How Does the Alternator Affect the Car?
While many people believe the car battery does all the work as far as operating the electrical system in your vehicle, it is, in fact, the job of the alternator to keep all those things operating without fail. The battery will provide power to the starter motor, and once the engine is running, the alternator takes over. The alternator will power the stereo, lights, door lock, power windows, and navigation system.
The alternator in your vehicle works like a generator and gets its power from the crank wheel that spins quickly when the car is running. Pay very close attention to a failing alternator because things get bad very fast. If the alternator is failing, the first signs will be gauges failing on your instrument panel and the headlights appearing to be very dim. If you notice the alternator is failing, the team at our Jaguar service center in Austin, TX can perform an electrical system inspection.
Source: Jaguar Austin Blog