Well i have a chevy s10 ext and im not really sure how many volts the alt is but I am having a lot of trouble with my lights dimming. My amp is a Kicker ZX1000.1. We have a 12v battery up front and a second battery in the back.. My buddy has told me about 15v batteries, would this stop the problem? when I am driving I dont have any problems but once i stop at a red light with the heater on it will sometimes kill the motor and it dims the lights really bad.. My dad keeps getting pissed off because he already has over 1500 in my system and we keep running into more problems, any ideas?