First, make sure the sensors are actually dead
Photo-eye sensors sit about six inches off the floor on each side of the opening and talk to each other with an infrared beam. When the beam breaks or the pair loses sync, the opener refuses to close and usually blinks its lights at you. Before paying anyone, check these in order:
- The LEDs. Both sensors should glow steadily (typically one green, one amber on LiftMaster and Chamberlain). A dark or flickering LED means power or alignment trouble, not necessarily a dead sensor.
- Alignment. The brackets bend if a rake handle or car tire nudges them. Loosen the wing nut, sight the lenses at each other until the LED steadies, retighten.
- Obstructions and glare. Cobwebs, a leaf, or low winter sun shining straight into a lens will break the beam. West-facing garages in Yukon and Mustang get the sun version every December afternoon.
- Wiring. Staples pull loose, and we have found plenty of mouse-chewed sensor wire in garages backing to greenbelts in Edmond and Norman.
If the LEDs light correctly and the door still will not close, the fault may be in the opener logic board instead, which is opener repair territory and a different conversation.
What replacement actually costs
Sensors are sold in matched pairs and must match your opener brand's protocol, so the quote depends on brand, wiring condition, and mounting work. A pro visit covers the parts, fresh wire runs if the old insulation is brittle, bracket mounting at the correct height, alignment and a full reversal test. We service every major brand, and since 1993 federal law (UL 325) has required these sensors on every opener sold, so there is no legal or safe way to "just bypass them," and any company offering to should not be in your garage.
When sensors point at a bigger decision
If your opener predates 1993 and has no sensors at all, replacement of the whole unit is the only responsible fix, and modern units are dramatically quieter and safer; our answer on LiftMaster installation pricing covers that math. Repeated sensor failures on a newer opener usually trace to voltage problems or water exposure at the floor line, both worth a professional look. Either way, the diagnosis costs nothing: estimates are free across the metro, 24/7, at (405) 247-0336, or book at affordabledoorco.com/book.