How to Change a Car Battery: 12 Steps

Table of contents:

How to Change a Car Battery: 12 Steps
How to Change a Car Battery: 12 Steps

Automotive batteries don't last forever, even with proper care. If you notice your headlights dimming, if you need to jump start your car due to a dead battery, or if the battery is more than 3 years old, it is time for you to replace it. Fortunately, this is a quick and easy project that you can tackle at home with just a few basic tools.


Part 1 of 2: Remove the old battery

Step 1. Park on a level surface in a safe area and turn off your vehicle

Avoid changing the battery on the side of the road whenever possible. Find a safe place to work away from traffic, open flames, sparks, or water. Activate the parking brake and turn off your vehicle. Take the keys out of the ignition to make sure the battery is not receiving electricity.

The garage or driveway are good places to change the battery. Just make sure the area is well ventilated (that is, keep the garage door open)


Clock, radio, navigation system, and alarm settings will be reset when the battery is disconnected, so make sure you know the alarm code before starting. If you don't remember, you can consult your owner's manual.

Change a Car Battery Step 5
Change a Car Battery Step 5

Step 2. Put on your safety gear and open the hood

Batteries contain an electrolyte solution of sulfuric acid, which is highly corrosive, can burn your skin, and produces flammable hydrogen gas. Wear thermally insulated work gloves and safety glasses to protect yourself. Then open the hood and support it on a pole, if necessary.

  • Remove any metallic jewelry you are wearing (such as a watch or ring) to protect yourself from possible electrical shock.
  • Wear old clothes that you don't mind getting grease on.
Change a Car Battery Step 6
Change a Car Battery Step 6

Step 3. Locate the battery

Look for the battery in a corner of the engine compartment, either near the windshield or the front bumper on both sides of the car. Find the rectangular battery box that has 2 cables attached. If you have a newer car, the battery could be located under a plastic cover, which you will need to remove if necessary.

  • Check your owner's manual if you can't find the battery.
  • Note that in some vehicles, the battery is located in the trunk rather than under the hood.
Change a Car Battery Step 8
Change a Car Battery Step 8

Step 4. Disconnect the negative cable first and secure it with a zip tie

You should always remove the negative cable before the positive cable to avoid a short circuit. The negative battery terminal is usually black and may have a minus sign (-) nearby. Remove the plastic cover, if applicable. Next, loosen the clamp on the negative cable with a wrench and slide the cable out of the terminal.

  • Use a zip tie to secure the negative cable to the engine compartment, making sure it doesn't come in contact with anything metallic.
  • Depending on the vehicle, you may need a 7, 8, 10 or 13mm wrench to remove the cables. However, if the battery terminals have quick-release clamps, you won't need any tools to remove the cables.
Change a Car Battery Step 9
Change a Car Battery Step 9

Step 5. Disconnect the positive cable and secure it with a zip tie

The positive terminal is usually red and may be marked with a plus sign (+). Remove the plastic cover over the terminal if your vehicle has one. Then, use a wrench to loosen the positive cable clamp and remove the cable from the terminal. Secure the cable to the engine compartment with a clamp.


Make sure the positive and negative wires are not touching each other and do not let them touch anything metallic, as this can cause a dangerous short circuit.

Change a Car Battery Step 10
Change a Car Battery Step 10

Step 6. Remove the battery from the vehicle

Inspect the bracket that secures the battery in place and remove all the connectors that hold the battery to the bracket. You will likely need a socket wrench, a socket wrench of the correct size, and an extension bar. Once you have removed all the fasteners, you should lift the battery out of the engine compartment and set it aside on a concrete surface (if possible).

The battery is likely to weigh more than 20 pounds (10 kg), so ask a friend for help if you can't lift it yourself

Part 2 of 2: Install the new battery

Step 1. Clean the battery terminals to remove corrosion

Check the terminals for a build-up of green, blue, gray, or white dust. Use emery cloth or 100-grit sandpaper to carefully clean the corrosion from the terminals until they are shiny.

Remember that battery acid is corrosive, so you should avoid splashing it on your skin or clothing

Change a Car Battery Step 2
Change a Car Battery Step 2

Step 2. Purchase the correct replacement for the battery

Take a picture or write down any information about the old battery (such as size, dimensions, and part number). Go to an auto parts store and provide an employee with this information, as well as the year, make, model, and size of your vehicle's engine. In this way, you will be able to find the appropriate replacement.

  • Automotive batteries vary in size and electrical capacity, so be sure to buy one designed for your specific vehicle.
  • If you live in the United States, you may want to take your old battery with you. Some auto parts stores allow you to change the old battery so you don't have to pay a "base fee" for the new one.
  • If the auto parts store doesn't remove the old battery, you can take it to a service center or recycling center for disposal. Do not simply dispose of it as it contains corrosive material.
Change a Car Battery Step 12
Change a Car Battery Step 12

Step 3. Secure the new battery to the bracket and lubricate the terminals

Place the new battery in the appropriate tray and secure it to the holder. You simply have to reverse the process you used to remove the battery from the holder. Then cover each of the terminals with a thin layer of lithium grease to prevent corrosion.

  • Make sure the battery is oriented the same way as above.
  • Verify that all the fasteners on the mount are secure so that the battery does not vibrate or move while you drive.
  • Avoid spraying lithium grease on any part of the engine block other than the positive and negative terminals.
Change a Car Battery Step 13
Change a Car Battery Step 13

Step 4. Reconnect the positive cable first

Untie the tie that secures the positive cable to the engine compartment, taking care that the end does not touch anything metallic. Lay the wire over the terminal and use a wrench to tighten it. Place the cover over the terminal, if your battery has one.


When reconnecting the battery, you should always secure the positive terminal before the negative so that you do not inadvertently complete the electrical circuit before everything is connected.

Change a Car Battery Step 14
Change a Car Battery Step 14

Step 5. Reconnect the negative cable

You must repeat the process to untie the tie and reconnect the negative cable to the negative terminal. Tighten the clamp with a wrench and make sure that neither the wrench nor the negative cable comes in contact with anything metallic, as this could cause a dangerous electric shock.

If the battery has a plastic cover, you can replace it at this time

Change a Car Battery Step 16
Change a Car Battery Step 16

Step 6. Close the hood and start your vehicle

Make sure to remove all the tools under the hood and then close the hood. If you've done everything correctly, and the battery really was the cause of the power issues, your car should start right away. If necessary, you can enter the alarm code.

Make sure all your electronic devices are working properly. Then reset the clock, radio, and navigation system


  • Wear old clothes that you don't mind spoiling.
  • Some batteries are in the trunk rather than under the hood.
  • Some large vehicles have more than one battery, sometimes in different locations.


  • Wear thermally insulated safety glasses and work gloves.
  • Remove metal jewelry before changing the battery.
  • Avoid working in wet conditions.
  • Do not place an automotive battery on its side or upside down.
  • Never connect the 2 battery terminals directly.
  • Do not leave metal objects on the battery, as the 2 terminals can connect and form a circuit.

Popular by topic