The Alternator helps keep the car’s battery charged to provide power to the electrical components of your car—headlights, instrument panel lighting, windows, radio, etc. The alternator is powered by the serpentine belt. Like any mechanical part, the internal parts in the alternator can wear out over time. This will cause your car to suddenly “die.”. This could be the result of a bad alternator, or it could be a bad battery or broken serpentine belt.