2008 Sebring heater motor Problem with ATC
 

I have a 2008 Sebring Limited(3.5)with Automatic Temperature Control(ATC). 2 days ago the blower motor started working intermittently. It makes no unusual noises when it operates. I took it off of AUTO and set the fan to High so I could hear it come on. I also set the heat to 80 so I know it is not turning off because it has reached the correct temperature. I took a 20 mile trip yesterday and the fan came on twice for 30 seconds or so and then shut off. Later when I was at a light I could hear the fan running faintly. The fan was trying to go faster but it would go back down to near zero and then increase a little back and forth. I think the fan is fine but it is like a thermostat type sensor is operating intermittently. If anyone has any suggestions I would like to hear them. It is getting cold in Pittsburgh.