installed my tailwind iq3 but now my garage door won't close all the way, it reverses about an inch up.

Diagnosis

The issue where your garage door reverses approximately one inch from the floor is almost always caused by a "false trigger" of the infrared safety sensors (photo-eyes). The Tailwind iQ3 acts as a smart bridge to your existing opener; while it doesn't replace the safety sensors, it often exposes latent sensitivity issues in the existing wiring or alignment that your old, slower controller might have ignored. When the door reaches the bottom of its travel, the slight vibration of the door hitting the seal can cause a momentary misalignment or a "flicker" in the sensor beam, triggering the safety reverse mechanism.

This happens because the iQ3 processes signals with higher precision and faster response times. If the sensors are tilted even a few degrees, or if the lenses are clouded with dust, the beam strength is weakened. As the door descends, the physical shift in the garage environment (air movement or vibration) breaks that weak connection, telling the iQ3 that an object is in the path, forcing the door to reverse for safety. You can confirm this by observing the LED lights on the sensors; if one is flickering or dim right as the door reaches the bottom, the alignment is the culprit.

How to Fix It

To resolve this, you must perform a precision alignment and cleaning of the infrared sensors. Follow these exact steps:

1. Clean the Optics: Use a clean, dry microfiber cloth to wipe the lenses of both the sending and receiving sensors. Even a thin layer of garage dust or a single spiderweb can refract the IR beam, reducing the signal strength.
2. Verify the Beam Path: Stand at the sensor that has a steady light (usually the sender) and look across to the receiver. Ensure there are no boxes, trash cans, or stored items within 6 inches of the beam's path.
3. Adjust the Angle: Loosen the mounting screws on the sensor brackets slightly. The sensors must be perfectly parallel. If the receiver is tilted upward or downward, the beam will "clip" the edge of the sensor housing as the door vibrates upon closing.
4. The "Squeeze" Test: Ensure the sensors are mounted no more than 6 inches off the ground. If they are mounted too high, the door may not trigger the reverse, but if they are too low and touching the floor, the door's descent can push them out of alignment.
5. Tighten and Test: Tighten the brackets firmly so they cannot vibrate. Trigger the door via the Tailwind app and watch the sensors closely as the door hits the floor. If the light on the receiving sensor flickers at the moment of impact, nudge the bracket 1-2mm and test again.

If That Didn't Work

• Check for Wire Fatigue: Inspect the low-voltage bell wire running from the sensors to the opener. If the wire is pinched or frayed, the vibration of the door closing can cause a momentary short, which the iQ3 interprets as a sensor trip. Replace any nicked wiring with 22-gauge stranded wire.
• Adjust Down-Travel Limit: Your opener's internal limit switch may be set too low, forcing the door to press too hard into the concrete. This creates a "bounce" effect that triggers the sensors. Use a screwdriver to turn the "Down" limit screw on your motor unit counter-clockwise by a quarter turn to reduce the closing pressure.
• Inspect the Door Tracks: If the door binds or hitches slightly at the bottom, the motor senses an increase in amperage (force). The iQ3 may interpret this resistance as an obstruction. Lubricate the tracks and rollers with a silicone-based garage door spray to ensure a smooth final descent.
• Check for Sunlight Interference: If this only happens during certain times of the day, direct sunlight may be "blinding" the receiver. Install a small piece of cardboard or a plastic shield (a "sun hood") over the receiving sensor to block overhead glare.

Heads Up

• Never Bypass Sensors: Do not attempt to jump the sensor wires to disable the safety feature; this is a critical safety risk and can lead to property damage or injury.
• Avoid WD-40: Do not use standard WD-40 on your tracks; it attracts dust which will eventually block your sensors. Use a dedicated lithium or silicone lubricant.
• Firmware Updates: Ensure your Tailwind iQ3 firmware is up to date via the app, as updates often include refinements to how the controller handles sensor signal noise.
• Vibration Check: If you have a heavy-duty rubber seal at the bottom of the door, ensure it isn't so thick that it pushes the door back up, mimicking a sensor reverse.