LiftMaster Garage Door Opener Opens But Won’t Close

By Todd Fratzel on Garages

LiftMaster Garage Door Opener Won’t Close Door

I’ve been a huge fan of LiftMaster Garage Door Openers for years. I like them so much because they work very well and last a long time. So this winter when I started having trouble with my door opener I was a bit puzzled and frustrated. However, as you’ll learn below the solution to this problem was extremely easy to fix and something you should know for the future.

The Problem: The door would always open fine but then would have trouble closing. Sometimes it would close part way before stopping and reversing and other times it wouldn’t open at all. Another clue to the mystery was if you held the wall switch the door would completely close. However, the remote would not be able to close the door even if you held the button.

The Solution: Adjusting the Protector System® sensors fixed my problem and the door now operates correctly.

The Protector System® Safety Reversing Sensors

Years ago garage door openers were required to utilize safety sensors to prevent doors from closing on small children. LiftMaster uses the Protector System® which projects an invisible light beam across the door opening and automatically opens the door if something/someone crosses it’s path.

So at first I didn’t think the Protector System® was to blame. Each time the door was having trouble I’d get out of my truck and check to be sure the path between the sensors was all clear. Each time I’d discover nothing in the way so I figured the sensors were fine.

Adjusting Reversing Sensors

In order for the safety reversing sensors to work properly they must be aligned correctly. One of the sensors is a sending unit (shoots the light out) and the other is a receiver which ‘catches’ the light beam. The following comes from the User’s manual:


  • Plug in the opener. The indicator lights in both the sending and receiving eyes will glow steadily if wiring connections and alignment are correct.

The sending eye amber indicator light will glow regardless of alignment or obstruction. If the green indicator light in the receiving eye is off, dim, or flickering (and the invisible light beam path is not obstructed), alignment is required.

  • Loosen the sending eye wing nut and readjust, aiming directly at the receiving eye. Lock in place.
  • Loosen the receiving eye wing nut and adjust sensor until it receives the sender’s beam. When the green indicator light glows steadily, tighten the wing nut.

So there you have it. If your garage door opens ok but won’t close then it’s possible the safety reversing sensors are not correctly aligned. Don’t just assume that if the path is clear that the sensors are ok. This problem bugged me for several months. Hopefully after you read this you won’t have the same problem in the future.


About the author

Todd Fratzel

I'm full time builder for a large construction company in New Hampshire. I run their design-build division that specializes in custom homes, commercial design-build projects and sub-divisions. I'm also a licensed civil and structural engineer with extensive experience in civil and structural design and home construction. My hope is that I can share my experience in the home construction, home improvement and home renovation profession with other builders and home owners. I'm also the author of Tool Box Buzz and Today's Green Construction. Please feel free to contact me if you have any questions, suggestions or you'd like to inquire about advertising on this site.

All posts by Todd »

Not what you're looking for?

Search for more articles here. Enter keywords like, 'insulation' or 'kitchens' etc to find your topic.


  1. James says:

    Thanks for posting the alignment tips. You really saved the day.
    I bought my house about 6 years ago and the garage opener worked flawlessly until last week, when it stopped closing correctly.
    I figured it had to be the sensors but had absolutely no idea how to adjust them (eyeballing was doing nothing).


  2. Todd says:

    Thank You! Took 2 minutes to fix.

  3. Paul says:

    Thanks for the info. I had the same problem. I adjusted the force screws, which did not help. After reading the info you posted, I checked the indicator lights. One of them was disconnected. I reconnected the wire and it did the trick!!

  4. George says:

    I just did it and it worked – the problem was exactly as described and so was the solution! Thank you very much!

  5. Lorne says:

    Worked great, but watch for corrosion in the wire to the sensors.

Leave a comment

Be nice. Keep it clean. Stay on topic. No spam.

Copyright © 2009-2014 Front Steps Media, LLC. All Rights Reserved. Home Construction & Improvement™ is a Trademark of Front Steps Media, LLC.