2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 423Get this manual
ELECTRICAL Speed Control Diagram
The speed control system utilizes the ECU, Speed Sensor, Solenoid Valve, and engine vacuum from the throttle body to operateThe ECU powers the system through the ECUIGNFUEL RelayWhen the speed sensor signal rises over 40 Kph (25 Mph), the ECU triggers the solenoid valve to open, allowing atmospheric pressure on top of the air control body diaphragm which limits the amount of air entering the engineOnce the vehicle speed drops below 37-40 Kph (2325 Mph), the solenoid valve is closed by the ECU and the operation repeatsShould the vehicle speed reach 67 Kph (42 Mph), the check engine' light will illuminate on the LCD gauge to indicate there is problem with the system