Ok. I can run my car everyday and everything works, my car starts right up and then its fine an running an doesnt just die on me but if I sit in my car for about 10 minutes with it off an play the cd player - when I try to start the car all it does is click from the starter and then I have to have a jump from someone and then its okay again. It's like I can't run it for more than 10 minutes with it off. and my amp an subs use to power on but now I get a Low voltage light on my amp, so I know its not getting enough power either. I took a reading on the battery today with the car off and it had 12.6V which I'm guessing means the batterys good, right? is it possible that the battery could be bad but still run my car all the time? seems weird. How can I test my alternator and battery and what else can I do myself before I goto autozone an have them test it ( which they will prolly tell me I need a new battery so that I buy it from them) Please help me out everyone.