Cruise Control: Description and Operation

This Cruise Control System utilizes vacuum to activate the throttle servo. Throttle position is changed when the servo unit diaphragm receives varying levels of vacuum, controlled by a solenoid valve. The solenoid valve modulates the vacuum signal to the servo in response to commands from the electronic controller. The electronic controller monitors signals from the engagement and instrument panel switches, electric brake release switch, and the speed sensor. The speed sensor, signals vehicle speed to the controller. These signals are used by the controller to activate the solenoid valve, regulating the level of vacuum to the servo diaphragm. This system uses two brake release switches. An electric brake release, mounted on the brake pedal support, turns the system Off and vents the servo diaphragm to the atmosphere through the solenoid valve. A second brake release switch, a vacuum release valve also located on the brake pedal support, vents the servo unit to the atmosphere.