optima batteries are aggravating to deal with. we had our cranking battery go completely dead. I called advance nad they said to bring it to them adn they would have to force charge it on their machine becuase they are gel batteries and if ran completely dead they wont take a charge back but by two ways. They charge it or take a regular deepcycle battery and hook jumper cables to it and then hook the other end of the cables to the optima and then hook the charger up to your regular battery and then it will take a charge. I am not impressed with the optima batteries at all to be honest with you. Ours hold up to all day fishing and such but my cranking battery everynow and then will draw down and it seems like over night and i know nothing is hooked up cause i throw the breaker to all the power. But i believe my culprit is my powerpole that is hard wired to the battery. I hope this helps.....