Rubicon 500 electric issue

I just recently sunk my rubicon up to about gas tank height it died when I got it out I drained all of the water out of the exhaust air box was dry so It started right up so I rode home the next day I rode it again fine when I parked it for about 3 days I go to turn the key nothing happens so I assume dead battery but nope battery was fine so I pull started it and it started fine the dash turned on when I would rev it it would die at low rpm and flash in different gears when I would try starting it back up the the electric start would do nothing. Now it won’t doing anything at all even with a charged battery. What should be the first thing I check?