Battery light on: here are all the causes and how to react!

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Pablo Mayo Sanz
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What is the battery light?

The battery light is perhaps one of the easiest to recognize. Unlike many other car lights often represented with strange shapes, the battery light is the one represented by a simple battery.

From a graphical point of view, the battery light is represented as a rectangle with a + and - inside it. Obviously this rectangle and the plus and minus signs represent the positive and negative poles of the car battery. In terms of colour, the battery light is almost always red, but on some cars it is also yellow.


We must remember that the battery light represents not only the battery itself but also the car's alternator. Therefore, any problem with the alternator can result in a battery light coming on.

Why does the battery light come on?

The battery light coming on can indicate several types of problems related to the car's electrical system. The battery indicator light illuminating is almost always due to a problem with the car's battery or alternator. This is because the electrical circuitry in modern cars is very durable and is unlikely to be damaged as a result of a battery light coming on.

Therefore, with a red battery light on we can have the following problems:

  • Low carbattery - this is perhaps the most common cause of a battery light on. The symptoms of a low battery are many and easy to notice.
  • Alternator problems - this component is responsible for generating electricity while the car's engine is running. Any damage to the alternator is detected with a battery light on.
  • Corroded electrical wiresor f uses - simply cause one of the car's electrical wires to become corroded or cut so that the battery light comes on.

A check of the battery and alternator by a mechanic usually solves all the doubts about the battery light coming on. So don't panic, let's trust a professional to tell us how to proceed.


Why does the battery light stay on?

Very often you find yourself with the battery light on. Then you proceed to recharge the battery but the battery light stays on. So what do you do?

Chances are the battery light stays on because the problem is not with the battery but with another component in the electrical circuit. The options are few and as mentioned above it could be an alternator failure or a problem in the electrical circuit.

Both of these problems are difficult for the average driver to diagnose and therefore a professional is needed. So let's find a mechanic or electrician, tell him that the battery light stays on even though the battery is working and let him get out of the car to check.

The specialist will usually check that there are no broken or cut wires and can therefore indicate the best procedure to remove the battery light stays on.

How come the battery light stays on but the alternator is charged?

Another problem we get called several times a month is a battery light that stays on but the alternator is charged. If we are sure that the alternator is working and producing electricity, then the problem may be in the electrical circuit or in the battery.

If we have no problems using the various electronic equipment in the car, then we can exclude that the problem is in the electrical circuit. Very often we simply have an old battery that has run down. When the battery is too old it does not hold a charge and this can cause us to find the battery light on.


We recommend you take a look at our article where we explain the average battery life of a new car. This way you can see if it's time to replace yours and solve the problem with the battery light on.


What to do with the battery light on and hard steering?

Many people wonder how a simple car battery problem can compromise and make the steering of the car hard. Well, we have to remember that in a modern car the only component that is perhaps not dependent on electricity from the battery and alternator is the ashtray.

Steering the car can become very difficult due to a problem with the electric power steering. In case of battery failure, the power steering may not receive electricity, making it very difficult to steer the car.

With the steering hard and the battery light on, we should assess if the car is safe to drive before we get to a mechanic. Also remember that a moving car is much easier to steer than a stationary car.

What to do if the battery light comes on and then goes out?

This is the last question we are often asked: What to do if the battery light comes on and then goes out? The best answer is to do a battery and alternator check anyway.

That said, the battery light coming on can also be due to a simple voltage drop and there may not be a problem. If it only happens once, there may be no problem. If it happens often, then the car should be taken to the mechanic.

Frequently asked questions and answers

If this happens, you should visit a workshop to check the battery power, and then decide whether to repair or replace the battery with a new one.
23 Jan two thousand and nineteen

In order to diagnose if the problem is the dead battery or the alternator, it is partially simple.
Simply when someone passes you power to learn the vehicle, remove the cables and wait.
If the alternator fails to recharge the battery, the car will stop working.
29 Feb two thousand twelve

To indicate the state of charge, some batteries have a built-in sight glass or magic eye on the top of the battery.
The green color means that its charge is complete.
The white or transparent color means that it needs to be charged.
Black indicates that it needs to be replaced.

Rapid flashing indicates an imperfect connection between the battery and the charger or a problem with the battery.
Remove the battery from the charger and now use a dry cloth or cotton swab to clean the metal terminals of the battery.
Now try to charge the battery again.
23 may two thousand and twenty two

Compilation of frequently asked questions that our users have sent us and that our experts have answered.

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