So I was going to go trail running with a friend of mine today and when we were leaving my "Service Engine Soon" light came on...ok so I stopped and looked for leakage of any kind and everyhitng seemed to be in order except for one thing. My Positive battery's nut came loose and fell of the bolt...so the connection isn't perfect. So I replaced the nut and tightened and still with the light... Everyhitng runs fine and sounds normal...I ended up doing the trail run anyway and no problems whatsoever. Anyone have any ideas at all?