Speed Control System

The speed control system consists of:

• Speed control servo (9C735).
• Speed control actuator cable (9A825).
• Vehicle speed sensor (VSS) (9E731) (Ranger only).
• Operator controls, located on the steering wheel (3600).
• Speed control actuator switch (9D743).
• Stoplight switch.
• Deactivator switch.
• Deactivator switch located on the brake master cylinder (2140) (Ranger only).
• Deactivator switch located on the brake pedal (2455) (Aerostar only).
• Instrument cluster indicator light (Ranger only).

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

Speed Control Actuator Switch Assembly

• Is mounted in the steering wheel.

It consists of:

• LH buttons (ON, OFF)
• RH buttons (RSM, SET/ACCEL, COAST)
• Necessary wiring

Speed Control Indicator Light (Ranger Only)

• Is located in the instrument cluster (10849) above the speedometer.
• Comes on when speed control is ON and speed is set.
• Light goes out when brakes are applied or system is turned OFF.
• When ignition key is turned to ON position, light comes on briefly as part of cluster display self test.
• Light does not indicate problem with speed control system.

Speed Control Servo

• Is mounted on the right front fender on Ranger, and is located on the left side of the engine compartment on Aerostar.
• Is connected to the throttle linkage with a speed control actuator cable.
• Electronics are integrated into the speed control servo, eliminating the need for any other speed control electronic modules in the vehicle.

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.

Air Bag Sliding Contact

• Is located behind the center of steering wheel.
• Transfers electrical signals from the steering column wiring to the following components.
• Driver side air bag module (043B13)
• Steering wheel horn switch
• Speed control actuator switch assembly

Vehicle Speed Sensor (VSS), (Ranger Only)

• Is mounted to the transmission on Ranger, and mounted on the rear axle assembly on Aerostar vehicles.
• On Ranger it is a magnetic pickup driven by a gear which is driven by the transmission.
• On Aerostar, the signal is routed directly to the anti-lock brake control module (2B373) and the programmable electronic speedometer/odometer module (PSOM).
• Sends a signal to the speed control servo proportional to vehicle speed.

Deactivator Switch

• Under increased brake pedal motion, the deactivator switch will open and remove power from the speed control servo, releasing the throttle from servo control.
• On Aerostar, the switch is located on the brake pedal. On Ranger, it is located on the brake master cylinder.

System Activation

To operate the speed control system, the engine (6007) must be running and the vehicle speed must be greater than 48 km/h (30 mph). Under these conditions, the system is activated by pressing the ON switch in the steering wheel. Then, the operator must depress and release the SET/ACCEL switch. This will result in the current speed being maintained until a new speed is set, the brake pedal is depressed, or the OFF switch is depressed. Only one switch button should be depressed at a time because the speed control system will accept only one command at a time.

Increasing Set Speed

Accel

A continuous depression of the SET/ACCEL switch will cause a smooth increase in vehicle speed. Upon release of the SET/ACCEL switch the new vehicle speed will be maintained.

The vehicle speed can be manually increased at any time by depressing the accelerator pedal and shaft (9725) until the higher speed is reached and stabilized, then depressing and releasing the SET/ACCEL switch.

Tap-Up

Current vehicle set speed may be increased 1.6 km/h (1 mph) by a momentary tap of the SET/ACCEL switch. Multiple taps of the SET/ACCEL switch will cause vehicle speed to increase in increments of 1.6 km/h (1 mph). For example, if currently set at 80 km/h (50 mph) then five taps will increase vehicle speed and set it at 89 km/h (55 mph).

Decreasing Set Speed

Coast

A continuous depression of the COAST switch will cause a smooth decrease in vehicle speed. Upon release of the COAST switch the new vehicle speed will be maintained.

The vehicle speed can be manually decreased at any time by momentarily depressing the brake pedal until the lower speed is reached and stabilized, then depressing and releasing the SET/ACCEL switch.

If vehicle speed is reduced below 48 km/h (30 mph) then the driver must manually increase the speed to over 48 km/h (30 mph) and reset the system.

Tap-Down

Current vehicle set speed may be decreased 1.6 km/h (1 mph) by a momentary tap of the COAST switch. Multiple taps of the COAST switch will cause vehicle speed to decrease in increments of 1.6 km/h (1 mph). For example, if currently set at 89 km/h (55 mph) then five taps will decrease vehicle speed and set it at 80 km/h (50 mph).

Resume

When the speed control system is disabled by pressing the brake pedal, the previous set speed may be re-established by momentarily depressing the RSM switch. The resume feature will not function if the system has been turned off with the OFF switch or if the ignition switch (11572) is turned off. If the vehicle speed has dropped below 48 km/h (30 mph) then RESUME will not function until the vehicle speed becomes greater than 48 km/h (30 mph).

Contact Assembly (Clockspring)

The contact assembly provides electrical interface between the steering column tube (3514) and the control switches in the steering wheel.