Hi,
I live in Minnesota. My car was dead couple of months back (around Halloween when temp drops significantly). I replaced new battery as it was 5 years old. It worked couple of weeks, but after few days or even overnight, the car power is dead, unable to start. If i use jump starter external battery, the car starts and i am able to go around entire day. However, the next day the same story repeats. The car is dead and doesn't start without Jump starter. Is this new Battery issue OR some other problem? Any suggestion will be greatly appreciated.

Thanks.

 

Check for parasitic draw. You likely have a switch that is keeping the BCM awake.