I've had my 2013 JKU for about two weeks now. It had 9,800 miles when I bought it and seemed to be problem-free. I'm driving along this evening and all of a sudden, "DING," and the check engine light's on. Nothing feels abnormal, the gas cap is on tight, and I get nothing when I check for codes. The only thing out of the ordinary that I've done lately is climb a muddy hill in 4-hi. Thoughts? Thanks in advance.