Cruise Control: Description and Operation

The speed control system consists of the following:
- Speed control servo
- Speed control actuator cable
- Vehicle Speed Sensor (VSS)
- Horn relay and bracket
- Speed control actuator switch
- Stoplight switch
- Deactivator switch
- Brake pressure control valve
- Air bag sliding contact

The system operates independently of engine vacuum, therefore no vacuum lines are required.

The speed control servo:
- Is mounted under the LH front fender, forward of the wheel.
- Connects to the throttle linkage with a speed control cable.
- Integrates system electronics, eliminating the need for any other speed control electronic modules.







The speed control actuator switch assembly is mounted in the steering wheel. It consists of:
- LH switches (ON, OFF).
- RH switches (RESUME, SET, ACCEL, COAST).
- Necessary wiring.

The VSS:
- Is mounted to the transmission.
- Is a magnetic pickup driven by a gear which is driven by the transmission.
- Sends a signal to the speed control servo proportional to vehicle speed.

The air bag sliding contact:
- Is located at the center of steering wheel.
- Transfers electrical signals from the steering column wiring to the following components:
- Driver side air bag module.
- Horn blow switch.
- Speed control actuator switch.

The stoplight switch:
- Is a normally open switch that closes when the brake pedal is applied.
- Sends an electrical signal to the speed control servo when closed and disengages speed control system.
- Returns to its open position when the brake pedal is released.

The deactivator switch:
- Is a normally closed switch.
- Replaces the speed control dump valve as a redundant safety feature in the system.

Under normal conditions, when the brake pedal is applied, an electrical (brake ON/OFF) signal from the stop lamp circuit to the speed control servo will disengage the system.

Under increased brake pedal efforts (36-67 N [8-15 lbs] engine running), the deactivator switch will open and remove power to the speed control servo, releasing the throttle from servo control.

The deactivator switch is located on the brake pedal support assembly.