Can direct sunlight interrupt the sensor, preventing the door from going all the way down? At night, early mornings or on overcast days my garage door goes up and down with no problem. However, when the sun is out the door will go down partially then back up. What can cause this?

  • When this improper reversal occurs is it always at the same door position or does it vary? I had some grass and cobwebs on the bottom of my door cause reversal when the grass passed through the beam to the electric eye. Absent this it does seem possible that stray sunlight could cause problems. One test for this might be to temporarily mount a tube (paper towel cardboard tube or piece of landscape drain) so as to shield the detector from stray light. See if the door works with this when it doesn't without. Maybe realign the source and detector, but I admit that I don't know how to do tthis. Feb 19, 2017 at 20:15
  • I suppose that at the time of brightest sunlight on the detector and it's reversing, you could shield the sensor with a large object outside the door and see if this has an effect. Feb 19, 2017 at 20:18
  • 2
    I recently installed a Chamberlain opener, and the instructions clearly recommended putting the sensor on the side of the door that would best avoid direct sunlight. Possibly you could swap sides with sender/receiver. Feb 19, 2017 at 20:53
  • What is the procedure for optimizing the alignment of the source and sensor? Can one put a DC voltmeter on the output of the sensor and then adjust the source for maximum signal? Feb 19, 2017 at 21:51
  • 1
    Most of the sensor are basically a switch triggered by light 1064nm being the most common wavelength. I have seen sun light and even a full moon cause the safety to reverse. Adding 1" of black tubing / hose on the reciever will help reduce stray light problems. If not labeled the transmitter or emitter usually has 2 wire connections and receiver has 3 connections (not always but many are wired this way.
    – Ed Beal
    Feb 19, 2017 at 23:37

2 Answers 2


My Genie suffered the same issue, sunlight "blinding" the system.

After reading all the "fixes", it occurred to me that the one simple remedy would be to simply reverse the devices, putting the receiver pointing away from the sunlight instead of into it.

The opener doesn't care which way it's laid out; it's totally arbitrary, at the whim of the installer.

The wiring on the Genie is very simple, with two leads to each device. This can be done in either of two ways: "home runs", (a pair of leads to each device), or a "loop", (one lead going to one device, then looping over to the other one). Both circuits are electronically the same. The red wire connects to the white with black stripe and the white wire connects to the white-only wire.

It took ten minutes to do, and I didn't have to build any boxes or use any toilet paper tubes. Hope this helps.


Your garage door opener is most likely radio-based. But the transmitters are very low power. It is quite possible for atmospherics to affect radio waves.

Sometimes you can build a metal box around the receiver which will make it receive signals from predictable directions.

  • The problem is with the safety sensors at the door's closed position. Feb 20, 2017 at 20:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.