Sooner or later, you’ll need to change your car battery. Even if you’ve managed to eke a little more life out of it with an auto battery charger, you can only put off the inevitable for so long. Finding the best replacement is important, but knowing how to remove your old battery is also key. Proper battery removal ensures your safety and keeps your vehicle’s electrical systems intact. This short guide tells you what you need to know about disconnecting your battery.
How To Disconnect a Car Battery
Disconnecting a car battery is fairly easy, but following the proper order is critical for a safe disconnection. First things first – your vehicle should be off. Your battery cables are attached to the terminals by a nut, so you’ll need to use a socket or adjustable wrench to loosen each nut. You should always remove the NEGATIVE terminal cable first. Then after unhooking the negative terminal and setting it aside, disconnect the positive terminal.
Why is this so important? Think of it this way: Your vehicle’s electrical system is a closed circuit. The negative terminal’s cable connects to your vehicle’s frame, which is part of the circuit, but its current flows from your car’s frame and components. Positive current, on the other hand, flows into the circuit from your battery.
If you disconnect the positive cable first, there’s always a chance that you may accidentally touch it to other metal pieces. This completes the circuit but can cause a short in your car’s electrical system. Even if your old battery has just a small amount of juice, you could blow fuses or generate sparks that ignite and explode your battery. Any of these can result in serious injuries.
Safety Tips for Disconnecting the Battery
So, now you know: negative terminal first, then positive. But that’s not the only important safety tip when disconnecting a battery. Besides your wrench and socket tools, you need other important supplies:
- Safety gloves
- Eye protection
- Zip ties for cabling
- Shop towels
The need for safety gloves and eye protection is obvious – you could come in contact with battery acid, which is highly corrosive and can result in serious burns. But what about the zip ties and towels? Zip ties contain no metal, so they’re safer for keeping loose cabling out of the way. Placing a towel over the positive terminal keeps it from coming in contact with other metals.
Once you’ve disconnected the battery cables, you’re still not quite done. You must also disconnect the brackets holding your battery in place. In most cases, you just need to unscrew them. Next, lift the battery carefully out of your vehicle and set it aside.
Finding Your Replacement
Most batteries’ lifespans range between two and five years, but that can vary with each driver’s habits. Before you’re left dead in the water, it’s a good idea to monitor your battery’s health. Many auto parts retailers offer free battery testing. When you’re shopping for your replacement, use a free VIN lookup to find models that fit your vehicle by its exact make, model and year.