A door that opens fine but reverses on the way down — or refuses to move while the opener light blinks — is one of the most common calls we get. It's also the one most likely to have a fix you can do yourself before you pay anyone.
Every opener made since 1993 has two small sensors mounted about six inches off the floor on each side of the opening. They shoot an invisible beam across the doorway, and if anything interrupts it the door will not close. A bike tire, a bag of softener salt, a cord — or nothing at all, if a sensor got bumped out of alignment. One sensor light should be steady; if it's flickering or dark, loosen the wing nut, nudge the sensor until the light is solid, and tighten it back down.
Dust, cobwebs, and road-salt film cut the beam just as effectively as an obstruction. A dry cloth on both lenses takes ten seconds.
West-facing garages get an hour of low sun that can wash out the receiving sensor. If your door only misbehaves in the late afternoon, that's almost certainly the cause. A small sun shield over the receiver solves it permanently.
Stand inside with the door up and sight along both vertical tracks. Debris, a dropped tool, or a bent section will stop the door partway. Never force the door past an obstruction.
Openers have a force adjustment that can drift; set too sensitive, it reads normal friction as an obstruction. It's adjustable on the opener head — but it's also a safety setting, and set too aggressive the door won't reverse when it should. If the first four steps didn't fix it, this is where to stop and call.
If the door reverses at the same point every time, or slams instead of settling, the issue is balance or a worn cable rather than the electronics. That needs a technician.
Same-day service on most repairs. Flat-rate quote before any work begins.
St. Louis Garage Door Repair is a family-owned garage door service, covering the St. Louis metro on both sides of the river.