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Cruise Control Servo: Description and Operation




FUNCTION

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


OPERATION

The PCM operates the speed control vacuum and vent servos, by switching the ground path on and off. Power to the servos is supplied by the speed control relay.

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

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

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