How to Change Your Car Battery: Step-By-Step Guide

Mark Linsdell
Mark Linsdell5 min read
How to Change Your Car Battery: Step-By-Step Guide

If you’re a car owner, it’s highly likely you’ll need a battery replacement or two during your car’s lifetime.

Unfortunately, a lot of us are still unsure of how to switch out and replace our own car batteries. Thankfully, it’s a relatively easy fix. To help guide you through, we’ve put this step-by-step guide together.

A car battery replacement is just routine car maintenance. However, if you’d rather relax and not worry about replacing it yourself, we’ll also tell you the best place to get it fixed.

How can you tell if your car battery needs replacing?

There are a number of telltale signs that your car battery is out of juice. However, these are the most common:

  • Car won’t start

  • Car won’t start after being jump-started

  • Battery warning light on the dashboard

  • Check engine warning light on dashboard is flashing

  • A lot of powdery residue on the battery

If you notice any of these, it might be time to get your battery replaced.

How long do car batteries last?

The answer to how long a car battery lasts for differs depending on who you ask. For instance, some cars can go five to six years without a battery replacement. Whereas, some will need a new one every one or two years. Therefore, it’s best if you split the difference. The average car will need a battery replacement every three to four years.

However, there are several things that will shorten your car’s battery life and see you having to bump forward a battery replacement:

  • Inactivity - Rarely using your car or only using it for short 10-to-15-minute commutes will weaken your car battery. Why not mix it up by taking the scenic route to work or taking the road trip you’ve always talked about?

  • Leaving the power on - Leaving the power on while the ignition is off is a bad driving habit and bad for your battery. What’s more, if you leave the interior light on overnight or leave the key in the ignition, that’s a surefire recipe for a dead battery.

  • Climate - If you live in a particularly hot part of the country - like the FixMyCar team in Houston - then your battery won’t last as long as it would in colder climates. This is not something you can help but it’s something to be wary of.

How to change a car battery

Now you have an idea of how long your car battery will last, it’s a good idea to know how you can change it yourself. We got you.

Before we get into the steps, you’ll need to get these items to make the switch:

  • An adjustable wrench

  • Clean lint-free rags

  • Baking soda

  • Water

  • Disposable rubber gloves

  • A battery brush or equivalent post cleaning tool

  • Safety goggles

And, to make sure you’re doing this change safely, turn off your engine, put your car in park, and set the parking brake. After that, spread a towel across your fender. This’ll protect the car body’s paint from any corrosive acid. Furthermore, to ensure you’re not missing anything, consult your own car’s manual as well.

Now we’ve got the precautions out of the way, let’s get into the steps required to replace a car battery.

Step 1: Remove cables from battery terminals

First off, you want to remove cables from battery terminals. Before you do this, you need to identify whether your car has a negative ground or a positive ground and the correct order for removing battery cables. Your car manual will tell you this information.

If your car has a negative ground, loosen the nut and bolt that holds the battery cable clamp to the negative terminal. This is usually labeled with a minus sign or ‘NEG’. Whereas, for positive ground, you loosen the positive cable first. This is usually labeled with a plus sign or ‘POS’.

Step 2: Remove the screws or fasteners holding the battery and then remove it

When doing this step, it’s vital you put the screws or fasteners in a safe place. You’ll need them later!

And, when removing the battery, make sure you wear disposable rubber gloves.

Step 3: Inspect and clean the tray

The old battery may have left rust or have other corrosive debris in the tray. However, this is an easy fix. Simply dissolve a little bit of baking soda in some water and use this solution to clean out the tray.

Make sure you leave your gloves on for this and also use the time to give your battery terminals a clean.

Step 4: Position your new car battery

Next up, you need to position your new car battery on the tray. This is relatively straightforward.

However, you still need to double-check that it’s facing the same direction as the old battery and is seated firmly and securely.

Step 5: Reattach the screws and fasteners

Now, you need to screw back in the battery screws and fasteners you set aside earlier. This will secure the battery is in place and ensure there’s no wiggle room.

Step 6: Reconnect the battery cables in the reverse order you removed them

Pretty self-explanatory, but make sure you reconnect and reattached the battery cables in the opposite order you removed them.

So, if the negative ground was disconnected first, make sure you reattach the positive first. And vice versa.

Step 7: Dispose of your old battery

Car batteries are toxic and corrosive. Therefore, they need to be disposed of responsibly and legally.

Special recycling centers will accept old batteries and charge you a nominal amount to dispose of them for you. You find a place to recycle your car battery here.

Where to get a car battery replaced?

As you can see, carrying out a car battery replacement at home is relatively straightforward. However, if you have any concerns about the corrosiveness or weight of your car battery, it’s best to get it replaced by a professional.

Previously, your best bet was taking your car in for a battery replacement at a repair shop. However, in 2021, this has some clear disadvantages:

  1. It’s expensive - If a repair shop senses you as a car novice, you could be taken advantage of. Before you know it, your invoice includes additional fees and you’ve been upsold on frivolous extras you don’t need.

  2. It’s inconvenient - You have to go to a physical auto repair shop. This is difficult usually, but even more so with a spluttering battery.

  3. Rigid hours - Repair shops have limited hours. For some of us, our cars are like another limb. Therefore, we need to get our battery replaced as soon as possible.

Luckily, FixMyCar is here to help. First off, we’re around 30% cheaper than repair shops and have fixed and upfront pricing. We’re also open from 9 am-9 pm, seven days a week and, most importantly, we’ll come to you.

Get a quote from one of our certified and experienced technicians and get your car battery replaced now

Bottom line

We hope you now have a clear idea of how to replace your car battery. While the time required between battery changes depends on the model of your vehicle, it’s important you don’t leave this replacement slide.

Be sure you consult your car’s manual and, if you have any concerns about replacing it yourself, get in touch with FixMyCar for a mobile car battery replacement.


We understand how frustrating it can be when your car breaks down. That's why we're here to make sure you can get back on the road in no time without any hassles. Our certified mechanics come with all the necessary tools and equipment required for repair and maintenance work -  saving you time, money and effort.