Volvo: Check Engine light, haynes manual, free question

Question
Happy Holidays and thanks for your time.  The "Service" light came on the instrument cluster of my 1990 240. I reset it after I did the oil/filter change.  The mileage is currently 118,000.  But the "Check engine" light came on too.  All the fluids are fine. I also changed the tranny fluid and filter as well as draining the rear axle oil and replaced it.  What do I check for and how do I reset the light?  I couldn't find it in the Haynes manual.

Answer
If all the fluids are fine, I would guess that you probably triggered your oil pressure sensor while you were changing the oil, and now the light only needs to be reset.  Unfortunetly my only resource for doing that in a newer 240 car would be the Hayne's manual that you already mentioned didn't have the answer.  So I'm going to recommend you take the question to www.brickboard.com and post a free question in the 240 forum section where you can get an answer from someone who has reset it on their own car, because mine is so old it doesn't even have one!  Sorry I could help, but brickboard will have what you need.  Good luck!