Mighty Mule Driveway Vehicle Sensor FM140 — 100 ft Magnetic Probe, 12 ft Detection Zone, Hardwired Black

The Mighty Mule FM140 100 ft Driveway Vehicle Sensor is an underground magnetic probe that detects passing vehicles within a 12-foot sensing field to trigger automatic gate opening for exit without a remote. The FM140 is a hardwired, direct-burial vehicle sensor designed to add convenient, hands-free exit to compatible Mighty Mule automatic gate openers. It uses a buried wand and 100 feet of cable to sense the metal mass of cars, trucks, motorcycles, and other vehicles as they cross a 12-foot detection zone. Installed inside the property and wired to your gate control box, the sensor eliminates the need to press a remote when leaving and is compatible with both single and dual gate installations.

How does the FM140 detect vehicles and trigger the gate?

The FM140 senses changes in the local magnetic field produced by moving metal. When a vehicle moves through its 12-foot detection band, the probe sends a signal through its cable to the gate control, which then activates the opener to allow exit.

• 12-foot magnetic detection zone registers passing metal mass.
• Direct-burial probe buried near or alongside the driveway within 12 inches depth.
• Wires directly to the gate opener control box for immediate activation.
• Suitable for cars, trucks, ATVs and motorcycles that cross the field.

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

Position the buried wand on the inside of your property next to the driveway so exiting vehicles pass through the sensing band. Trenched installation keeps the 100-foot cable protected; bury the probe no deeper than about 12 inches and run the cable to your gate opener control panel.

• Probe depth: up to 12 inches underground for dependable detection.
• Cable length: 100 feet, allowing flexibility in probe placement 3–100 ft from the gate.
• Best practice: install on the exit side of the gate for free exit without a remote.
• Wiring: connect directly to the control box following manufacturer wiring diagram.

Will the FM140 work with my gate and what installation options are available?

The FM140 is compatible with Mighty Mule single and dual gate systems when the control board accepts a vehicle sensor input. It’s a DIY-friendly, wired option; alternate lengths and a wireless model exist if 100 feet or wired installation doesn’t suit your site.

• Compatible with many Mighty Mule automatic gate openers for exit activation.
• DIY installation possible for homeowners comfortable with trenching and basic wiring.
• Other wired lengths available: 50 ft (FM138) and 150 ft (FM141).
• Wireless alternative: Mighty Mule FM130 for no direct-burial wiring.

This sensor is ideal for property owners who want a simple, reliable way to exit without pressing a remote or stopping at the gate. If you have a gated driveway, a compatible Mighty Mule opener, and can trench a short run for the 100-foot cable, the FM140 adds convenient, automatic exit sensing for everyday vehicles without altering your gate hardware significantly. For sites that require a shorter or longer cable, or where trenching is impractical, consider the FM138, FM141, or the wireless FM130 alternative.

FAQ

Q: Can the FM140 be used with dual gate systems?

A: Yes. The FM140 works with both single and dual Mighty Mule gate openers when wired to the control box.

Q: How deep should the sensor probe be buried?

A: Bury the probe no more than 12 inches deep and run the 100-foot cable in a protected trench to the control panel.