Advice for newbie

[Thinman]

OK, thanks to your answer, I think I figured it out after thinking and remembering. I didn`t think about it at the time I was so busy trying to think of everything I should be checking. I only sat in the cab long enough to check oil pressure, air pressure and the cab in general. I think there was a piece of tape on the tach face. So I dug around on the net and found the location of the check engine light.....voila....I think the tape was covering the place where check engine light is.