Mighty Mule Driveway Vehicle Sensor FM140, 100 ft Cable (Black) — 12 ft Detection, Wired Exit

The Mighty Mule FM140 100 ft. driveway vehicle sensor is a buried magnetic probe that detects passing vehicles and triggers your automatic gate to open for free exit without a remote.

This wired driveway sensor is designed to give vehicles a hands-free exit by sensing the metal mass of a car, truck, motorcycle, or ATV as it crosses a 12-foot detection field. The FM140 connects directly to the gate opener control box and includes 100 feet of cable to be trenched alongside your driveway. It is intended for in-property installation so visitors can leave without using a remote or keypad, simplifying egress and reducing traffic jams at gated entrances.

How does this sensor detect a vehicle and open my gate?

The FM140 uses a buried magnetic probe that senses changes in nearby metal mass when a vehicle passes over or near it. When the probe detects a vehicle within its roughly 12-foot magnetic field, it sends a signal through the wired cable to the gate opener to initiate an open command. Detection is fast and designed specifically for exit-only operation, helping vehicles leave smoothly without manual input.

• Direct-burial probe senses changes in metal mass.
• Approximately 12 ft. detection radius for reliable triggers.
• Hardwired connection to the gate opener control box for secure signaling.

Where and how should I install the FM140 for best performance?

Install the probe inside your property, alongside the driveway, trenched up to 12 inches deep and placed next to the drive where vehicles will pass. The unit ships with 100 feet of cable, allowing flexible positioning between 3 and 100 feet from the gate; locate it so cars cross through the probe’s detection field as they depart. Follow local codes for underground wiring and use conduit where needed to protect the cable from damage.

• Buried next to driveway, trench depth up to 12 inches recommended.
• 100 ft. cable supports placement 3–100 ft. from the opener control box.
• Position probe where departing vehicles will pass through the 12 ft. field.

Will the FM140 work with my gate setup and different vehicle types?

The FM140 is compatible with single and dual gate openers that accept a wired vehicle sensor input; it communicates through the gate opener’s control box. Its magnetic sensing detects a wide range of metallic vehicles, including cars, pickup trucks, motorcycles, ATVs, and other metal-bodied equipment. For installations where running wire isn’t possible, consider Mighty Mule’s wireless sensor alternatives.

• Works with single and dual gate systems that have a sensor input.
• Detects cars, trucks, motorcycles, ATVs and similar metal vehicles.
• Wired design for secure, interference-resistant operation; wireless option available separately.

What length options and accessories are available if I need a different cable run?

Mighty Mule offers multiple probe lengths so you can choose the cable length that matches your driveway layout. Besides the FM140 100 ft. model, 50 ft. and 150 ft. versions exist for shorter or longer runs. If you prefer to avoid trenching, a wireless driveway sensor is also available from the same product family.

• Available in 50 ft., 100 ft. (FM140), and 150 ft. versions for varied distances.
• Wireless Mighty Mule sensor sold separately for non-buried installations.
• Use conduit or protective tubing to extend cable life where needed.

Who is this for: The FM140 is ideal for homeowners, farm properties, and commercial sites that want a reliable, low-profile way to allow hands-free exits from a gated driveway. Choose this probe if you can trench a cable run and need a rugged wired solution compatible with single or dual gate openers. If you need wireless convenience or a different cable distance, look at the alternate FM series lengths or the wireless model.