Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Speed Control Systems - Automatic: Description
Speed control system consists of an "ON-OFF" switch, a "SET-ACCEL" and "COAST" switch, a "RESUME" switch (Ford, Mercury, Fairmont, Zephyr, Mustang and Capri only), a servo assembly, a speed sensor, a vacuum dump valve (Ford, Mercury, Fairmont, Zephyr, Mustang and Capri only), an amplifier, a vacuum reservoir (all exc. Ford, Mercury, Fairmont, Zephyr, Mustang and Capri), a wiring harness and vacuum hoses to connect components.
The switches are located in steering wheel spokes. Servo assembly and vacuum reservoir (if equipped) are located in engine compartment. Amplifier assembly is located under instrument panel. Speed sensor is located in engine compartment on Continental Mark V, Lincoln Continental, Fairmont, Zephyr, Mustang and Capri and in passenger compartment on all other models.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.