Vacuum Operated Speed Control System
Speed Control SystemThe vehicle speed control system consists of:
- Speed control actuator
- Speed control servo
- Vehicle speed sensor
- Stoplight switch
- Speed control dump valve
- Horn relay and bracket
- Speed control vacuum reservoir
- Speed control vacuum valve
- Speed control amplifier
- Necessary wires and vacuum hoses
Speed Control Servo:
- Is mounted in the engine compartment as shown in the illustrations and is connected to the throttle linkage with a speed control actuator.
- The speed control servo is connected to the speed control vacuum reservoir and to vacuum outlet manifold through the speed control vacuum valve as shown in the illustrations.
Speed Control Amplifier:
- Is located left hand side of the instrument panel behind the lamp dimmer potentiometer.
Speed Control Actuator Switch Assembly:
- Is mounted in the steering wheel. It consists of:
- LH buttons (ON, OFF).
- RH buttons (RESUME, SET,/ACCEL, COAST).
- Necessary wiring.
Vehicle Speed Sensor (VSS):
- Is mounted to the transaxle.
- Is a magnetic pickup driven by a gear which is driven by the transaxle.
- The VSS signal sent to speed control amplifier is proportional to vehicle speed.
Air Bag Sliding Contact:
- Is located at the center of steering wheel. It transfers electrical signals from the steering column wiring to:
- Driver side air bag module.
- Horn blow switch
- Speed control actuator switch.
Stoplight Switch:
- Is a normally open switch and closes when brake pedal is applied.
- Then an electrical signal is sent to the speed control amplifier and speed control system is disengaged.
Speed Control Dump Valve:
- Provides a redundant safety feature in the system
- Normally, when the brake pedal is applied, an electrical signal from the stoplamps to the speed control amplifier turns off the system.
- In addition, the speed control dump valve will mechanically release the vacuum in the speed control servo when the brake pedal is applied.
- This releases the throttle independently of the speed control amplifier.
Speed Control Vacuum Valve:
- Is used to apply either manifold vacuum or reservoir vacuum, whichever is greater to the speed control servo.
- The speed control servo is connected to the vacuum outlet manifold and to speed control vacuum reservoir through speed control vacuum valve.
Speed Control Vacuum Reservoir:
- Speed control vacuum reservoir is located in the engine compartment on the LH side and is attached to the A-pillar.
- The purpose of speed control vacuum reservoir is to provide supplemental vacuum source for the speed control system.
- Speed control vacuum reservoir is connected to speed control servo through the speed control vacuum valve and vacuum hoses.