Boris Feldman Explains That When the Battery Light Turns On, the Problem Is Usually in the Charging Electrical System
Have you ever had the experience of driving smoothly and suddenly the battery light comes on in your car’s dashboard? This is one of those moments when many drivers go on high alert, immediately thinking that the battery is about to completely discharge. However, contrary to what most people think, the problem is often not with the battery, but rather with the car’s electrical system.

Understanding the Battery Light Alert
Boris Feldman, automotive specialist from CNN Brazil, explains that when the battery light turns on, the issue is usually related to the charging or recharging system of the battery. “It’s paradoxical, but when the battery light comes on, it’s not the battery. It’s because something in the electrical system responsible for charging or recharging the battery is malfunctioning,” Feldman emphasizes.
In other words, the warning light indicates that the system that should keep the battery charged is having problems, and not that the battery itself is faulty. This system includes components like the alternator and the belt, which play crucial roles in generating and distributing electrical power in the vehicle.
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Possible Causes for the Battery Light Being On
There are several reasons why this alert may arise. Some of the most common causes include:
- Belt of the Alternator Broken: The alternator belt is a crucial component that drives the alternator and helps keep the battery charged. If this belt breaks, the alternator cannot function properly, and the battery stops getting recharged.
- Faulty Alternator: The alternator is like a generator that recharges the battery while the engine is running. If it fails, the battery stops charging and begins to drain quickly, activating the warning light on the dashboard.
- Faulty Relay: The relay regulates the current going to the battery. If this component fails, the battery may receive an inadequate charge, which also triggers the alert.
What to Do If the Battery Light Turns On?
Boris Feldman advises that, although the problem is not an emergency, it is important to take the car to a shop quickly for a proper diagnosis. Ignoring this alert can lead to larger complications, especially if the problem is with the alternator belt, which in many cars also drives the water pump responsible for cooling the engine. A problem with the belt can therefore affect the cooling system, which can indeed lead the engine to overheat.
“It’s not urgent, but you have to get the car to the shop quickly,” says the specialist, reinforcing that avoiding the problem can bring even more headaches.
Prevention: The Best Path
To avoid problems with the electrical system, Feldman emphasizes the importance of checking if all the dashboard lights come on before starting the engine. This can prevent unpleasant surprises if a warning light fails due to poor contact or is burned out. “A tip is: have you ever paid attention before starting the engine to see if all the lights are coming on? What if one has poor contact or burned out just when it needs to come on, because it’s a warning light, it won’t turn on,” warns the specialist.
Keeping up with preventive maintenance is the key to ensuring the safety and proper functioning of the car. Regularly checking the electrical system and the condition of the alternator belt are simple actions that can prevent bigger worries and, who knows, save a lot on emergency repairs.
The next time the battery light comes on in your dashboard, remember: the problem is probably not with the battery, but with the charging system. Stay attentive to your car’s signals and take it to a professional to ensure that everything works as well as possible. With a little care and attention, you can avoid setbacks and maintain peace of mind behind the wheel.

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