

Openers · New Tecumseth
Photo-Eye Sensor Alignment or Replacement
On bright mornings the door will not close, then by lunchtime it behaves itself.
In plain words
Two small sensors face each other across the doorway: one sends an infrared beam, the other receives it. While the beam lands on the receiver, the opener will close the door; the moment anything interrupts it, the door stops and returns to open. Every sensor call comes down to why the receiver has lost the beam: an object, a bent bracket, a dirty or frosted lens, sun in the receiving eye, a broken wire or a tired sensor. The technician works through those in order, fixes the one that applies, and shows you the steady indicator lights that mean the pair is talking again.
How the visit goesThe small light on one of the sensors near the floor has gone dark, or it flickers when someone walks past the track. The other one glows steadily. The door refuses to close from the car.
Photo-Eye Sensor Alignment or Replacement
How the visit goes


Clearing and walking the beam
Before anything is adjusted, the technician clears the strip of floor between the two sensors and looks along the beam line at sensor height. Things that break a beam are rarely dramatic: the corner of a recycling bin, a hose left coiled by the wall, a bag of salt, leaves blown in under the door, a cobweb bridging a lens, a new weatherstrip or track shoe that sits a little proud. Snow and ice piled inside the door in winter count too. With the path clean, the door is tried again, because a fair share of sensor calls end right here, with a lesson about where things can and cannot sit.
Straightening or replacing the brackets
A bent bracket is straightened where the metal allows and replaced where it has cracked or rusted through. New brackets are chosen to suit the mounting: a track-mounted clip that rides the vertical rail, or a right-angle bracket anchored to the wall or the concrete where the track sits too far back. Fasteners that vibrated loose are replaced with the right carriage bolts and wing nuts rather than reused. Where a bracket has been sitting in salt slush every winter, it is set a touch higher within the permitted range and the mounting is sealed against the wall so water stops running behind it.
Two lights to glance at
You leave knowing what normal looks like at the floor. Most sensor pairs carry a small indicator on each side, often in different colours for sender and receiver, though some older pairs light only the receiver; the model's own chart tells you what steady and flickering mean. A dark or flickering light on the receiving side means the beam has been lost, usually because a bracket was bumped or something is in the path, and two dark lights mean the pair has lost power along the wire. A glance at those lights before calling anyone tells you most of what the technician would look at first, and often the fix is moving whatever is leaning on the bracket.
Photo-Eye Sensor Alignment or Replacement
In the van
2x4 test block
Receiving-eye sun shade
Matched photo-eye sensor pair
Protective wire channel
Wall or floor angle brackets

Photo-Eye Sensor Alignment or Replacement
What affects the quote
Number of doors
Each opener has its own sensor pair and wire run, so a double garage with two doors is two sets of checks, two possible pairs and two rounds of testing, quoted per door.
Opener make and generation
Sensor pairs are matched to the opener family, and some models take a kit with brackets and wire while others take sensors alone. The head unit label sets which pair is needed and how it is priced.
Force and travel adjustment alongside
If the reversing turns out to involve a travel limit set long or a force setting made in summer, adjusting and re-testing those settings is included as a small extra step.
What to have ready
- How many doors and openers are there?
- Is there frost, snow, slush or salt around the sensors in winter?
- Are there sensors at the floor on both sides, or are they missing or mounted up beside the motor?
Photo-Eye Sensor Alignment or Replacement: questions
QuestionsWill my phone app or hub still work after the sensors are changed?
Yes. The sensors are wired to the head unit, and the app or hub simply talks to that unit, so nothing about the connection changes. What you will notice is the fault code clearing: apps that reported the sensors as obstructed or not aligned show the door as ready to close again. If an app or hub still holds an old code after the work, refreshing it or cycling the door from the app once clears it.
What happens during the visit, in order?
Questions first: what the door does, when it began, what changed. Then the beam path is cleared, the sensor lights are read, the opener's flash code is counted, and the brackets and heights are measured. If the signs point to the circuit, the wire is traced and tested with a meter. The cause is fixed, whether that is alignment, brackets, wire, a shade or a new pair, and the visit closes with the beam test and the contact reversal test.
Why does it only misbehave on sunny mornings?
Sunlight reaching into the receiving lens can overwhelm the infrared beam from the sending sensor, so for an hour or two the opener acts as if the path is blocked. Garages that face the low sun in winter see it most. The cure is to exchange the two sensors' positions so the receiver no longer looks toward the light, or to fit a small shade over the receiving lens. Once that is done the time of day stops mattering.
