What is the best diagnostic procedure
My car has 100000 miles.
My car has an automatic transmission.
You need to have the alternator checked and then the battery. Sometimes the alternator charges fine but the cable between the alternator and battery is bad. If so, it will not charge the battery. The cable from the alternator and battery has a built in fuse that may blow out form improper jump starting or a shorted battery. You should have the vehicle checked by a certified mechanic, like one from YourMechanic, to diagnose your dead battery and help you fix it from there.
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