Dodge 4x4 warning light

I just bought a Dodge 1500 5.9L 4x4 (no owners manual) I have got a warning light that looks like an engine (I assume check engine) every thing seems to be running good, oil pressure/level good. Any suggestions? anybody know what the owners manual says?

onmy 2000 1500, mine just came on too....manual says the usual crap, take it in and get it checked out, im going to check my air cleaner next, then maybe some other stuff, right now im trying to figure out if there is a way to "reset" it, or turn it off..i have heard of this being done in other trucks.....