I have a 13 800s. When running with no accesories on my battery is reading about 14 volts. Turn on the 30in light bar and drops 12 and under and will stall unless I give some throttle. It even sounds bad with just the front lights on. I took the battery out and put it in a 2010 model I have with the same accesories and will hold 13 volts running with all accesories on. Cannot tell if my battery is bad or something else. Any help?