Test your garage door safety sensors (monthly)
The photo-eye sensors six inches off the ground are the only thing stopping the door from closing on a kid, pet, or car.
What you'll learn
- Why UL 325 requires photo-eye sensors on every residential garage door opener (since 1993)
- How to read the LED status — one sensor sends (usually green), one receives (usually amber/red)
- The two-test routine: object-break test and reverse test
- Why dust, spider webs, and a 1/8-inch misalignment can stop a door from closing
Step by step
- Press the wall button to close the door.
- As it closes, wave a broom or a box into the beam path, six inches off the ground.
- The door should immediately reverse and reopen. If it keeps closing — stop and call a professional.
- Next, lay a 2x4 flat on the floor in the door opening. Close the door again.
- When the door hits the wood, it should reverse within 2 seconds.
- Check the LED status on both photo-eye sensors. Both should be solid, not blinking.
Safety note
If either sensor LED is blinking, they're misaligned. Loosen the bracket screw, adjust until both lights go solid, and tighten. If the LED won't light at all, the sensor itself has failed — it's a $95–$180 replacement.
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