I know this question has been beaten to death but I need a second opinion so I can sleep tonight. My 2002 TJ will not crank. The gauge blink and the needles jump all around. The battery is reading 12.4 volts but when trying to crank it drops to 6.8 volts. It returns to over 12 after you stop trying to start. Everything I read says bad battery. It has been lazy starting since I bought it a month ago and the battery is at least a couple years old.