Description & Operation

Cruise control system uses a vacuum actuator to control throttle position, thus maintaining desired vehicle speed. Based on various inputs, cruise control unit controls operation of actuator solenoids. See ELECTRICAL COMPONENT LOCATIONS table.

When main switch is in ON position, system is ready to be engaged. Cruise control switch sets or adjusts desired speed. Cruise control switch contains SET, COAST, RESUME and ACCEL switches. System will not operate at speeds less than 25 MPH.

To engage system, accelerate to desired speed and momentarily activate SET switch. To disengage system, apply brakes, press clutch pedal (M/T) or turn main switch to OFF position.

To accelerate from a set cruising speed, activate ACCEL switch until vehicle speed is as desired, then turn off ACCEL switch. To decrease speed, activate COAST switch until vehicle speed is as desired, then turn off COAST switch. To resume previous set speed, activate RESUME switch (previous set speed cannot be resumed if system was disengaged using main switch).

If a fault occurs, cruise control unit stores a self-diagnostic code in memory. See RETRIEVING FAULT CODES under SYSTEM TESTING. Self-diagnostic system also includes an inspection mode that can be initiated to check individual components and their circuits. See INITIATING INSPECTION MODE under SYSTEM TESTING.

NOTE: System uses 2 switches to determine if brakes are being applied: cruise brake switch (dedicated to cruise control system) and stoplight switch (part of stoplight system).

NOTE: On vehicles with automatic overdrive transmission, if speed drops 5 MPH less than set speed, cruise control unit cancels or prevents OD transmission function. When vehicle speed returns to within 2 MPH of set speed for at least 20 seconds, OD transmission function is restored.