How to Change a Car Battery

In this guide we’ll go over a safe and easy method of how to change a car battery. The process is virtually identical for all makes and models of vehicles unless you have a specialty hybrid or electric vehicle, at which point you would need to refer to your dealership. In order to change your car battery, you’ll want to first make sure the vehicle is off with the keys removed from the ignition. Open the bonnet and prop it up as we’ve covered in a previous guide on how to open your car bonnet. Locate your battery; it’s a large rectangular object with a red and black terminal with some heavy duty cables clamped to either side. It should be very easy to distinguish from the rest of the parts under your hood. If you can’t find it there try looking in the boot, on some models the manufacture decided to placed it there to safe space in the front.

You’ll want to start with detaching the black terminal cable from the battery. Loosen the nut that clamps the cable on with a pair of pliers or a wrench. The nut should loosen relatively easily. You don’t want to remove the nut entirely, instead, loosen it enough to where you can wiggle the wire off the terminal. If there is significant resistance and the bolt is sufficiently loose, wiggle the wire up and down to free it up. Avoid using a screwdriver or other tools to pry it off so you don’t damage anything. The cable should come off easily unless you have corrosion damage, at which point you’ll want to look into a battery terminal puller; however in most cases that’s unnecessary. Repeat this process for the red terminal and set each cable to their respective sides of the battery allowing room to perform the next step.

Next Step on How to Change a Car Battery

Locate the nut holding the clamp on to the battery. It should look similar to a belt or a strap which secures the battery in place. Once that’s loose, you should be able to lift the battery out of the tray it sits in by lifting it up and out. Car batteries tend to be fairly heavy, so lift from the bottom. Some may have a handle built in; if so use that instead. Using either battery cleaner or a mixture of baking soda and water, clean off any corrosion residue left over in the tray where the old battery was. Using a wire brush, clean off the battery connectors to free up any rust or corrosion to ensure a good connection to the new replacement.

Take the new battery and place it in the clean tray. Place the strap you previously removed back over the new battery as it was before and secure the clamp via the method you previously used to remove it, making sure it’s securely in position and doesn’t move around at all. Most new batteries come with plastic caps over the terminals; one on the red and one on the black. Remove those to expose the terminal. Next, you’ll ideally want to lightly spray each individual terminal with a coat of anti-corrosion solution. While this is an optional step, it helps your battery to last longer by avoiding corrosion buildup you’ll find on most old batteries and prolong the best connection.

Finally, you’ll want to attach the red terminal to the red battery cable first. Tighten the fastener just as you loosened it initially. Once tightened, wiggle it back and forth to check that it’s tight enough and won’t come loose during road vibrations. Repeat the whole process for the black battery cable. While you’re done at this point, it’s a good idea to go back over each step to make sure everything is snug and secure while maintaining a good connection to the terminals. If the battery cables move around, you may not have a good connection and it may not start due to a weak connection. Close the bonnet and start your vehicle. It should start up without any issues; otherwise go back and check the connections again.

Now you should know exactly how to change a car battery on your own but if you would like a more detailed explanation please carry on reading for a bullet point guild to how to change a car battery:

1. You’ll first want to ensure the vehicle is off, in park, and remove the keys from the ignition. Your battery is located in your engine compartment or boot, so pop the bonnet to begin. Prop the bonnet up using the rod in order to lock it in place while you work under the hood. Locate your battery; in most cases it will be on the right-hand side of your engine compartment. It will be large and rectangular with two thick cables coming from the battery terminals which are colour coded Red and Black. This is an important distinction which we’ll go over later in this guide.
2. First, detach the black (negative) battery cable from the battery terminal. You may need a wrench in order to loosen the bolt enough to wiggle the cable free from the terminal. Occasionally, some corrosion will prevent the cable from lifting easily from the terminal. A few gentle taps to the side of the cable after loosening the bolt should be enough to remove the cable. In some cases, major corrosion can make it very difficult to remove the cable in which case a Battery Terminal Puller is recommended and is sold at most garages.
3. Repeat the process for the Red (positive) terminal. Once both cables are free, set the cables aside. Locate the battery strap which will be clamping the battery in place. Most straps are secured with a nut and bolt, but some may require a screwdriver. Once the strap is loosened, move on to removing the battery.
4. Car batteries are typically very heavy, between 40-60 pounds, so keep this in mind when lifting the battery out. Some will have handles located on either side to assist with removal. Otherwise, lift from the bottom and place the battery safely outside of your engine compartment.
5. At this point you’ll want to clean off any residue or corrosion in the battery trap, from the hold-down strap, and the terminals of the cables. This will ensure the best possible connection to your new battery. You may use battery cleaning solution (also found at your local garage) or a simple mixture of water and baking soda. If there is heavy corrosion crusted on the cable connectors, you may need to use a wire brush or look into a battery cleaner at the shop.
6. Once everything is clean and completely dry, place the new battery in the vehicle’s battery tray. Secure your new battery in place with the hold-down strap you previous removed and ensure it’s tight and snug as you don’t want the battery moving around or shifting while you drive. This also ensures the connections are secure to prevent any power failure.
7. Optionally (but recommended) you may spray each of the new terminals with a small amount of anti corrosion solution in order to get the most out of your new battery and to prevent having to clean off corrosion early on.
8. Carefully re-attach the cables to the terminals, taking care to place the red cable on the red terminal and the black cable on the black terminal. Tighten the bolts back in place just as you removed them earlier. Do each cable in one-step; only moving on to the black cable after the red cable is completely on and tightened down properly. This will help avoid any mixups.
9. Once you’re confident everything is done, secured, and in place snugly, do a quick once-over. Try and move the battery back and forth in place to ensure the hold-down strap is on and secure.
10. Finally, put your tools away, close the hood, and start your vehicle. Your vehicle should turn on right away. If you have any issues starting your car, go back and double check the terminals and cables are connected and tight.

We hope this guide properly explained how to change a car battery so you can save some money by doing it yourself instead of paying for someone at a garage to change your car battery. Visit Car Cosmetic’s blog to find more helpful tips and guides to keeping your vehicle in tip-top shape!