Water temp got up to 250 and chimes started. Pulled over, turned on heater. Thought maybe low coolant, but level is fine. Then I noticed the rad fan wasn't running. I thought maybe blown fuse. The diagram under the fuse box lid says k1 rad fan lo, k2 rad fan hi, f1 rad fan power, f3 rad fan hi/lo. All those spots are empty in my fuse box. What gives?