Q: Battery dies if the car sat for over 20 hours

asked by on July 25, 2016

Since I purchased the car, I had to get the battery replaced over ten times. It just keeps dying. I had the battery load-tested and it checks out fine as well as the alternator. However, each battery dies if a day goes by that I don't drive the car. I was told that I had to drive it every day so as to prevent the battery from getting drained. There are no dash warnings nor error codes. Only the MAP light that occasionally comes on and won't turn off the car even when the engine is off. What could be causing the battery to die out so quickly?

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Batteries that drain overnight are common. Usually when this occurs, there is a parasitic drain on one of the car’s systems. When this occurs it drains the battery down over time. Batteries that are drained down repeatedly can cause them to fail. The most common causes of the battery drain are aftermarket accessories, radio, power windows and seat motors. If you can find the cause of the parasitic drain, a certified mobile technician from YourMechanic can come to your car’s location to diagnose your battery and determine what should be done.

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