battery or alternator problem??

[spamking98]

Hi, I was wondering if anyone knows what the problem would be if your lights in your cluster dim when you turn on the ac full blast while your car is running or when your driving and your car starts to stall while in a stopped position... and eventually dies... would this be the battery or the alternator.. I did the voltmeter test on the battery while the car was running and I got 14.3 volts...I also pulled out the negative battery cable while the car was running and the car was still running... so does this mean that the alternator is still good..?? I tested the battery with the voltmeter when the car was shut off and it read 12 volts...I tooK a long screwdriver and placed it on the alternator to hear if anything was grinding and there was some sounds that were pretty loud but Im not sure what a bad sounding alternator is supposed to sound like...or a good one...if you can help please let me know thanks

[butundo]

That sounds like a dead cell in the battery. The only way to test the battery is to put a load on it. Any local auto store should be able to test for free. I replaced my battery not to long ago. I believe it is a Type 49. The stealer wanted $149. I bought my at the local Sams club for around $65. I did start to have some electrical problems after a week or 2 of replacing the battery. After much troubleshooting and searching on the internet and this site, I finally resloved the issue. I had to unplug the battery for a few hours to let the computer reset. Once I did this, my random electrical problems went away.