Why Won't My Garage Door Close?

A garage door that will not close, or starts down and reverses, is most often blocked or misaligned safety sensors near the floor, and cleaning or realigning them fixes it for free. If the sensors are fine, the cause is usually an obstruction in the track, a travel or force setting that needs adjusting, or a broken spring or cable, and springs and cables are a job for a garage door technician.

The free checks

1. Look at the safety sensors. They are the two small units on either side of the door, a few inches above the floor. Both usually have a light. If one is off or blinking, they cannot see each other.
2. Clear and clean them. Remove anything in the beam path, like a broom, a bike tire, or a spiderweb, and wipe the lenses with a soft cloth.
3. Realign them. Loosen the wing nut, point each one straight at the other, and tighten until both lights are steady. They often get bumped by bins and bikes.
4. Check the wall control for a lock or vacation button, and replace the remote battery.
5. Look along both tracks for anything blocking the rollers, and for dents or bends.
6. Hold the wall button down. On many openers, holding the button closes the door even when the sensors are not working. Use this only to secure the house while you sort out the problem, and watch the door the whole way down.

If it reverses at the floor

A door that closes all the way, touches the floor, and goes right back up usually needs its close limit or force setting adjusted. Many openers have buttons or dials for this. The manual, often available online by the model number on the motor unit, shows how. Make small adjustments and test the safety reversal afterward: place a piece of 2x4 lumber flat on the floor under the door. The door should reverse when it touches it.

Signs of a broken spring

• A loud bang from the garage, often when no one was using the door.
• A visible gap in the coiled spring on the bar above the door, or a stretched-out spring along the tracks on older doors.
• The opener strains and the door barely lifts, or lifts a few inches and stops.
• Cables hanging loose by the bottom corners.

If you see any of these, stop using the opener. Running an opener against a broken spring can damage the opener and the door. If both springs are the same age, many technicians recommend replacing them as a pair, since the second one is often close behind.

Keeping it running

• Lubricate rollers, hinges, and springs once or twice a year with a garage door lubricant, not grease, which collects dirt.
• Test the auto-reverse monthly with an object under the door.
• Replace the bottom seal if you see daylight under the closed door or water and leaves blowing in.
• Keep bins, bikes, and tools away from the sensors.