Hi I have a 97 sentra with a 1.6 motor, 5 speed. I notice that the fans dont turn on, only when I turn on a/c does the fans trun on. I let the car run for 1/2 hr and the temp. gauge goes just above 1/2 way, but no fans. Has anyone had this problem. The car has not overheated, I just notice this problem this week.