Unless you buy or lease a brand-new car every few years, your battery will eventually wear out and need replacement. A mechanic, or even your roadside assistance driver, can swap it out for a new one, of course, but with a little precaution, this is a job you can do yourself.
Your car’s battery provides the energy to turn your starter motor, crank the engine, and get it started. It also powers components like onboard computers, clocks, radios and alarms when the engine is off.
As your battery ages, the materials inside it deteriorate. At a certain point, it can no longer provide enough power to start your vehicle. This process can be accelerated if you live in a very hot or very cold climate. Other reasons can include leaving your headlights or interior lights on overnight, loose or corroded battery cables, low electrolyte level in the battery, or a charging system that isn't working.
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If you have a little bit of familiarity with what’s under the hood of your car, you should be able to remove your old, dead battery and replace it with a new one. You’ll need a few basic tools, as well as some basic safety equipment to protect your hands and eyes. And remember, if you don’t feel comfortable tackling this, a mechanic will be happy to handle it for you.
First, find your battery: Most cars have their batteries under the hood, in plain sight, but some may place their batteries in the trunk or under the back seat. If you’re not sure where yours is, check your owner’s manual.
Second, make sure your battery is actually dead: Just because your car won’t start, it’s not a guarantee that your battery is dead. There could be another cause, such as a problem with the charging system, the starter or something else. Before you buy a new battery, have a mechanic or auto parts store test your old one.
Buy the correct battery: You can find the correct type and rating in your owner’s manual. If you live in an extremely hot or extremely cold climate, you might want to upgrade to a better, higher output battery. Check to make sure that the positive and negative battery terminals are in the same locations on both batteries.
Wear gloves and eye protection: Batteries have sulphuric acid inside, which is something you don’t want in your eyes or on your hands. There could be sulphuric acid corrosion on the battery terminals, which is also something to avoid.
Park your car in a safe place: This should be a flat, level surface, away from traffic, flammable materials or open flames. No smoking allowed!
Have all your tools ready: Here is a list of what you’ll need to replace your worn-out battery with a new one:
Connect a memory saver if needed: This is a battery-powered gadget that provides a small amount of power and will preserve all of your radio presets and navigation memory settings, during the time that your battery is disconnected. It usually plugs into the lighter socket. You can find one at your local auto parts store.
Open the hood: Or the trunk, or remove the back seat, as the case may be. You will need unobstructed access to your dead battery.
Remove the dead battery: Follow these steps to safely get the dead battery out of your car:
Install the new battery: Follow these steps to safely place the new battery into your car:
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You will probably need to return the old battery to the place where you purchased the new one. There are two good reasons to do this. One, you probably paid a “core charge” as part of your purchase, which will be refunded when you bring the old one back. Two, your old battery is completely recyclable, so you’ll be doing a good thing for the environment.
