A garage door that closes partway and then reverses back up is doing exactly what it's supposed to do — the opener's safety system detected a problem and stopped the door before it could hurt anything. The question is: why. Here are the five causes in order of likelihood.
1. Photo-Eye Sensors Are Blocked or Misaligned
The #1 cause. If the safety sensors near the floor can't see each other or their beam is broken, the door reverses. Check both sensor LEDs — both should be steady. Common blockers: dust on the lenses, spider webs, a loose broom leaning against one, sun glare late afternoon. See our LiftMaster sensor guide.
2. Close-Force Setting Too Sensitive
Every opener has a screw that adjusts how much resistance triggers a safety reversal. If your door was recently serviced and rollers/springs were changed, the door's "resistance profile" changed — the opener now feels the new (correctly balanced) door as unusual and reverses.
Fix: On the back or side of the opener, look for a screw labeled DOWN FORCE. Turn it clockwise a quarter-turn at a time and re-test after each. Don't go past what's actually needed — too much force defeats the safety system.
3. Travel Limit Set Wrong
The travel-limit setting tells the opener when the door is fully closed. If it's set to travel further than the door actually can, the door hits the concrete before the opener expects — the opener reads that as an obstruction and reverses.
Fix: On the opener, look for DOWN TRAVEL or DOWN LIMIT. Adjust in small increments until the door touches the floor without slamming.
4. Rollers or Track Are Binding
Worn or dry rollers create friction on the way down. The opener senses that friction as an obstruction. Spray the roller stems and hinges with white lithium garage door lube (not WD-40, which strips existing grease). If rollers are visibly rusty or wobbling in their stems, replace the set — $150–$350 installed.
5. Spring Failing (Just Started)
If a spring is losing tension (about to snap), the door gets heavier — making the opener strain and trigger a reversal on close. Warning signs: door feels heavier than usual to lift by hand, one spring visibly stretched compared to the other, opener sounds like it's straining. If you see these, stop using the door and see our spring emergency guide.
What to Check in Order
- Sensor LEDs steady? If not, realign.
- Anything visibly under the door path? Clear it.
- Rollers dry / squeaky? Lube.
- Door heavy to lift by hand? Call for spring check.
- None of the above? Force / travel limit adjustment.
When to Call a Pro
Force and travel limits should be dialed in carefully — getting them wrong creates a safety hazard. If steps 1–4 don't fix it, or you notice unusual sounds during operation, we can diagnose and rebalance in a single visit. Trip charge waived on online bookings.