I drove a lot yesterday but the last place I drove I stayed at for around 3 1/2 hours and the temperature out side was in the 30s. My fans were off while I was at this place. I got home at around 3 AM this morning the fans were on and I thought nothing of it because they have done so in the past. I wake up at 11 this morning and the fan is still running. The driver side fan (which would be the right if your standing in front of the car) was still going. So I unplugged the battery checked my radiator and water hoses. Nothing was out of the norm. I pulged the battery back up and again the fan began to go. Its only one of the fans not both. I unplugged the battery again and unplugged the fan that was running. Any ideas on what is causing the fan to go continuously for many hours? I mean the engine isn't hot nothing is hot. Is there something I might be able to check out?

I'm stumped.. Help!