Manual Transmission

OPERATION

System
The Speed Control Amplifier controls vacuum through the Modulating Valve to the Speed Control Servo Motor. The Servo Motor moves the throttle through the Actuator cable.

For the Speed Control System to operate, the engine must be running and the vehicle speed must be greater than 30 mph. Pressing the ON switch of the Speed Control Switch Assembly turns on the system.

Modes
Pressing and releasing SET/ACCEL or COAST sends a command to hold the present speed. This speed becomes the set speed. Using the Vehicle Speed Signal (VSS), the Speed Control Amplifier controls vacuum at the Servo Motor to keep the vehicle at the set speed.

Pressing and holding SET/ACCEL speeds up the car. The vehicle's speed increases while SET/ACCEL is depressed. Releasing SET/ACCEL gives the system a new set speed to maintain. Vehicle speed may also be increased by depressing the accelerator until the higher speed is reached, then pressing and releasing SET/ACCEL.

Pressing and holding COAST slows down the vehicle. The vehicle speed decreases while COAST is depressed. Releasing COAST gives the system a new set speed to maintain.

Pressing OFF turns off the system. The system is also turned off when the Ignition Switch is turned off. Depressing the brake pedal cancels the speed control. The Vacuum Dump Valve also operates when the brake pedal is depressed. This serves as a backup device to release the servo.

The Speed Control Amplifier monitors a ground reference input through the Clutch Pedal Position Switch, Stop Lamp bulb circuits, and the 81O (R/LG) wire. When the clutch pedal is depressed, the ground circuit is broken and the Speed Control System is cancelled.

When the system has been cancelled by depressing the brake or clutch pedal, the last set speed may be resumed by pressing RESUME. This feature will not work if OFF has been depressed or when vehicle speed is below 30 mph.