Check Engine Light!

Oh boy! A friend of mine has a '92 Honda Prelude. It has an aftermarket performance chip in it with DC Sports intake, DC Sports exhaust and no other mods. The "check engine light" just came on today and he is wondering what it means. Actually, so am I but that is besides the point (lol). It has about 120k on the odometer but it runs well and has been maintained. We are both wondering what has to be done to the car... is it a valve, or sensor that needs to be replaced? HELP, PLEASE!

Thanks all!!!!

Cyber