I know this is a silly question but here goes. Today I went to a car show. I turned off the car and fan ran until rad was cool then shut off. Three hours later it started to pour rain and I hear the fan running again. Checked temp and was cold? Why would the fan just kick on because it was raining. It wouldn't shut off had to pull wire off. Then when I left it was OK? That was really crazy! Thanks for the help