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Q: Parasitic load on battery.

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The battery drains while my car is running.

A: Cars basically use the battery at start up....

Cars basically use the battery at start up. Once the vehicle is running the alternator takes over and provides the car with the electricity it needs to run. If the alternator stops producing the electricity the car needs, the car simply starts taking it from the battery. The car will continue to run until it drains the battery then it will turn off. A technician will be able to test your charging system and determine if the alternator is the culprit.

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