Replace a Car Battery

Remove the negative (-) battery terminal wire first with a wrench.

Your car’s battery is a storage container that gathers electrical power (produced by the engine) and stores it for use by lights, motors, relays, and other gadgets. So it’s important that the battery hold the charge.

Fortunately, modern sealed or maintenance-free batteries don’t need much service. Other than periodically checking the battery connection, there’s little to do except wait for the day it should be replaced. Typically that’s every 3 to 5 years. You can replace a car battery in just a few minutes.

Fix-It Tip

Many new cars have a security code that must be re-entered into the radio if it is disconnected from the car’s battery (as in a theft) or if the battery itself is disconnected. The owner’s manual will tell you if this is true for your car and what to do about it. Typically it means making sure you have the security code before you disconnect the battery and re-entering it when you’re done.

Here’s how to replace a car battery. You can do it yourself:

1. Find the car’s battery; it’s usually under the hood on passenger’s side of the car, but could be just about anywhere.

Clean the terminal with a battery terminal cleaner brush.

2. Disconnect the cable from the negative (-) side of the battery first, then the positive (+) side. Use a battery brush to clean the terminals.

3. Remove the hold-down frame that keeps the battery in place.

4. Attach a battery carrying strap (from an auto parts store) to the two terminals and carefully lift the battery out and away from the car.

5. Inspect the battery holder or tray for corrosion and damage. If needed, clean the area with baking soda and water or a similar cleaner (also from your auto parts store) before installing the new battery. Make sure cleaners or water don’t damage nearby electronic equipment. If the battery cables are damaged, replace them as well.

6. Use the battery strap to reinstall the new battery, then reinstall the hold-down frame.

Clean the terminal wire with a battery terminal cleaner brush with the cap removed.

7. Attach the positive cable, then the negative cable to the corresponding battery terminals. Note: Battery terminal rings and lubricants can be used to help neutralize corrosion before it builds up. Your auto parts store has them.

Fix-It Tip

Battery terminal rings and lubricants can be used to help neutralize corrosion before it builds up. Your auto parts store has them.