Cruise Control System Description

CAUTION: Do not use the cruise control on slippery roads, steeply graded roads, or in heavy traffic of heavy or varying volume. Failure to follow these CAUTIONS could possibly cause you to loose control of the vehicle and result in damage to the vehicle and personal injury.

The cruise control is a speed control system that maintains a desired vehicle speed under normal driving conditions. The cruise control allows the driver to maintain a constant speed of 25 mph (40 km/h) or higher without depressing the accelerator. Any steep grades up or down may cause variations in the selected speeds. The cruise control system performs the following functions:
^ Cruising
^ Coasting
^ Resuming Speed
^ Accelerating

The cruise control system mainly consists of the following components:
^ The cruise control actuator assembly
^ The Clutch Pedal Position (CPP) switch (manual transmission only)
^ The cruise control mode switch (RESUME/ACCEL, COAST/SET, and CANCEL)
^ The cruise control ON/OFF switch (CRUISE CTRL)
^ The Powertrain Control Module (PCM)
^ The transmission range switch (automatic transmission only)
^ The stoplamp switch
^ The Vehicle Speed Sensor (VSS) (at the speedometer)

The cruise control actuator allows the system to control and maintain the desired vehicle speed. The cruise control actuator assembly monitors the vehicle speed. The cruise control actuator assembly uses the necessary commands in order to maintain or vary the vehicle speed in response to the inputs from the cruise control switch.

When a command is received, the Direct Current (DC) servo motor inside the actuator turns a worm gear. The turning of the worm gear moves the accelerator cable in order to adjust the throttle angle. The DC servo motor and the worm gear connect mechanically only when a magnetic clutch, situated between the DC servo motor and the worm gear, energizes.

The cruise control disengages when the cruise control actuator receives a cancel signal from the following locations:
^ The stoplamp switch
^ The cruise control ON/OFF switch (CRUISE CTRL)
^ The cruise control mode switch (RESUME/ACCEL, COAST/SET, and CANCEL)
^ The transmission range switch (automatic transmission only)
^ The Clutch Pedal Position (CPP) switch (manual transmission only)

Upon receiving a cancel signal, the cruise control actuator assembly de-energizes the magnetic clutch. When the magnetic clutch de-energizes, the DC servo motor and the worm gear mechanically disconnect. The throttle returns to the idle position.