Make sure that you check for the corrossion as said before. You may also have some corrossion on the inline fuse holder that could be causing the resistance that makes your unit go off. If you have rust or corrossion on the inline fuse holder, you should get it replaced as cleaning out the inside of the holder would be extremely diffucult, and there is no way that you could know if you got it all or not. You may also have a bad braid of wire on the inside of the insulation. If your battery is older, you could have the cells on the inside coated with sulfur causing your current and voltage to not be what they should be. As said before, check what your voltage on your battery drops to when you start with with a Volt meter. If its anywhere close to 10 (10.6, 10.5 or lower) than you know that you either have too many things hooked to your battery at once, or you have a battery that needs to be replaced. I hope this helps you out bud.