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Understanding your car's electrical components
Many people might think a battery is all it takes to power a car. In reality, there are many components that help run items like the stereo, air conditioning unit and other electrical displays, such as the speedometer and odometer.
A car's battery typically transfers energy to the alternator, which recharges and energizes the electricity that's distributed throughout the rest of the vehicle. Other components include the fuse, switch, relay, wiring, electrical connectors and computer PCM. The function of the fuse is to stop the voltage flow during times of overwhelming electrical patterns or short circuits.
Many new vehicles are dependent on the computer PCM to operate, and some of them simply won't run without it. This unit is responsible for transferring the power from fuses to the rest of the vehicle.
Sometimes headlights will begin to dim, which can be a sign of multiple issues. In this scenario, a volt meter can be used to determine the battery's voltage. If car owners experience electrical problems that have nothing to do with the battery, these other components should be thoroughly examined by a certified mechanic to determine the cause.