If your garage door won't close or if it reverses after a few inches when you try to operate it, it could simply be an issue with the photo eyes (safety reversing sensors) at the bottom of the door. If this is the case, you can easily check out and fix this problem on your own without having to call in a professional.

These simple mechanisms play a vital role in the safety of your garage door. There are thousands of garage door-related injuries every year, many of which could be prevented by following some easy maintenance steps.

How do photo eyes work?

Photo eyes send a beam from one end of your door to the other. If an obstacle is in the beam’s path, the garage door won’t close. It might go down a few inches and then reverse, or it might not go down at all. If nothing is blocking the beam in your garage, it’s likely that your photo eyes are dirty, dusty, or out of alignment.

How do I fix this problem?

The first (and easiest) thing to check is whether your photo eyes are dirty. Wipe off the lenses with a soft cloth, make sure not to scratch them. Scratches can also cause the photo eyes to malfunction.

1. Look at the indicator lights in both of the photo eyes. They will glow steadily if wiring connections and alignment are correct. The sending eye (identified by an 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 is not obstructed, alignment is required.
2. Loosen the sending eye wing nut and readjust, aiming it directly at the receiving eye. Lock into place.
3. 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.

1. If the sending eye indicator light doesn’t glow steadily, check for
   1. Electric power to the opener
   2. A short in the white or white/black wires, especially at staples or opener connections
   3. Incorrect wiring between sensors and opener
   4. A broken wire
2. If the sending eye indicator light glows steadily, but the receiving eye indicator light does not, check
   1. Alignment
   2. An open wire to the receiving eye
3. If the receiving eye indicator light is dim, realign either sensor.

NOTE: When the invisible beam path is obstructed or misaligned while the door is closing, the door will reverse. If the door is already open, it will not close. The opener lights will blink 10 times.

Simple Tests You Can Perform to Test Your System Monthly

Photo Eye Test

1. Open the door.
2. Use your garage door opener or wall button to close the door again.
3. While it is beginning to close, wave an object in front of the beam to see if the door reverses when the beam is broken.
4. If the door does not reverse, let it close, and clean the photo eyes or adjust them if they need to be aligned.
5. Repeat the test. If it still doesn’t reverse, call a professional.

Reversing Mechanism Test

1. Open your door.
2. Place a piece of wood (such as a 2x4) on the ground underneath the door so the door will come into contact with it as it closes.
3. Use your opener to close the door. As it comes down and touches the wood, it should instantly reverse and open again.
4. If the door does not reverse, contact a professional to service it. 

Servicing Garage Doors in Des Moines

If you have tried troubleshooting your garage door on your own and it still isn’t working properly, call us at 515-963-0989 or message us here. WD Door proudly serves customers around Ankeny, Des Moines, and Ames. We fix, install, and provide garage door maintenance service for both commercial and residential garage doors throughout Central Iowa.