2002 Voyager- Check Engine Lite On...

I've got a 2002 Chrysler Voyager, just hit 75,000 (and end of extended warranty)  now my Check Engine light has gone on, (steady on not blinking)  Other than that vehicle seems to be working just fine.  The light worries my wife...  Some possible causes for this??

yeah  over 1000 possable causes  get an an auto parts store to run the code or may a tech to look at the code and go from there. The light is on because of federal mandates causing some sorta emissions prob in some way.