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Q: Battery draining over night when cold outside

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How do I find out what's draining my battery overnight only in the cold weather! Nothing is being kept on?

My car has 114200 miles.
My car has an automatic transmission.

Hi there. The most common cause of a battery draining when it is cold outside is simply a failing battery. When a battery is old and becomes weak it will drain in cold weather. I usually start by load testing the battery. If it fails then it needs to be replaced. If not then most of the time this is caused by an ignition switch that is shorting when it is cold or a failing body control module. If there are not any other electrical concerns then it is usually the module that is failing. If you need to have this battery issue looked at, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the battery is draining] https://www.yourmechanic.com/services/service-battery-cables

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