How to Replace Car Battery Yourself

Car batteries, like humans, get old and lose the ability to hold a charge gradually leading to slow-cranking engines, dim headlights and eventually just no start. If you are seeing these warning signs, getting a new battery for used cars may need to be done. With the right tools and safety precautions, you can safely and effectively change a car battery yourself.

Safety First

Before you start your car, make sure that it is parked on level ground in a safe place, away from traffic, flames or water. Then turn off the ignition, set the parking brake and remove the keys. Because car batteries have corrosive acid and release flammable hydrogen gas, wear safety gloves and goggles. As an added precaution, take off any metal jewelry that could accidentally cause electrical contact.

Removing the Old Battery

Find the battery

Start by opening the hood and locating the battery, it is rectangular and usually inside a box with two cables going to it. In some latest car modelss, the battery is in the trunk or under a plastic cover. If you aren’t sure, consult your owner’s manual.

Step 1: Disconnect the Negative Terminal

Locate the negative battery terminal, which is usually black and labeled with a negative sign (-). With a wrench, loosen the cable clamp and slide it off of the terminal. Use a cable tie to anchor the cable away from the battery to avoid accidental contact.

Step 2. Disconnect The Positive Terminal

The positive terminal's color is usually red and has a plus (+) mark. With a wrench, loosen the clamp and remove the cable. Just as with the negative terminal, you’ll want to ensure that you secure the cable away from metal surfaces.

Detach the Battery

Most batteries are held in place by a bracket or clamp. Use a wrench or socket set to detach any fasteners. With it detached, gently pull the battery out of the engine compartment. Remember that car batteries can be heavy, so don’t hesitate to get help from a car specialist.

Installing the New Battery

Clearing the Terminals and Battery Tray

Check the battery tray for signs of corrosion or debris. If the cable clamps are corroded, remove it with a battery terminal cleaner or sandpaper.

Get the Right Replacement Battery

Look it up in your owner’s manual or an online tool to make sure you’re getting a compatible battery. That means it will have the right group size, terminal orientation and cold cranking amps (CCA) for your car.

Fasten the New Battery

Place the new battery into the tray, ensuring it's facing in the same direction as the old one. Hold it in place with the bracket and fasteners.

Reconnect the Cables

Always connect the positive cable first. Slide it on to the positive terminal, spin down the screw clamp and replace the plastic cover if it has one. Then reinstall the negative lead, and make sure it fits securely. This arrangement prevents shorting the circuit inadvertently.

Add Terminal Protection

To inhibit corrosion, cover terminals with a light coat of lithium grease or battery terminal protectors. This is done to help the battery last longer.

Shut the Hood & Start the Car

Make sure all tools are taken out from underneath the hood and shut the hood of the car secure. Get in your vehicle and crank her up and check all electronics work properly. If your vehicle has a security system, enter the alarm code if needed.

Treating Batteries to Make them Last Longer and to Power Everything

To increase your battery’s longevity, lower the number of short trips, keep terminals clean and check voltage periodically. Replacing battery on new and used cars is just a matter of course, but if you face an unexpected dead battery, you might want to try using a battery charger first. Proper disposal of an old battery can be done by dropping it off at a recycling facility or bringing it to an auto parts store that does battery disposal.

Here’s how to safely and cost-effectively replace your vehicle’s battery. If you’re uncertain of any step in the process, check your owner’s manual or contact a professional.