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Q: The car constantly drains batteries

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My car drains the battery. It happens every couple of weeks. I would go to start it up but it would be totally unresponsive. The battery was replaced but I need a permanent solution for this. What can cause batteries to become drained so quickly?

The symptom you have described is called parasitic draw. This occurs when the battery has a drain on it when the vehicle is shut off. Many different systems can cause this from the seat switch, electrical control unit (ECU), door lock computer, security functions and any aftermarket electrical parts that are installed. When this drain occurs, the vehicle’s battery is drained slowly while the car is off. If left for days or weeks it can drain the battery completely.

A qualified technician such as the ones at YourMechanic can perform a diagnostic inspection of the parasitic draw.

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