Garage Door Won't Close? Safety Sensor Troubleshooting Guide (Austin)

Published June 4, 2026  ·  6 min read  ·  Troubleshooting

If your door starts closing then reverses — or the opener light blinks — the safety sensors are almost always the culprit. Here's how to diagnose and fix it.

When a garage door starts to close and then reverses back up — often with the opener light blinking — the problem is almost always the photo-eye safety sensors near the floor. This is a federally required safety feature, and it's usually a quick fix. Here's how to troubleshoot it before you call for service.

Why does my garage door reverse before it closes?

Federal law requires every automatic garage door to have two photo-eye sensors mounted about six inches above the floor on each side. They project an invisible beam across the opening. If anything breaks that beam — or the sensors are misaligned, dirty, or unplugged — the opener refuses to close and reverses as a safety measure.

How do I fix garage door sensors that won't let the door close?

Work through these steps in order — most Austin homeowners solve it at step 1 or 2:

• Clear the path — remove any boxes, trash cans, or objects breaking the beam.
• Wipe the lenses — clean both sensor eyes with a soft dry cloth; dust, cobwebs, and pollen are common culprits in Austin.
• Check the indicator lights — both sensors should glow steadily. A blinking or dark light means they're misaligned or have lost power.
• Realign the sensors — gently adjust each bracket until both lights are solid green/amber and pointed straight at each other.
• Inspect the wiring — look for chewed, pinched, or loose wires at the sensors and the opener motor.
• Rule out sun glare — direct afternoon Texas sun hitting a lens can blind a sensor; a small sun shield or sensor hood fixes it.

Why is my garage door opener light blinking?

A blinking opener light (often 10 flashes on LiftMaster/Chamberlain units) is the opener telling you the safety sensors are obstructed, misaligned, or disconnected. Once the sensors see each other again, the blinking stops and the door closes normally.

When should I call a professional?

Call a technician if the lights stay dark after cleaning and realignment, if wiring is damaged, or if the door still reverses with clean, aligned sensors — that can point to a failing logic board or limit setting. Sensor service in Austin typically runs $95–$189.

Still won't close? Call Titanium Garage Door at (512) 915-7755 for same-day sensor and opener service across the Greater Austin area — no after-hours surcharge, ever.