The car alternator is essentially a power generator which keeps the car battery charged and allows it to continuously power the key electrical components of the car. Without this, the battery would be drained quickly as it does not have the power to supply electricity to all of the components for extended periods. The alternator is attached to the engine by brackets and bolts. It is powered by the crankshaft mechanism and driven by a belt.

In the past, car engines used several separate belts, such as V-belts, for various engine units. The alternator was driven by a separate drive belt, which wrapped around the crankshaft and alternator pulleys. Nowadays, the large majority of vehicles use one belt, known as a serpentine belt, to drive multiple units, including the alternator, power steering pump, water pump, air conditioning system unit. These ribbed belts are designed to maintain as much contact with the pulleys as possible to increase the power transmitted. If the belt gets damaged, these units will stop working and, as a result, the car’s power system could shut down.