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