Cruise control is a speed control system that maintains a desired vehicle speed under normal driving conditions. However, ascending or descending steep grades may cause variations in the selected speeds. On these vehicles, the speed control system is electrically controlled and vacuum operated. The electronic control is integrated in the Powertrain Control Module (PCM), located in the engine compartment.
The main parts of the cruise control system are the functional control switches, speed control servo, servo cable, PCM, vacuum reservoir and the release switches, including the dual function brake light switch.
The cruise control module assembly contains a low speed limit, which will prevent system engagement below 30 mph (50 km/h). The module is controlled by the functional switches, which are located on the steering wheel.
The cruise control can be manually disengaged by stepping on the brake pedal, depressing the OFF switch or the CANCEL switch. When this occurs, the cruise control system is electrically disengaged and the throttle is returned to the idle position.