Cruise Control: Description and Operation
The speed control system consists of the following:^ speed control servo
^ speed control cable
^ Vehicle Speed Sensor (VSS)
^ horn relay and bracket
^ speed control actuator switch
^ Brake Pedal Position (BPP) switch
^ deactivator switch
^ clutch pedal position switch (manual transmission only)
The system operates independently of engine vacuum; therefore no vacuum lines are required.
The speed control amplifier:
^ is mounted on the LH hinge pillar.
^ is connected to the throttle linkage with a speed control cable.
^ integrates system electronics, eliminating the need for any other speed control electronic modules in the vehicle.
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 vehicle speed sensor (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 brake pedal position (BPP) 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 clutch pedal position switch is used in series with the brake ON/OFF switch on vehicles with manual transmissions.
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.
^ with brake pedal travel, 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.