Battery Light on in Car

Battery Light on in Car Advance Auto

Your car battery light is on. How Should You Respond to the Problem?

The “battery light on in car problem” is one that not everyone fully understands. It can be hard to understand, unless you have a degree of knowledge about how your car’s electric system works. In a perfect world, it would simply mean there's a problem with the battery, right? But of course it's not that simple. The battery light is important, though, since it indicates a problem relating to the charging system. That means the problem could range anywhere from the connection between your battery and the car, the alternator belt, or to the alternator itself.

How Your Car’s Electrical System Works

Your battery produces 12 volts - well, 12.6 V to be exact - which is used to start the vehicle and operate many electrical systems. However, the alternator is responsible for producing the electricity that keeps your battery fully charged. When your battery light comes on, it means that something is preventing the charging system from doing its job. And, therefore, you should not count on being able to drive for too much longer when that light come on. 

Fortunately, Advance Auto Parts stores offer a range of free services, including testing your battery, starter and alternator. 

What Does the Battery Light Represent?

When the computer detects any problem with your car’s electric system, or with the recharging system in particular, then you’ll run into the “battery light on” issue. With cars being so dependent on their batteries functioning properly, a system is in place that measures the voltage produced by the alternator. If the voltage is not within certain parameters, the light goes on. The most common problem in this case is a faulty or loosened alternator belt, but it might also be possible for the alternator to fail. For a short time, your car will continue to function solely on the charge left in the battery.

How Long Can the Car Keep Running with the Battery Light On?

With the battery light on, in car recommendations will suggest that you try to keep the battery from going dead for as long as possible. But how long can the car keep going in this case? Experts consider that, if your alternator is the problem, the car will keep running strictly on battery power for about half an hour, until the battery discharges completely. Depending on the charge and voltage of your battery, that value can be higher or lower.

Important Measures to Reduce the Strain on Your Battery

If you notice the battery light on, in car measures will be necessary to make sure the battery doesn’t drain too quickly. This is especially important when you’re on a longer journey and there is no way to jump start or recharge your battery any time soon. The most important thing is not to panic. Calmly check the voltmeter on your dashboard to see the charge of the battery, and whatever you do, keep the engine running for as long as possible. If your alternator isn’t the problem, then running the engine will keep your battery going longer. Also, you might not be able to start again if you stop the engine at this point. Finally, make sure you turn off any unnecessary electronics, such as your stereo or even the AC. Also, you might want to dim the dome lights and avoid using the power windows.

Possible Solutions for Your Car

If the battery cables are loose or corroded then the problem might be obvious, as well as easy to fix. However, if there is no simple reason and no quick fix, then you might have to take your car to a repair shop to have your alternator tested. The problem might simply have to do with the alternator belt, which might loosen up or simply break after some years of use. Since all newer vehicles use a serpentine belt to power all accessories under the hood, be sure to check the tensioner for the belt (which can fail).

However, if replacing the alternator belt isn’t necessary, then your mechanic will have to check the computer for sensor readings that might indicate the real culprit. In some cases a new alternator will solve the “battery light on in car” problem, and help your vehicle’s recharging system operate normally once more.

Find an Advance Auto Parts store close to you.

Last updated July 3, 2020