Cruise Control Servo: Description and Operation
DESCRIPTIONThe servo unit consists of a solenoid valve body, and a vacuum chamber.
OPERATION
The PCM controls the solenoid valve body The solenoid valve body controls the application and release of vacuum to the diaphragm of the vacuum servo. The servo unit cannot be repaired and is serviced only as a complete assembly.
SPEED CONTROL SERVOS-PCM OUTPUT
The PCM controls operation of the vacuum and vent solenoids inside the speed control servo. When the operator presses the on switch, the PCM provides power through the brake switch to the servo. When the speed control system is engaged following a set or resume, the PCM supplies a ground to the vacuum and or vent solenoids inside the servo as needed to maintain the selected vehicle speed.