How the Electrical System Works

Almost everything on a modern car relies on electricity. This electricity comes from both the alternator, which generates energy, and the battery, which stores energy generated by the alternator. The amount of electricity your car is using at any time is called the load. How much load is on the system will determine whether the car draws power from the alternator, the battery, or both.

The following are some of the primary components of the electrical system.


Battery Your car has one or more batteries to store electricity. The starting system requires a lot of power, which it draws from the battery. Once the ...

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