interior fan will not shut off
 

I'm new to this website and I did a search prior to posting a new thread and found nothing similar to my problem. I have a 1996 saab 9000 with 200,000 miles. My girlfriend was driving yesterday and the check engine light came on and the interior fan kicked on and will not go off, all within five miles. I took it for a drive to try to figure out the issue and noticed that the temp gauge was at 6:30 and after I drove for about 15 miles the gauge did not go above 7:00. Will the thermostat trigger the check engine light and make the interior fan kick on? or are all these different issues? Please help.