Your AAA Network

Proper Care Helps You Know When to Replace a Car Battery

Don’t wind up on the side of the road! Maintenance is key to knowing when to replace a car battery before it fails.

when to replace a car battery

A dead battery can put a serious crimp in your plans for the day. You either need a jumpstart from a friendly passerby or a call to AAA Roadside Assistance to get you back on the road. But there is a way to avoid that situation entirely. Rather than being surprised when that trusty battery fails, practice good car battery maintenance. Not only will this keep your battery in working condition longer, it will help you figure out when to replace a car battery rather than waiting for it to fail without warning.

Safety first

Ever had a battery leak inside of a plastic flashlight and had to toss the whole thing? It’s not pretty. Battery acid is caustic, so it’s not something you want to get in your eyes or on your hands. Before you do any kind of car battery maintenance, put on protective eyewear and a sturdy pair of gloves.

Fun Places to Visit in the Northeast

Great Road Trips in the Northeast

Download our FREE gift, Fun Places to Visit in the Northeast: 202 Road Trips from New York and Boston.

Download Now!

Clean the cables

Open the hood and take a look at your battery to see if there is any visible corrosion. It’s a sort of crusty, white coating that you’ll find around the battery terminals. This can easily be cleaned with a simple mix of one cup of water with one tablespoon of baking soda, along with a small wire brush.

Start by disconnecting the battery cables. Once the cables are disconnected, use the water and baking soda solution to clean off any corrosion. You should also clean off the battery terminals to remove any signs of corrosion there, too. The more you remove, the better it is for the health of your battery.

Once the terminals are clean, there’s one more step you should complete to keep them in good condition. Coat them with grease made for high temperatures, which will act as a protective coating and help prevent more rust and corrosion from building up over time.

You should clean your battery this way every 6-8 months. If you notice a buildup on the terminals, that’s your cue that it’s time to give them a good scrub.

when to replace a car battery

Check the electrolytes

Now that your battery is clean, remove the covers from the battery cells to expose the fill holes. The covers are different in different batteries. Sometimes it’s a single piece of plastic you simply pry off. Other times each hole has its own cover that you twist off individually. Some low-maintenance batteries may not have filler caps at all, which means that this step is one you need to skip for your battery.

If your battery does have removable fill caps, you should be able to see down inside of your battery once you’ve taken them off. The fluid in there is an acid and water mixture and it should come up just to the bottom edge of the holes. If it’s any lower, then you need to add clean, distilled water to the mix.

Be careful not to overfill. The mixture inside your battery is caustic. If it spills out it will burn your hands and take the paint right off your car. Only fill to the bottom edge of the holes.

Check the voltage

You can test the voltage with a tool called a voltmeter to know when to replace a car battery. You can also contact AAA services to locate an approved auto body shop that can help you with the job. It’s a simple check and you can even ask to have it done when you’re getting an oil change and most shops will happily do this for you.

If you want to be able to check yourself, then look into purchasing a voltmeter. They’re small enough to easily store and they’re inexpensive. They have either analog or digital readouts, but the digital meters are easier to read and give a more accurate number to determine when to replace a car battery.

To check your battery’s charge, make sure the ignition is off and all the vehicle’s lights are off. Close the car doors, too, since the lights in your car drain the battery. The readout won’t be accurate if your car is draining power in any way while you’re attempting to take a reading.

Much like jumper cables, a voltmeter has a red positive connector and a black negative connector. Connect the positive connector on the voltmeter to the battery’s positive terminal first. Next, connect the negative connector to the negative battery terminal. Now your voltmeter will display the charge.

If the number is between 12.6 and 12.4 then your battery is in good shape. If it’s 12.2 then you’re operating at about 50 percent and if it’s 12.0 then you’re way down at 25 percent Don’t wait for your battery to leave you stranded. Contact AAA services to find someplace that can help you with car battery purchase and installation.

Checking your car battery should be a part of regular car maintenance. Add it to your checklist today and save yourself the headache of a dead battery later.

Is battery maintenance on your checklist? Let us know in the comments!

To have a professional check the condition of your battery – and replace it on the spot, if necessary – click here to learn about AAA’s Mobile Battery service


Leave a Reply

You must log in to post a comment.

Enter Your Log In Credentials
Larger version of the image

Send this to a friend