How to Disconnect and Connect a Car Battery Safely and Easily
The 12-volt battery in your vehicle is essential, whether you drive a gas-powered or electric car. When that battery starts to go bad, getting a new one can help keep you from getting stranded. Removing the old and connecting a new battery to your car can require special care, equipment, and step-by-step directions to get it done right, including which terminal to disconnect first. Here’s what you need to know about replacing a car battery and how to avoid damaging the electronics, transmission, and engine in your vehicle when you do it.
Les Schwab has been installing new batteries for decades. If you drive a newer vehicle with a lot of electronics, stop by any location and have your new battery installed correctly.
Before You Get Started: Consider These
Safety
Batteries are filled with corrosive materials that can cause considerable damage to people and property. When Les Schwab professionals remove and install batteries, they often wear eye and face protection, as well as gloves. If a battery is leaking, our professionals will also wear protective aprons. Following these same safety guidelines can help protect you as well.
Battery Type
The type of battery you need depends on what you drive. Refer to your owner’s manual for the battery size or group, battery type, as well as the minimum cold cranking amps required for your car or truck. Getting the wrong battery can cause power issues, including stalling your engine and shutting off safety features. The professionals at Les Schwab can show you all of your battery options and help you make the right choice.
Tools and Equipment
Besides safety equipment, you’ll need a wrench to disconnect the terminals, as well as a towel to protect the side of your vehicle from damage. Need help with your battery? Les Schwab has the tools and equipment to get yours done right.
Your Owner’s Manual
Inside your owner’s manual, you’ll find detailed information about the proper steps to remove and replace your car battery. If those directions require a battery saver as well as initializing your electronics once the installation is complete, bring your vehicle to Les Schwab. We have all the right tools and the know-how to get it done right. Removing or installing a battery incorrectly can result in the loss of your entertainment system presets, air-conditioning functionality, and ADAS (Advanced Driver Assistance Systems). It can also affect your transmission and engine.
How to Correctly Disconnect a Car Battery
1. Turn Off the Engine
Once the engine is off, remove the key and place it at least 15 feet from the vehicle. If your vehicle has a proximity key that detects your vehicle, this will keep it from talking to your car’s computer during installation.
2. Wait 10 Minutes
This gives your car’s computer enough time to properly shut down. Disconnecting the battery before that computer is off could damage your vehicle’s computer system.
3. Connect a Memory Saver
These devices connect to your car’s OBDII port, often found under the dash behind the steering wheel. This is the same port used to diagnose a car or check its emissions. Without a battery saver installed, you could experience voltage spikes, which could damage your power windows, disable safety features, and cause your transmission or engine to function improperly.
Les Schwab uses a memory saver on every vehicle that requires it.
4. Locate the Battery and Terminals
Once you’ve located the battery in the engine compartment, under the back seat, under the passenger seat, or in another location, look for the black negative (-) and red positive (+) terminals. Still not sure which terminal is which? If the + and – symbols are not legible and the positive cable is not covered in a red hood, there is another way to possibly spot the two different terminals. The positive post often has a bigger diameter than the negative post. However, be sure before disconnecting or reconnecting any posts on your vehicle.
5. Disconnect the Negative Terminal
Start by disconnecting the negative (-) terminal. This might require a wrench. Set the cable aside on a towel or place it inside a tennis ball with a slit added to one side. This will ensure the cables don’t touch metal and cause issues.
6. Disconnect the Positive Terminal
Using a wrench, disconnect the positive terminal. Place that cable on a towel or inside a tennis ball as well.
7. Loosen and Remove the Battery Hold-Down
Most vehicles will have a battery hold-down or bracket system to keep the battery in place while driving. Loosen the fasteners and remove the hold-down from atop the battery.
8. Remove the Car Battery
A battery can weigh upwards of 40 pounds, so lift carefully. Always lift the car battery straight out of the compartment. If you need a second person to help, be sure they also wear protective equipment.
Does your battery simply need to be charged up? Les Schwab does it for free with your Les Schwab battery warranty.
How to Connect a Car Battery Correctly
1. Inspect and Clean the Terminals
Over time, corrosion can build up on a battery and your vehicle’s terminals. With the old battery out, clean the terminals to avoid adding corrosion to the new battery and reducing its overall lifespan.
2. Install the Battery
Carefully place the new battery into the battery box and reinstall the hold-down.
3. Reconnect the Terminals
First, connect the red or positive (+) terminal. While that is being installed, leave the black or negative (-) cable safely in the towel or tennis ball. Once the positive is installed, attach the negative cable.
4. Tighten the Bolts
Using a wrench, ensure both the positive and negative cables are secure and tight. Do not touch your wrench to any metal in your vehicle while tightening the bolts to avoid damaging the battery or your vehicle.
5. Register the Battery and Your Electronics
Using the OBDII port and a special battery registration device, you can now register your new battery. This helps ensure the computer systems in your vehicle do not overcharge the new battery, which can damage it and the electronics in your vehicle. Additionally, registration allows you to reset the electronics in your vehicle, including the windows, sunroof, remote locks, and seat presets, as well as ADAS and other safety systems.
The professionals at Les Schwab have the tools to register your battery and reset the electronics in your vehicle. Book your appointment now.
6. Test the Battery
Once the battery is installed properly and registered, it’s time to give it a test. As long as your car starts and everything works as expected, the battery has passed.
Don’t like to take chances with your battery? Get to Les Schwab. We’ll remove your old battery, install the new one, and send you home with a Les Schwab Battery Warranty.
Trust Les Schwab for Your Battery Needs
All of your battery answers and expert installation are at Les Schwab. When you buy your battery from us, you’ll get free battery checks and free charging services when you need them — all at no extra cost.