Modern cars are built with all sorts of sensors that help you identify problems quickly. Usually, there is a warning light on the car dashboard to alert you immediately a sensor picks up a fault. One of those warning lights is the car battery light. The icon looks like a car battery. If you are driving and the battery light comes on, that tells you the battery is not being charged.
Driving a vehicle in which the battery is not being charged means that in a matter of minutes, the battery will empty, appliances and lights will turn off, you will lose power steering control, and eventually your car grind to a halt.
What to do: pull over as soon as possible to have the problem solved. If you were not moving yet and the battery light comes on, you are better off switching off the engine and calling for a trained personnel to have a look.
Below is an explanation of what is wrong if your car battery light comes on while the engine is running.
Battery Light And The Alternator
The device that charges your car battery while the engine is running is called the alternator. A charging problem means that the alternator is disconnected or faulty, or the alternator belt is broken.
A quick check for those three possibilities will nail the problem. Either the alternator has to be repaired or replaced, or the alternator belt replaced. Once the problem is fixed though, depending on how drained your battery is, you may need another battery to start your car or you may need to have a battery charger top up the battery.
Verify That Your Alternator Works Now
After fixing the problem, when you start your car again, the battery light should turn off now. Another way to be sure things are working fine again is to start the car, then disconnect the battery. If the engine keeps running, your alternator is working fine. If the engine dies when the battery is disconnected, the problem is not yet solved and you should have a look again at the possible issues listed above.
Note: Unless you have the skills, you will need a trained person to sort out any alternator troubles your car may have.