mine works like a charm..Coming on when we slow down and turning off once we speed up. Or I can turn it on and off manually. Yours must not be working correctly. Ours makes a HUGE difference in the heat we feel, on of the best add one of done and would recommend it to anyone

I turned the fan off while we were sitting in Sturgis traffic this weekend to show the wife the difference if made. She loves this thing...and it wasn’t even that hot out in our opinion either