Cruise Control: Description and Operation

The cruise control system uses mechanical, electrical, and vacuum-operated devices to maintain vehicle speed at a setting selected by the driver.

System Description
The cruise control unit receives command signals from the cruise control switch. It receives information about operating conditions from the brake switch, the vehicle speed sensor, the clutch switch (M/T), and the automatic transmission mode switch and powertrain control module (A/T).

The cruise control unit sends signals to the devices that regulate the throttle position to maintain the selected vehicle speed. The control unit compares the actual speed of the vehicle to the selected speed, and, based on the result of that comparison, opens or closes the throttle.

The brake switch releases the system's control of the throttle at the instant the driver presses the brake pedal. The switch sends a signal to the cruise control unit and the cruise control unit responds by allowing the throttle to close. The clutch switch and the automatic transmission mode switch can also send a disengage signal to the cruise control unit that allows the throttle to close.

System Operation
The cruise control system will set and automatically maintain any speed above 25 mph (40 km/h). To set it, make sure the cruise control main switch is in the ON position and, after reaching the desired speed, press the set switch. The cruise control unit will receive a "set" signal and activate the cruise control actuator.

Pushing the cruise control main switch to OFF cancels the cruise control by removing power to the cruise control unit which erases the set speed from memory. The cruise control system also disengages when cruising speed is lower than the preset speed by at least 12.5 mph (20 km/h). If the system is disengaged temporarily by the brake switch, clutch switch, or the automatic transmission mode switch, and the vehicle speed is still above 16 mph (25 km/h), you can turn the knob to the resume/accel position to reset the system. The set speed is still in memory so the vehicle automatically returns to that speed.

To gradually accelerate beyond the set speed without pressing the accelerator pedal, turn the knob to the resume/accel position and hold it there until the desired speed is reached. This will send an acceleration signal to the cruise control unit. When you release the switch, the system will be reprogrammed for the new speed. Quickly turning and releasing the resume/accel switch allows you to "tap up" up the preset cruising speed. Each turn-and-release increases the preset speed by 1 mph (1.6 km/h). The preset speed can be increased by up to 10 mph (16 km/h) this way.

To slow the vehicle down, press the set/coast switch button. This will send a deceleration signal to the cruise control unit, causing the vehicle to coast. When the desired speed is reached, release the set/coast switch. This will reprogram the system for the new speed. Quickly depressing and releasing the set/coast switch button allows you to "tap down" the preset cruising speed. Each tap decreases the preset speed by 1 mph (1.6 km/h). The preset speed can be decreased to a minimum of 25 mph (40 km/h) this way.