Another problem?. My cruise control is working eratically, it will come on and engage, but then speeds the vehicle up and then kicks off when it reaches about 65mph. It is in a foretravel unihome with a catapillar deisel 3208...any thoughts?
If it is a King Control, it is possible that the ground is not making good contact or has become corroded. The control box is usually in the enginge compartment so it is not difficult to find.. Check the ground on it.
Another thought: It used to be that the cruise controls sensed speed from a coil looking at a magnet attached to the driveshaft.
In later years, in most applications, they used a direct connection to the vehicle speed sensor line.
It sounds as though that connection is not hooked up. The cruise control will power up, but is searching for a clue as to the speed of the vehicle. Finding no (or what appears as invalid) data, it failsafes by disengaging.