Sportsman etx won’t start

I went to start my atv yesterday and it wouldn’t… So I charged it and the battery works with my strobe lights I have installed but other than that it won’t give the atv and power on the display. I left it in my truck over night and it was 90 degrees out and then when I went to take it out after work there was a liquid that was on my rubber floor mats. Don’t know what it was but it kind of smelled like a faint vinegar. But keep in mind the strobes still work some how. Any help will be great. Thanks in advance