General Description
DESCRIPTIONThis 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 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.
ELECTRONIC CONTROLLER
The ECM or PCM receives input signals from the cruise control engagement switches, brake release switch, drive switch and speed sensor.
On models equipped with DFI or PFI, the ECM or PCM also receives engine control signals. The ECM then processes these signals and transmits a command signal to the solenoid valve, regulating vacuum to the servo unit diaphragm. This is a test of the insert key.