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Cruise Control Servo: Description and Operation

PURPOSE
Actuated by the PCM to obtain and maintain a selected road speed.

Houses the throttle actuator, speed control vacuum solenoid, and speed control vent solenoid.

OPERATION
Power to the solenoids is supplied by the speed control relay.

The Powertrain Control Module (PCM) actuates the vacuum and vent solenoids, by switching the ground path on and off.

- 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.