I just got a new battery 10 days ago and my alternator is new and my car won't start.
My car has 12600 miles.
My car has an automatic transmission.
Without additional diagnosis on the vehicle to check to see if the charging system is working correctly to recharge the battery or if the battery is having an electrical draw on it making it go dead will be hard to isolate the cause in this venue. I have seen aftermarket alternators not work correctly since the system is computer controlled and they tend to not charge correctly and cause the battery to go dead. Make sure charging system will keep up with all accessories on and voltage stays above 12.8 to 13.2 volts with lights and blower on. If not then alternator or computer may be at fault and will need further testing to isolate cause.
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