Sound familiar?Southgate
- The call
- You press the remote, the door drops a few centimetres, then climbs straight back to the top while the opener light blinks. Nothing is under the door. It has done this every evening this week.

After a cold night the door stays open until the garage warms up. There is frost on the sensor lenses and a ridge of salty slush piled against the brackets where the snow blower was parked.
If your opener has no sensors at the floor, that alone does not date it, since a pair can be missing, removed or never reconnected; the technician identifies the model before deciding whether a pair can be restored or the operator itself needs replacing. The visit is still worth making: the technician tests contact reversal and sets out what a modern operator brings, including a matched sensor pair, force reversal and a monitored circuit that holds the door open until the beam clears. Where sensors are present but tucked up beside the motor, they are returned to the doorway where they belong.
Sound familiar?Southgate
Photo-Eye Sensor Alignment or Replacement · Southgate

Scene 1
A sensor that misbehaves on a timetable is usually being blinded rather than broken. The technician notes which way the door faces, where the low sun reaches the floor in the morning and late afternoon, and whether a receiving lens looks into that light or into a reflection off a parked car, a white wall or fresh snow. Lenses are checked for frost, condensation and a film of salt, common in an unheated garage. A hand cupped over the receiving eye while the light is watched is a simple test: if the indicator settles when the eye is shaded, the fix is a side swap or a small hood rather than new parts.
Scene 2
Damaged wire is dealt with in whole sections rather than patched at a single point. A pierced or chewed length is cut back to sound insulation and either spliced with proper connectors or, more often, replaced from the sensor to the nearest good junction. Where the run has failed in more than one place, a fresh two-conductor wire is stapled from the motor housing across the ceiling and down both sides of the opening, kept clear of the track, hinges and the door's travel. At the head unit the pair is landed on the correct low-voltage terminals with polarity confirmed, and the sensor lights are checked before anything is tidied.
Scene 3
The habit worth keeping takes about a minute. Once a month, with the door open, press close on the wall control and, as it moves down, pass a broom handle through the beam near the floor. The door should stop and climb back to fully open. Then lay a 2x4 flat under the middle of the door and close onto it; the door should touch it and reverse. If either test fails, stop using the opener; close the door first if it is not already closed, then use the manual release, and get help moving it by hand if it feels heavy or will not hold. A door that passes both tests is doing its job.
What shapes the quoteHockley Valley Garage Door Experts
FeesSame any hour
It can, in a few ways. Frost or condensation on a lens in an unheated garage dims the beam until it clears. The low winter sun reaches further across the floor and into a receiving eye. Old wire insulation cracks in the cold and shorts. Salt slush builds against brackets and corrodes them and the terminals over the years. Each of those has a straightforward remedy: cleaning, a shade or side swap, a fresh wire run, or brackets set above the slush line.
It is a built-in stopgap, not a repair. When the sensor circuit is not satisfied, many openers allow a close from the wall control only while the button is held, on the idea that a person standing there can see the doorway. Newer units drop that behaviour altogether and simply hold the door open. Either way the door is telling you the beam has failed, and a sensor visit puts remote closing back.
Two, and you are invited to watch. With the door closing, an object is passed through the beam and the door has to halt and climb back to the top. A 2x4 laid flat beneath the door's centre comes next; closing onto it must make the door back off on contact. The door is also run from the wall control and a remote, the opener's warning flashes are confirmed gone, and both sensor lights are shown steady.
GreyOntario
Photo-Eye Sensor Alignment or Replacement · Orangeville, Amaranth, East Garafraxa, Grand Valley, Melancthon, Mono, Shelburne, Starrview Acres
Every square is one home in a hundred.
On-site assessment
After a cold night the door stays open until the garage warms up.
(226) 917-2730, open 24/7.
On-site assessment preferred · (226) 917-2730, open 24/7