I have a 98 Volvo S70. A dashboard light that looks like a square with a fan in it just came on. What does it mean ? I have no manual to look it up

This light is the check engine light, its a picture of an engine, this is to let you know that theres a problem with the performance of the engine, what happens is that the computer is always monitoring all sensors and components and when its sees something out of spec it turns on the eng light and stores a code. the code well tell what part of a system has failed, for example it may say po301 cyl # 1 misfire. this would mean that the computer has seen cylinder 1 misfring , then with some checking and testing the problem can be found why the cylinder was misfiring, the first step you would need to do is have the compuetr scanned to see what code or codes are stored. there are many autopart stores that will scan the computer for free and give you a print out, if you could get me the codes i would be able to help you further, good day.