How to Disconnect a Car Battery (7 Easy & Safe Steps)

One of the worst things to have happen while you’re driving or getting ready to go somewhere is to have your car battery die. It’s even worse if jumping it won’t bring it back to life, and you have to get a replacement.

After a trip to the shop and back, you have a new battery in hand, and as you look down at the hood of your car, it hits you. You don’t know how to disconnect the old battery, so you can replace it with your brand new on

Perhaps the battery is fine, but a new stereo is calling your name. You buy the parts and attempt to install them over the weekend, only to read that you need to disconnect your car battery before you get started to avoid injury or damage.

There are many reasons why a battery might need to be disconnected, but doing so can be dangerous if you don’t follow the proper procedure. Following these seven easy steps will have you disconnecting a car battery in no time.

Plus, the next time someone asks, you can say you work on your own car!

Things to Remember Before Disconnecting Your Car Battery

Be careful when removing.

Batteries carry electrical charges and will shock you if you’re careless. No one wants a nasty shock so wear protective gear like gloves and clothes covering your body. You’ll also want to remove any metal jewelry to avoid an unfortunate accident.

Toxic substances fill car batteries, mainly battery acid. This acid is sulfuric acid, and it’s combined with lead, another harmful material. Therefore, you should be careful when handling the car battery not to break, spill, or come into contact with any leaking materials.

Work in a well-lit and dry area. Moisture like rain and snow will increase your risk of getting shocked. Plus, it’s generally more challenging to work on a car resting at an angle.

Removing your battery may also reset your electronics. In extremely rare cases, you may need to get an electronics reset at your dealership. Be sure not to feed electricity into your car as you remove the battery to avoid shock or damage.

How to Disconnect a Car Battery – 7 Safe Steps

By following these seven easy steps, the process of swapping out a battery shouldn’t take any longer than about five minutes. So here’s the right to disconnect a car battery.

1. Turn Your Car Off

It may seem obvious, but as we mentioned before, you don’t want to send electricity through the car while you’re disconnecting the battery. Not only could it damage your electronics, but you could get a nasty jolt, as well. Instead, park your car on a level surface, engage the parking brake and turn your vehicle off.

It may also be beneficial to wait until your car has cooled down, as the extra heat may be brutal to work around, and the excess fumes are never healthy to inhale.

2. Pop the Hood

Many vehicles have the hood release lever on the driver’s side under the dash, right about where your knee would be. Pulling that lever releases the lock so you can open the hood and start working on disconnecting your battery.

Sometimes, simply pulling that level is only the first step. After you pull the lever, you may have to engage a second level under the hood, right in the middle, that finally releases the hood. If the hood isn’t on hydraulics, you’ll need to put the hood stand up to prevent it from falling.

3. Find Your Battery

Once your hood is up and out of the way, you need to locate your car’s battery. For most vehicles, it’s under the hood toward the front. But for some, it could be under a seat or even in the trunk, depending on the model.

Once you’ve found the battery, you may notice plastic covers over the terminals. The red one is for the positive terminal marked with a plus, and the negative will be black and marked with a minus. It’s crucial to remove these covers safely, as ripping them off will break the plastic locking tabs on either side.

4. Remove the Negative Terminal

The proper procedure is to remove the negative terminal first. Removing the negative terminal first avoids potential shocks or even sparks and explosions. If you have to remove the plastic cover to access the cable attached to the battery node, do so carefully to avoid breaking it.

The terminal will often be bolted tight, so you’ll need a wrench to loosen the connector. Do so carefully by using safety gear. You’ll avoid any unwanted shocks as you remove the terminal.

5. Repeat the Process for the Positive Terminal

Since the battery has a positive and a negative terminal, you’ll need to do the same process twice to disconnect the battery. This time, the terminal will be under the red cover, marked with a plus. Then, using the same wrench, loosen the cable to slip it off the battery node.

You’ll want to be extra careful with the positive terminal and not touch the cable to any metal in the car or the battery node. Doing so could damage electronic components with excess energy in the system.

6. Find and Remove Safety Bracket or Brace

Your car goes through a lot of motion when on the road. And even more, if it’s taken off the beaten path where paving isn’t a thing. Straps and brackets help to keep batteries from moving. To complete the disconnection of a car battery, you’ll need to locate this strap or bracket.

If your car has a bracket, you’ll need to use a wrench to loosen the bracket. Otherwise, a strap could be as simple as removing the velcro strapping holding the battery in place. Be sure to keep everything that came off the car; you’ll need it for the new battery.

7. Lift the Old Battery Out and Put the New One In

It would be best to put the new battery in exactly as it came out. Installing a battery backward could cause a fuse to blow. In some cases, the reverse polarity of the battery can damage your electronics or cause a fire.

The battery might be a little heavy, heavier than you would expect. Still, it makes sense with the dense materials that make up its construction. Set the old battery on some cardboard and place the new battery in the right spot.

Be sure to reattach the safety bracket and tighten each cable down to the terminal. Red on red. Black on black.

What Should I Do With the Old Battery

Proper disposal is paramount after swapping a battery. Many shops have a battery recycling program. However, it’s critical that you do not throw an old car battery away in the dumpster or your recycling bin. Not only can the battery get damaged and leak, but the material inside is terrible for people and the environment.

If, instead, you decide to get a battery from an organization such as AAA, not only do they take the old battery, but they’ll install the new one for free. Talk about an easy way to get a car repair done.

Wrapping Up…

You may find that disconnecting a car battery is necessary for various reasons. One reason could be that the battery finally died. Another could be that you’re doing some work on the electrical system and don’t want to damage anything as you work.

Regardless of why you need to disconnect a car battery, there’s a right way and a wrong way. Following these steps will keep you and your car’s electronics safe. Further, it’s essential to know where to take a battery after replacement.


Recommended Reading:

Robert Muñoz

I’m Robert, a US-based auto electrician, auto mechanic, trained engineer and fanatic about all things motor vehicle. After studying engineering in college I returned to my original passion - car mechanics - and I ran a garage for a number of years serving my local community. Through my garage, I got involved in numerous road safety campaigns in my local area until eventually, I decided to share what I've learned with the world. Know more about me... You can follow me on LinkedIn.

Leave a Comment