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 De-activate system
SET/ACC Accelerate and tap-up
COAST Coast and tap down
RES Resume



The 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 vehicle's speed.

Any of the switches operated by the brake or clutch pedal will interrupt the speed control operation by releasing the speed control actuator cable and returning the throttle body cam to idle.





Speed Control Actuator
The speed control actuator is mounted on the right-hand inner fender behind the suspension unit top mount. The speed control actuator incorporates the following components:
- The electronic speed control unit
- The stepper motor and geartrain, electromagnetic coupling and reduction gearing





Speed Control Unit
The speed control unit evaluates incoming signals from the system sensors and switches. It actuates a stepper motor and cable linkage to adjust the throttle body cam, maintaining a constant vehicle road speed.

If the vehicles brake or the clutch pedal are depressed, the speed control unit interrupts the speed control operation.





Stepper Motor
When the speed control system is activated, the windings in the stepper motor are energized by the speed control unit ensuring accurate positioning of the throttle body cam. The vehicle road speed then settles to the speed selected by the driver.