Cruise Control System

The Powertrain Control Module (PCM) controls ground circuit to vacuum and vent solenoids in speed control servo for controlling the cruise control system. When PCM completes the ground circuit to vacuum and vent solenoids in speed control servo, throttle is opened, and when ground circuits are open, throttle is closed. PCM balances the vacuum and vent solenoid operation to maintain the set vehicle speed. If a failure exists in the cruise control system, a Diagnostic Trouble Code (DTC) will be stored in the PCM.