How to Align Garage Door Sensors in 10 Minutes

Your garage door opens fine, but it refuses to close. You hold the wall button and it closes, but from the remote it reverses and the opener light blinks. That pattern points at the safety sensors, the two small photo eyes near the floor of the tracks, and most of the time you can fix it yourself in a few minutes.

What the sensors do

Since 1993 every opener has two infrared eyes about six inches off the floor. One sends a beam, the other receives it. If anything blocks or misaligns that beam while the door is closing, the door reverses to avoid closing on a person, a pet or a bumper. When the beam is broken all the time, the door refuses to close from the remote at all.

The 10 minute alignment

1. Check the lights first. Each sensor has a small LED. Typically one is a steady sending light and the other is the receiving light. A dark or flickering receiver LED means the beam is not landing.
2. Clear the path. A broom handle, a trash can wheel, spider webs or a leaf on the lens are the most common culprits. Wipe both lenses with a soft dry cloth.
3. Look for the bent bracket. Sensors live at bumper height, and a light tap from a car or a bin knocks them out of aim. Compare the two: they should face each other squarely.
4. Loosen and re-aim. Loosen the wing nut or screw on the misaligned sensor, point it straight at its partner, and hold it while the LED comes on steady. Tighten while watching the light stay solid.
5. Check the wiring run. Follow the thin wires up the wall and ceiling. A staple that cut the insulation or a chewed wire causes the same symptoms and no amount of aiming fixes it.
6. Test. Close the door from the remote. Then test the reversal by waving a broom through the beam while it closes. It must reverse immediately.

LiftMaster and Chamberlain sensor alignment: what the yellow and green lights mean

LiftMaster, Chamberlain and Craftsman openers share the same sensor design. The sending eye has an amber or yellow LED that stays lit whenever the sensor has power. The receiving eye has a green LED that is steady only when the beam is landing. A green light that is off, dim or flickering is the alignment signal: loosen the wing nut on the receiving sensor, swing it slowly toward its partner until the green light holds steady, then tighten without letting it drift. If the yellow light is also off, the problem is power or wiring, not alignment. On these openers a misaligned sensor also makes the opener light flash ten times when you press the remote, which is the opener telling you the safety sensors are blocked or out of line.

Genie sensor alignment: the red and green lights

Genie and Overhead Door openers use the Safe T Beam system. The sending eye has a red LED and the receiving eye a green LED, and both steady means aligned. A blinking red light means the beam is blocked or the eyes are out of line. Re-aim the receiving eye the same way: loosen, swing toward the partner until the green light holds, then tighten. If both lights stay dark, check the wire run before replacing anything. If both lights are solid and the door still reverses, that is the point to call for garage door opener repair rather than keep adjusting.

When it is not the sensors

If the LEDs are steady and aligned but the door still will not close, the problem moves up the chain: the logic board, the travel limits or the door itself binding in the tracks. That is where we come in. Our garage door opener repair techs carry boards, sensors and remotes for LiftMaster, Chamberlain, Genie and the other major brands, and our garage door repair team handles the mechanical side the same day. Before buying new sensors, read the common garage door sensor repair mistakes we see on service calls. The service call and the most common repair prices are listed in our garage door repair cost guide for Boca Raton.