What causes the cruise control to stop working?
What causes the cruise control to stop working? Most common cause of erratic cruise control? Vacuum leaks caused by deteriorated hoses. Cruise control on your vehicle is a terrific device. It substantially reduces the driver's workload on longer trips, and can save substantial amounts of fuel and expense over the life of the vehicle--until it stops working. How does a cruise control system work on a truck? Some older systems, used on cars or trucks that don't have throttle-position sensors, may have a rod that moves in and out of a magnetic coil to tell the controller the throttle position....