HORN, Horn Wiring Diagram for Ford F-Super Duty 1990, List of elements for Horn Wiring Diagram for Ford F-Super Duty 1990:, 30a, Fuse 16, Fuse panel, G207 (on steering column), High pitch (left front of radiator support), Horn relay (right side of i/p), Horn relay jumper (right side of i/p), Horn switch, Hot at all times, Low pitch (left front of radiator support), Nca, Slip ring, Speed control switch, W/ speed control, W/o speed control, , , POWER WINDOWS, HORN, RADIO, POWER DOOR LOCKS, STARTING/CHARGING, WIPER/WASHER, ,