Sound familiar?Peninsular Park
- 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.

The sensors are only as good as the thin two-conductor wire that links them to the opener. It runs from the low-voltage terminals on the head unit along the ceiling and down each wall to the floor, stapled as it goes, and it is easily pierced, cut during renovations, chewed, or pulled loose at the terminals. When both sensor lights are dark, or the opener's code says the circuit is open or reversed, the technician tests the run end to end, repairs the damaged section or replaces the whole run, checks polarity at the terminals, and clips the new wire clear of the track.
Sound familiar?Peninsular Park
Photo-Eye Sensor Alignment or Replacement · Peninsular Park

Scene 1
The two sensors have to sit at the same height, level, and facing each other squarely, no higher than about 15 cm (6 in) above the floor so the beam catches a small child or a pet. The technician measures both sides, because a bracket that has slipped a couple of centimetres down a track leg is enough to lose the beam. Each bracket is checked for bends from a bumper or a bin, for loose carriage bolts or wing nuts, and for rust where salt slush has sat against it for winters on end. A bracket screwed to a wall or the floor is checked for anchors that have worked loose.
Scene 2
No sensor job is finished on a steady light alone. The door is closed from the wall control and from a remote, and while it is on its way down an object is passed through the beam; the door must stop and return to fully open. Then a 2x4 is laid flat on the floor under the centre of the door and the door is closed onto it; it must reverse on contact. Both are repeated, the opener's diagnostic light is confirmed clear, and any app or hub reporting a sensor code is refreshed. The customer watches the tests so the normal behaviour is seen, not described.
Scene 3
You have a short written note of what was done: the opener make and model, what the diagnostic code and the sensor lights showed on arrival, whether the fault was alignment, wiring, sun or a worn sensor, what was replaced and where the new parts sit. It records the height the sensors were set at and that both tests were passed with you watching. That note is useful for a home inspection, for the next technician, and for you, because it shows what normal looks like on this door so a future change is easy to describe over the phone.
What shapes the quoteInnisfil Garage Door Co.
FeesSame any hour
Use the door in a way that keeps you in control. If the opener closes only while the wall button is held, do that only while you can see the whole doorway and nobody is near it. Otherwise close the door first if you can, then move it by hand with the manual release, and get help if it feels heavy or binds. Keep children and pets clear during any test. A door that reverses is being cautious on your behalf.
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.
Alignment, cleaning and a bracket adjustment are done inside an hour on most doors, including the two tests at the end. Replacing the pair adds a little for wiring and setup. Re-running the wire all the way from the motor to both sensors is the part that stretches a visit, especially where the wire is behind a finished ceiling or the garage is full. Having the floor by the door clear before arrival helps.
SimcoeOntario
Photo-Eye Sensor Alignment or Replacement · Innisfil, Bell Ewart, Big Bay Point, Cedar Harbour, Cookstown, Innisfil Park, Killarney Beach, Leonards Beach, Nantyr Park, Stroud, Alcona, Alderslea, Bear Point, Belle Air Beach, Big Cedar Point, Cedar Mount, Churchill, Crescent Harbour, De Grassi Point, Glenwood Beach, Lefroy, Mooselanka Beach, Sandy Cove, Tent City
Every square is one home in a hundred.
On-site assessment
Since shelving went up along the garage wall, the door will not close and both sensor lights are dead.
(249) 371-0023, open 24/7.
On-site assessment preferred · (249) 371-0023, open 24/7