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Q: Battery draining after new alternator installed

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The alternator is new, but the left battery has 60% life. I hope it is normal because the volts show 14 volts.

My car has 198000 miles.
My car has an automatic transmission.

Hi, thanks for writing in. It’s very common for mechanics to forget to replace alternator sensors or charging wires to the battery when they replace the alternator. However, one other item that directs the flow of electricity to the battery is the battery temperature sensor. Usually it’s installed underneath the battery and triggers flow to the battery as the battery temperature decreases. They are supposed to last a long time, but dirt, debris and other "stuff" can clog or wear this sensor out prematurely. If you would like help with this replacement, consider having an expert automotive technician from YourMechanic come to your home or office to perform the replacement for you.

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