What Is A Photo Eye, And Is It Responsible For Your Garage Door Not Closing?

Your garage door helps keep your home secure and shields your car from the elements — it also plays a huge part in your home's curb appeal. But when it malfunctions, it can quickly turn into a nightmare. If your garage door suddenly won't close, you might have heard that it's caused by something called a photo eye. But what exactly is this, and how can it stop the door from closing?

A photo eye is a safety sensor installed at a maximum of 6 inches from the bottom of a garage door track. The system uses lasers to detect any obstructions in the door's path, like a child or a pet, and prevent it from closing on that obstruction. Every garage door opener installed in 1993 or later is federally required to have photo eye sensors that reverse the door when it comes into contact with an obstruction.

But while this sensor can help prevent injuries or damage, it can also malfunction and stop the door from closing when the path is clear. Understanding your garage door's photo eye sensors can help you troubleshoot effectively when your garage door won't close.

Misaligned photo eye sensors are one of the main reasons why your garage door isn't closing. Each garage door includes two sensors — one on each side of the door track. As your door moves up and down with daily use, the sensors can be knocked out of alignment, preventing the lasers from connecting and the door from shutting. If you can't solve this issue yourself, you may need to hire a pro to align your garage door sensors so the door can close properly.

Dirt can also affect the function of the photo eye sensors. Debris, like leaves, dust, or spiderwebs can block the path between the photo eye sensors so they can't connect. In turn, the sensors will assume there's an obstruction, and your garage door won't close. To remedy this, shut off the power and wipe the sensors with a clean cloth to remove any debris.

Photo eyes need electricity to function. The wires connecting the sensors to the power can get pulled or twisted if they're disturbed and they can become loose over time with normal wear and tear. Loose or disconnected wires can prevent the photo eye sensors from working, and your garage door may get stuck in the open position. Electrical repairs like this are best left to a professional.

The photo eye sensors aren't the only potential culprit if your door won't shut. The garage door tracks might be the problem. Check for signs of damage, like a bent section of track, that might be stopping the door from shutting. If the damage is minimal, you can try a DIY method to fix a garage door that's off-track.

Also, check that your garage door limit settings are correct. These settings let the motor know when it should stop moving — but if they're set incorrectly, they could cause your garage door to partially close or not open all the way. A garage door technician can check the door's limit settings and adjust them as needed.

Worn or broken garage door springs could also be the cause of the problem. The springs evenly distribute the weight of the garage door on both sides so it hangs straight. When the springs wear out or break, your garage door will be off-balance and hang unevenly — and it may not close all the way. Replacing garage door springs is another project best left to a professional.