Cruise Control System Circuit Description

The cruise control system maintains a determined vehicle speed under normal driving conditions. Any steep grades upward or downward may cause slight variations in the desired speed. The cruise control system is able to perform the following functions with the vehicle speed:
^ Maintain
^ Coast
^ Accelerate
^ Resume

The cruise control servo is the main component of the cruise control system. The cruise control servo allows the system to control and maintain the desired cruising speed. The cruise control servo monitors the vehicle speed through the Vehicle Speed Sensor (VSS). The VSS maintains or varies the vehicle speed. The VSS responds to the input from the cruise control main switch.

A servo motor is inside the actuator. The servo motor turns the worm gear. The turning worm gear causes the accelerator cable to move in order to adjust the throttle angle. The servo motor and the worm gear are connected mechanically only when the magnetic clutch energizes.

The cruise control disengages when the cruise control servo receives a cancel signal from the following components:
^ The stoplamp switch
^ The cruise control main switch
^ The cruise control release switch
^ The transmission range switch (automatic transmission only)
^ The Clutch Pedal Position (CPP) switch (manual transmission only)

Upon receiving a cancel signal, the cruise control servo de-energizes the magnetic clutch. This disconnects the servo motor from the worm gear. When the worm gear disconnects, the throttle returns to the idle position. Note also the resume feature is inoperative when speeds fall below 25mph.