‘Why does my battery keep dying?’

The Car Doc weighs in.

2013 Subaru Legacy.
2013 Subaru Legacy. –Subaru

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Q. My Subaru battery died after I used my cellphone for 20 minutes while sitting in the car with the engine turned off. This also happened when I used my laptop while sitting in the car. What do you think?

A. Over the last few years, Subaru has had its share of battery issues, but I’m not sure this one is just a battery issue. Years ago, cigarette lighter sockets with 12-volt power points were always powered when the key was off. This isn’t the case with most vehicles today. The key or push button needs to be in the accessory position. These additional systems plus the cell phone or computer may have been enough to drain a four-year-old battery. If this were my Subaru, I’d replace the battery with one that has the highest reserve capacity possible. I’d also limit accessory use.  

John Paul is AAA Northeast’s Car Doctor. He has over 40 years experience in the automotive business and is an ASE certified master technician. Email your car question to jpaul@aaanortheast.com. 

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November 9, 2017 | 3:22 PM