conductor) inside, it’s time to have the battery and charging system tested. When fluid levels drop, it’s typically caused by overcharging (heat).

The swelling, bloating battery case: If your battery casing looks like it ate a very large meal, this could indicate a battery gone bad. You can blame excessive heat for causing your battery case to swell, decreasing your battery life.

Eww, there’s a stinky, rotten egg smell: You may notice a pungent, rotten egg smell (sulfur odor) around the battery. The cause: Battery leaks. Leaking also causes the corrosion around the posts (where the + and – cable connections are located.) The gunk may need to be removed or your car may not start.

Three years + battery age is considered an old timer: Your battery can last well beyond three years but, at the very least, have its current condition inspected on a yearly basis when it reaches the three year mark. Battery life cycles range from three-to-five years depending on the battery. However, driving habits, weather and frequent short trips (under 20 minutes) can drastically shorten the actual life of your car battery.

How do I determine if my battery is too old?

For one thing, you can check the four- or five-digit date code on the cover of your battery case. The first part of the code is key: look for the letter and digit. A letter is assigned to each month — you know, like A for January, B for February, and so on. The number that follows nods to the year, as in 9 for 2009 and 1 for 2011. This code tells you when the battery was shipped from the factory to our local wholesale distributor. The additional digits tell where the battery was made. Car batteries last, on average, three-to-five years. Mind you, there are also weak battery signs to watch for, like a slow engine crank of low fluid level. If your battery case is swollen or bloated, there’s a smelly rotten egg scent coming from the battery or your check engine light appears, trouble may be beyond the bend. And if it’s over three years old? Consider it time for close monitoring. That’s what we’re here for.

View All Symptoms & Procedures

Electrical Systems

Can a bad battery harm the charging system or starter?

You bet. If you have a weak ankle, you tend to overcompensate and put more weight–and stress–on the healthy ankle. Same concept with a weak battery. When you have a weak battery, your car ends up putting additional stress on healthy parts. The charging system, starter motor or starter solenoid can be affected.

These parts can malfunction because they’re drawing excessive voltage to compensate for the lack of battery power. Leave this problem unresolved, and you could wind up replacing expensive electrical parts–typically without warning.

Quick Tip: Our Electrical System Check makes sure all the necessary parts are drawing the correct voltage. We’ll know right away if there’s any weak parts that may need immediate replacement. Don’t leave your car’s power to chance, you may end up paying for it later.

How do you know if your alternator isn’t giving your battery enough electricity?

Let’s just say we’re clairvoyant.

All joking aside, let’s start with the obvious symptoms:

• The electrical system is possessed. Strange flickering lights or warning lights such as ’Check Engine’ flicker, disappear, and then reappear again. All these malfunctions usually start occurring when the car battery is nearly drained and struggling to provide power. If the alternator is faulty, your battery will no longer receive a charge and is moments away from being totally kaput.
• The Slow Crank. You’re starting your car, and it keeps turning and turning, eventually starting–or not. This could mean your alternator isn’t charging your battery properly. If you start experiencing the possessed electrical system as well, please stop in to the nearest service facility. Your car could be moments away from a dead battery and alternator.

Let’s review: All the above happens when the battery is not receiving a charge (due to a faulty alternator). Your battery will continue to drain. When it drains completely…well, we all know what happens next: curbed car. And neither you, nor us, want you to go through that.

Quick tip: The sooner we can inspect your vehicle, the less likely you’ll face every drivers’ biggest fear–a car that won’t start. Drive with peace of mind.

Learn more about your vehicle’s electrical system

Our Services

Is it true that you provide free car battery tests?

You bet. Just ask for one during any car maintenance and we’ll give your battery the ultimate performance test with our Early Detection Analyzer. In return, you’ll receive the peace of mind knowing how much life is left in your battery or whether a replacement is recommended. We’ll also provide you with ways to improve your battery life should it be in “good” working condition. Learn more about our ‘Early Detection Analyzer’.

If you’d like to get a head start, you can gauge your battery’s life now with our online Virtual Battery Tester.

• Find the right battery for your specific vehicle, at the right price — right now.

Why do so many people use Firestone Complete Auto Care for their car battery replacement?

We’ve got the skills, and we work with quality batteries. We offer a free battery check during every visit, and we determine battery health and potential failure so there’s less guesswork for you.

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The Jolt Your Ride Needs To Ride On

Powering your ride is a complex affair. But here’s a straightforward fact: you need a functioning battery to make it go. After all, without battery power, your car won’t start. Your car battery provides the zap of electricity needed to put electrical components to work. It also converts chemical energy into the electrical energy that powers your car and delivers voltage to its starter. And it stabilizes the voltage (a.k.a. energy supply) that keeps your engine running. Important, indeed.

Stop in for a complete electrical check.

Read up on our current battery deals and specials.

Test your car battery life with our Virtual Battery Tester.

Find the right battery for your exact vehicle—at the right price.

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