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Did my failing alternator murder my brand new car battery?

I have a 2008 kia spectra that is just an A to B car. I know it needed a new transmission control module when I bought it but those repairs would cost more than the vehicle is worth. So I have been driving it to and from work for months now and I have experienced the occasional sputtering but it has always started and run great. I even took it to Auto Zone and the diagnostic test didn’t mention anything other than the transmission problems I had already known about. But a month later the car’s battery dies and will NOT hold any charge from chargers themselves or from the alternator. So I assumed it was a dead battery and buy one brand new. I bought the battery and installed it. My car started right up and ran well but the battery indicator light and parking brake indicator light would not go off. That evening it experienced the exact same problem with the brand new battery. Great so I figure it’s the alternator. But if it’s the alternator, shouldn’t the battery be capable of charging up when put on a stand alone charger? Both batteries would not hold a charge at auto zone. Even the one I literally bought Yesterday. So my question is…is something like my bad alternator causing my batteries to short out permanently? And is that even possible with a brand new battery? And what else could it be if it’s not necessarily the alternator? Is the faulty transmission solenoid somehow murdering my batteries for good? Are all my car problems stemming from a defective transmission control module? Because it has operated fine for a year and a half with the transmission slipping like that. It was only last week that something began to strangle my battery forever. Help!!

Let’s get down to the basics. Do you own a multimeter? If not, buy or borrow one. A charged battery should read about 12.6 volts, key off. Start the car and now the voltage should read at least 13 volts to about 14.5. If it does, the alternator is OK. If it doesn’t the alternator might be bad.

If you unhook the battery negative cable and measure amps across the battery post and loose clamp, it should be very low. Key off, doors shut, wait 2 munutes and the reading should be well less than 0.10 amps.

If this is beyond your abilities, it needs to go to a pro.

you took new battery back to AZ and they said it will not hold a charge after they tried to charge it? so they said you wrecked it? and did not replace the new battery?

Follow the perfect instruction you got from @Mustangman . If your new alternator is pumping out 25vdc or as high as 78vdc… you are frying your new battery. I have seen those numbers before and the results aren’t usually pretty, we collectively need to know the alternators output. In a bad way.