Principles of Operation
PRINCIPLES OF OPERATIONSpeed Control Actuator
The speed control actuator provides signals to the stepper motor. The actuator moves the throttle by means of an internal stepper motor/geartrain and an actuator cable. The powertrain control module (PCM) generates the vehicle speed signal that the speed control actuator compares to the set speed selected by the driver. If a discrepancy exists, the speed control actuator will adjust the throttle, correcting the vehicle speed.
The speed control actuator is mounted behind the LH headlamp. The speed control actuator contains the electronic module and the stepper motor and geartrain.
If the clutch pedal (manual transaxle only) or the brake pedal is applied, the speed control actuator deactivates the speed control. The speed control actuator will enter a stand-by mode.
Speed Control Switches
The speed control system is operated by a 5-function switch mounted on the steering wheel.
The switch functions are:
When the ON switch is pressed and the vehicle is travelling at a speed greater than 48 km/h (30 mph), the speed control actuator will accept speed inputs.
The SET/ACC switch is used to set or accelerate the vehicle at speeds above 48 km/h (30 mph). The switch can be used in 3 ways:
- Accelerate the vehicle with the accelerator pedal to the desired speed, then press and release the SET/ACC switch. The vehicle will maintain the desired speed.
- Press the SET/ACC switch and hold it down until the vehicle reaches the desired speed. When the switch is released, the speed is stored in the memory and used to maintain the vehicle speed.
- Press the SET/ACC switch repeatedly in order to increase the vehicle speed by increments of 1.6 km/h (1 mph).
The COAST switch is used to reduce the vehicle speed. The switch can be used in 2 ways:
- Press and hold the COAST switch down until the vehicle slows to the desired speed. When the switch is released, the speed is stored in the memory and used to maintain the vehicle speed.
- Press the COAST switch repeatedly to reduce the vehicle speed by increments of 1.6 km/h (1 mph).
Pressing the RES switch returns the vehicle to the set speed when the speed control is in stand-by mode and vehicle speed is greater than 48 km/h (30 mph).
Pressing the OFF switch deactivates the speed control system. The speed setting stored in memory is erased.
Stoplamp Switch
If the brake pedal is tapped lightly while the speed control system is active, the actuator receives an input from the stoplamp switch. This causes the speed control actuator to close the throttle and put the system into stand-by mode.
Speed Control Deactivator Switch
If the brake pedal is applied rapidly while the speed control system is active, the speed control actuator receives an input from the speed control deactivator switch. This causes the electromagnetic-actuated coupling to disconnect from the stepper motor and deactivate. This allows the cable and throttle to close under throttle return spring control. The system is put in stand-by mode.
Clutch Pedal Position (CPP) Switch (Manual Transaxle Only)
If the clutch pedal is applied while the speed control system is active, the speed control actuator receives an input from the CPP switch. This causes the speed control actuator to close the throttle and put the system into stand-by mode.