Why won’t my garage door close?
Nine times out of ten, the safety sensors. The two little eyes near the floor on each side of the opening must see each other before the opener will commit to closing. Anything that breaks or bends that beam, and the door starts down, changes its mind, and runs back up while the opener light flashes.
How do I check the safety sensors?
Kneel by each sensor and look for the small indicator lights.
- One sensor glows steady (the sender) and the other should too (the receiver). A dark or flickering receiver light means the beam isn’t landing.
- Look down the beam line. A rake handle, a trash bin wheel, a kid’s bike pedal: the beam is five inches off the floor, prime clutter altitude.
- Check for a bumped bracket. The sensors mount on soft steel brackets, and one nudge from a mower deck angles the eye off target. Loosen the wingnut, aim it at its partner until the light steadies, and retighten.
- Wipe both lenses. West-side dust plus a spider’s web is plenty to blind one.
Sunset matters here, and it’s a genuinely local quirk: a west-facing garage catches low sun straight down the beam line at certain times of year, and the receiver reads the glare as a blocked beam. If your door refuses only on clear evenings, that’s your culprit. A short cardboard shade tube over the receiver eye fixes it for good.
The sensors check out but it still won’t close
- Count the opener light’s flashes. Most units blink a code: on LiftMaster-style openers, ten flashes is the sensor circuit; other counts point at wiring or the board. The manual’s code table (searchable by the model number on the motor case) turns the blinking into a part name.
- Watch where it quits. A door that gets most of the way down and rolls back has its close-force or travel limit set wrong, common after any other door work. A door that reverses immediately is almost always sensors.
- Listen for a pop or scrape at one spot. That’s mechanical: a flattened roller or track dent, not opener logic, and the opener repair page versus a track repair call gets sorted on the phone in one minute.
How do I close the door tonight while it’s acting up?
Two safe options, in order of preference.
- Hold the wall button down. Holding (not tapping) overrides the sensor check on most openers and walks the door down under power. If it closes this way, you’ve confirmed the sensors are the issue and you’re secure until morning.
- Pull the red release cord with the door DOWN if you can get it there, then slide the manual latch if the door has one. Never pull the release with the door up unless you’re ready to control its full weight coming down.
An open garage overnight isn’t a risk worth taking. If neither trick closes it, the emergency page is the fast path, and doors that won’t secure go first in line.