A little late but here's my take. Clean your battery terminals. Make sure the starter lead is good and tight. Charge the battery overnight. Try it out. A couple things to comment on also. Using your charger on the start engine option will not give enough cranking amps go wrench the starter out of your hands, like it should on a fully charged battery. This may be a stretch but bear with me. When you try to start the jeep, and all you hear is a click, the starter is engaging, but may not have enough amperage to turn the engine. You will still have 12 volts with no load, but not the amperage required. Your troubles may very well be dirty terminals, poor ground, poor connection on the starter or most likely a dead battery.