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Why Battery Light Is On But Alternator Is Charging and What to Do?

Your car battery or charging light on the dashboard of your car indicates a malfunction in the battery circuits or bad charging of the car battery. The light provides you with a warning when the charging system is not charging the battery with the right voltage. However, the warning happens due to many reasons, so it is vital to take the proper steps to know the actual issue before trying to replace any components. One of the problems, which many car drivers face, is when the battery light on but alternator is charging.

Why Battery Light On But Alternator Is Charging

In case the battery light stays on when you start the car, do not worry. It is usual for the light to power on when you turn the ignition to your vehicle. Usually, the light turns off after some time, but if it stays on even when you are driving, then pay attention.

You might notice some signs of a weak battery, including power windows not coming up, or the audio system not working. Let’s perform a few checks to see where the problem lies.

Check for Corrosion

In some car models, the fumes from the regular functions lead to corrosion to collect on the battery terminals. It happens particularly during summer or during warm weather. We recommend you instead remove the covers from the terminals located on top of the car battery.

The presence of a white or greenish substance on the top of the battery or near the terminals is a clear case of corrosion. The corrosion can interrupt the conduction of electricity from the array to the car. Remember not to touch the corrosion with bare hands, as it can lead to skin irritation. It is the first step to help you resolve battery light on but alternator is charging issue.

battery light on but alternator is charging battery corrosion
It is recommended not to touch the corroded terminals with bare hands

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Clean the Car Battery Terminals

If you notice some corrosion or grime around the battery terminals, it might be the reason why the car battery light is still on. A significant advantage is that it is easy to clean the battery terminals using standard grease. What you need to do is remove the battery terminals, remove the battery cables, and clean the battery terminals.

Tighten the Battery Clamps

At times, the battery light remains on due to a weak connection between the car battery and the cables that connect to it. Ensure the clamps fastened to the battery terminals. In case you notice the clamps are loose, then use a small wrench to tighten them until they completely cover the terminals.

Corrosion on the terminals makes the warning light to blink
A white or greenish mater forms on the battery terminals as corrosion

The car battery is a vital component that provides the vehicle with the necessary power to run on the road. Apart from the issue of battery light on but alternator is charging, you might encounter quite a number of problems with your battery or your alternator that is causing your car slow to start. Refer to these ultimate guides How To Test A Car Battery With A Multimeter and How to Test an Alternator: The Complete Guide to familiarize yourself, which you must, with these critical components in your vehicle.