When the safety sensors stop seeing each other, the opener refuses to close the door and the light often blinks. The fix is usually simple, and this guide walks you through it safely.
What the Sensors Do
Two small eyes sit near the floor on each side of the door. They send an invisible beam. If something breaks the beam, the door reverses or will not close.
Common Causes
| Symptom | Likely cause |
|---|---|
| Door will not close, light blinks | Beam blocked or misaligned |
| One sensor light off | Wiring or power problem |
| Works sometimes | Loose bracket or sunlight glare |
| Door reverses halfway | Dirty lens or misalignment |
Safe Fixes To Try
- Wipe both sensor lenses with a soft cloth.
- Clear anything in the beam path, like a box or snow.
- Check that both sensors point at each other and are about the same height.
- Gently tighten any loose brackets.
- Look for a pinched or loose wire at the sensors and opener.
When To Call a Technician
If realigning does not help, a wire or sensor may be damaged. See our garage door sensor repair or opener repair service. Related: common opener problems.
Frequently Asked Questions
Why is my garage door opener light blinking?
Blinking usually means the safety sensors are blocked or misaligned.
Can I bypass the sensors?
No. They are a safety feature and should be repaired, not bypassed.
Do sensors wear out?
They can fail over time or from damaged wiring.
Can sunlight affect sensors?
Strong direct sun can interfere. Shade or repositioning can help.