acc fan speed controller

Hello, So i have a problem with my -97 Saab 900. The fan that blows heat/cold into the car isnt working properly, or rather, the fan works itself, but something else isnt. When i start the car and the engine is cold, the fan blows air from the air channels normally. But as the engine gets...

It's getting close to winter up here in Minnesota and my blower motor is working intermittently. It will work for a week and stop for a day or two, and then start back up again. I need to get this fixed as soon as possible. The ACC unit still shows that it's blowing air when it's not. Any ideas...