ALT-1 How to Change a Battery
Changing the battery in your vehicle is usually a very easy DIY job. To figure out if you can do this on your own, determine where the battery is and take a look. Usually your owner's manual will give the location of your battery. If the battery is easy to get to, as is most often the case, and you don't have to remove anything more than a few covers, chances are you will have no problem with this task. Car batteries are usually located under the hood right in the front of the vehicle but some cars have the batteries in the trunk or under the back seat or some other strange location.
The usual indication of a bad battery is that your car is hard to start. If your car is turning over slowly, or not at all, when you try to start it you should get your battery tested. Most any auto parts store will test your battery for free before they sell you a new one. When they do this testing they can let you know if there is something else wrong with your electrical system instead of, or in addition to, the battery.
If the tests indicate you have a bad battery, go ahead and buy the replacement while you're at the store. They will probably charge you a bit extra because you don't have the old battery to exchange, due to environmental regulations, but you won't be able to pull the battery out and drive the same car to get the replacement. You'll be able to get a refund for the charge by bringing the old battery back when you are finished.
If you have two batteries in your vehicle, replace both of them. Even if the testing only indicates that one is bad it is not recommended to have any type of mismatch of batteries, whether age or type. The electrical characteristics should be identical to maximize the life of your batteries.
When you get home with your new battery, you're ready to replace it. It's a good idea to wear gloves and eye protection along with work clothing you don't care about damaging. Battery acid is extremely corrosive, not only to your skin and eyes but to your clothing as well.
When you're properly attired open your hood (or trunk, or remove the back seat, depending on where the battery is). As soon as you can get to the negative battery cable you should disconnect it to prevent a short. Sometimes you'll have to remove a cover to get to that but do it whenever you have access. Once the negative battery cable is disconnected and set to the side, go ahead and remove the positive battery cable as well. If your vehicle has two batteries remove both negative cables and then both positive cables.
Remove any covers over the battery and find the hold-downs. These may be straps over the battery or wedges on the bottom edge of the battery. The hold-downs keep the battery in place when you're driving and are an essential safety component. They are usually removed by loosening two bolts with an appropriate socket wrench. You might need an extension for this if your vehicle uses wedges, as they're usually a bit down beside the battery. Whether wedges or straps you usually don't need to completely remove the bolts. Loosening the bolts will allow the wedges to rise out of the way or straps can be removed when the bolts are loose enough by slipping hooks free from the side of the battery.
When all of the covers are out of the way, the battery cables are disconnected and the hold-downs are loose, you can lift out the old battery. Since there's a lot of lead in there be careful, car batteries are quite heavy. Most batteries are sealed but you should still try to keep the batteries upright whenever you handle them to avoid spillage of the acid inside the battery. Carefully set the old battery aside and put the new one in its place.
Reinstallation is the reverse of removal. Replace and tighten the hold-downs and reconnect the positive cables. Don't reconnect the negative cables until you absolutely have to. Make sure all of the covers you removed are securely in place and start your car.
It's as easy as that. Once you return your old battery to the store for your disposal deposit, you're all done. Since you shouldn't need to replace your batteries more than once every few years we'll hope that you don't forget how you did this the next time your car has trouble starting.
