A garage door that reverses before closing when operated by remote is usually triggered by the safety reversal system detecting an obstruction or fault. This system, required by law since 1993, uses infrared sensors near the floor and the motor’s force settings to prevent entrapment. If the door starts to close but immediately reverses, the opener believes something is in the way or that excessive force is needed, even if nothing is visible. The first step is to check for obvious obstructions like debris, tools, or ice buildup in the door’s path.
Safety Sensor Alignment and Obstruction
The most common cause of premature reversal is misaligned or blocked safety sensors. These are the small photo-eye units mounted on each side of the door, about 4-6 inches above the floor. They emit an invisible infrared beam; if the beam is broken, the door will not close and will reverse if already moving. Dirt, spider webs, or condensation on the lenses can interrupt the beam. Check that both sensor lights are solidly lit — not flickering or off. Clean the lenses with a soft cloth and adjust the brackets until both lights remain steady. Even slight misalignment from bumping the sensors can cause failure.
