[57chevyragtop]

whoa! Are you sure about that air pressure? way too high should be 30-35 psi that might be why you get the message...double check that pressure when tires are cold (before driving, which warms them pretty quickly and causes pressure increase) As for the OnStar button I think that lights up green when system is on, it's a subscriber service around 18 bucks a month, I don't use it so you may get a better answer from others. Onstar subscription info 1-888-864-2801, 8AM-6PM EST. If you mean user/owner manual I don't know of any online but might check Ebay or other auction line.