Cruise Control: Description and Operation

The speed control system is operated by means of five switches on the steering wheel. The functions are:

Switch Function
ON Activate system
OFF Deactivate system
SET/ACC Accelerate and tap-up
COAST Coast and tap down
RES Resume

The speed control unit provides signals to the stepper motor housed in the actuator. The stepper motor moves the throttle body cam by means of an internal geartrain and a cable linkage. The vehicle speed sensor generates the reference signal that the control unit compares to the speed setting selected by the driver. If a discrepancy exists, the stepper motor will adjust the throttle body cam setting, correcting the vehicles speed.

Any of the switches operated by the brake or clutch pedal (vehicles fitted with manual transaxle) will interrupt the speed control operation by releasing the speed control actuator cable and returning the throttle body cam to the position set by the throttle pedal.

STEPPER MOTOR







When the speed control system is activated, the windings in the stepper motor are energized by the speed control actuator which makes sure accurate positioning of the throttle body cam. The vehicle road speed then settles to the speed selected by the driver.