Cruise Control Servo: Description and Operation

PURPOSE
The speed control servo is used obtain and maintain a selected road speed.

CONSTRUCTION
The speed control servo houses the throttle actuator, speed control vacuum solenoid, and speed control vent solenoid.

OPERATION
The Powertrain Control Module (PCM) operates the speed control vacuum and vent solenoids, by switching the ground path on and off. Power to the solenoids is supplied by the speed control relay.

When the PCM grounds vacuum solenoid, the speed control system opens the throttle to obtain a selected road speed.

When the PCM grounds vent solenoid, the speed control system closes the throttle to reduce road speed.

The PCM balances the two solenoids to maintain a selected road speed.