Your best place to start would be using the forum's search function.
In a computer-controlled car, 'dummy light' is somewhat simplistic. In simple terms, the car is trying to tell you something is wrong. The computer keeps an internal memory of any errors it has encountered for later diagnosis.
There is an easy process to 'pull the codes', which will give you specific error codes which should help lead to diagnosing & correcting the reason(s) for the warning lights.
Visit
http://www.shotimes.com FAQ section for information on how to read the codes (all it takes is a paper clip, pen and paper), their meanings, etc. The forum's resident SHO expert, sdpatt, also has a good site which has more information on the EEC-IV system and codes, and he'll probably mention it, although I'm sure if you search you'll be able to find it quickly.
Also, when you use the Forum's search function, you will find countless messages regarding interpreting and diagnosing common problems. Just search under 'check engine'.
Another option would be to take the car to AutoZone, where they will check the codes for you at no charge.