Troubleshooting · Garage Door Repair
Garage Door Won't Close: Causes and Fixes
The short answer: Most of the time a garage door that won't close is caused by a blocked, dirty, or misaligned photo-eye safety sensor near the floor, which you can usually fix yourself in a few minutes.
A garage door that goes up fine but refuses to close, or starts down and then reverses, is one of the most common garage door problems, and it is rarely as serious as it feels. In the large majority of cases the culprit is the pair of small photo-eye safety sensors mounted a few inches above the floor on each side of the door. These sensors are federally required on residential openers made since 1993, and they will intentionally stop the door from closing whenever their beam is broken or misaligned.
This guide walks through the likely causes in roughly the order you should check them, from the quick free fixes to the ones that need a professional. It also flags which repairs are safe to do yourself and which involve enough stored energy to seriously injure you. When in doubt, the springs and cables are the two parts you should never touch without training.
Symptom, likely cause, fix, and typical 2026 US cost. DIY-safe items cost only your time.
| Symptom | Likely cause | Fix | DIY or pro | Typical 2026 cost |
|---|---|---|---|---|
| Door reverses right after starting down | Blocked, dirty, or misaligned photo-eye sensor | Clear path, wipe lenses, realign until LEDs are steady | DIY | $0 |
| Opener light blinks, door won't move down | Broken sensor beam or faulty sensor | Realign; if dead, replace the sensor unit | DIY / Pro | $85-$250 to replace |
| Remotes do nothing, wall button works | Lock/vacation mode on, or dead remote battery | Toggle off lock mode; replace remote battery | DIY | $0-$10 |
| Door stops partway and reverses, no obstruction | Close-limit or force setting off | Adjust down-limit per opener manual | DIY (careful) | $0, or ~$75-$150 service call |
| Door slams down or is very heavy to lift | Broken torsion/extension spring | Replace spring(s), always in pairs | Pro only | $150-$350 per spring; ~$300-$500+ for both |
| Door closes crooked or cable dangles | Frayed, loose, or off-drum cable | Replace both cables, re-tension | Pro only | $150-$350 |
| Nothing responds at all | Opener unplugged, tripped GFCI, or motor failure | Check power first; then diagnose opener | DIY / Pro | $0, or $100-$300+ opener repair |
Start here: the photo-eye safety sensors
If your door lifts normally but won't close, or closes an inch and reverses, check the sensors first. You have two small units near the floor, one on each door track, connected by an invisible infrared beam. The opener will not let the door close if that beam is broken. A telltale sign is the opener light blinking or the sensor LEDs not showing a steady glow.
Work through these checks in order, and cycle the door after each one to see if it closes:
- Clear the path: remove trash cans, cords, tools, a stray broom, or anything sitting in the doorway or leaning near a sensor.
- Wipe the lenses: sun glare, dust, cobwebs, or condensation on the small glass lens will block the beam. Clean each lens gently with a dry or barely damp soft cloth.
- Check alignment: a bumped bracket can knock a sensor out of line. Most sensors have one green/amber LED that stays solid when aligned and blinks or goes dark when not. Gently nudge one sensor until both LEDs are steady.
- Inspect the wires: look for chewed, pinched, or loose sensor wires, and make sure both sensors sit at the same height, ideally under 6 inches off the floor.
- Rule out sun interference: direct low-angle sunlight hitting a lens can mimic a blockage. Test at a different time of day or shade the lens with your hand.
Other common causes worth checking
If the sensors are clean, aligned, and both showing steady lights but the door still won't close, move on to these. Several are simple settings or user errors that take only a minute to rule out.
- Lock mode engaged: many wall consoles have a lock or vacation button. If it is on, the remotes are disabled and the door may not respond. Press and hold it to toggle it off.
- Close-limit / travel settings: if the door closes partway and reverses with no obstruction, the opener's down-limit may be set wrong, telling the opener the door has hit the floor early. Openers have limit adjustment screws or buttons; consult your model's manual before adjusting.
- A real obstruction or track debris: a small stone, hardened grease, or a bent track section can physically stop the door and trigger the auto-reverse. Look and feel along both tracks.
- Remote or keypad issues: dead remote battery, a keypad that lost its code, or an unplugged opener. Try the hardwired wall button; if that works, the problem is the remote, not the door.
- Manual lock or disengaged trolley: the red emergency-release cord may have been pulled, leaving the door in manual mode. Re-engage it per your manual, with the door fully closed.
The serious causes: broken springs and cables
If the door feels extremely heavy, closes crooked, slams down, or you see a visible gap in a coiled spring above the door or a frayed/dangling cable, stop using it. These parts carry the door's entire weight under high tension.
A single garage door can weigh 130 to 350+ pounds, and the torsion springs above the door store enough energy to break bones or worse if they let go. Cables are under the same load. Adjusting, winding, or replacing springs and cables is not a DIY job. This is the one category in this guide where you should always call a licensed garage door technician with the proper winding bars and clamps.
Signs you are in spring or cable territory: a loud bang from the garage (a snapped spring), the door won't lift at all or only rises a foot, one side hangs lower than the other, or the cable has come off its drum. Do not try to force the door or run the opener, which can worsen the damage or burn out the motor.
DIY vs. call-a-pro
Use this as a quick rule of thumb. Anything involving the springs, cables, or the door coming off its tracks belongs to a professional because of the injury risk; almost everything else is safe to try yourself with the opener unplugged when you are working near moving parts.
- Safe DIY: cleaning and aligning sensors, clearing obstructions, toggling lock mode, replacing remote batteries, reprogramming a keypad, minor track cleaning.
- Cautious DIY (read your manual first): adjusting close-limit and force settings, replacing a photo-eye sensor unit, re-engaging the emergency release.
- Call a pro: broken or worn torsion/extension springs, frayed or off-track cables, a door off its rollers or tracks, opener motor or logic-board failure, and any repair where you cannot identify the cause.
Frequently asked questions
- Why does my garage door open but not close?
- Almost always a photo-eye safety sensor issue. The opener is designed to lift freely but refuse to close whenever the sensors' beam is blocked or misaligned. Clean both lenses, remove anything in the doorway, and adjust the sensors until each shows a steady LED. If the lights are solid and it still won't close, check for lock mode, a limit-setting problem, or a track obstruction.
- How do I know if my garage door sensor is bad versus just dirty?
- Start by cleaning the lenses and realigning the sensors. If one sensor's LED still won't glow steadily after cleaning and alignment, and the wiring looks intact, the sensor itself is likely faulty. Replacement units are inexpensive and a manageable DIY job, or a technician can swap them during a service call.
- Is it safe to replace a garage door spring myself?
- No. Torsion and extension springs are under extreme tension and store enough energy to cause serious injury or death if they release suddenly. Spring replacement requires proper winding bars, clamps, and technique. This is the one repair that should always go to a licensed garage door professional, even for experienced DIYers.
- How much does it cost to fix a garage door that won't close in 2026?
- It depends entirely on the cause. Sensor cleaning or alignment is free if you do it yourself. A replacement sensor runs about $85-$250. Cable replacement is roughly $150-$350, and spring replacement is about $150-$350 per spring, often $300-$500 or more for a pair with labor. A basic diagnostic service call is typically $75-$150.
- What is the lock button on my garage door wall control?
- It is a security feature (sometimes labeled lock or vacation) that disables the remotes so no one can open the door from outside. If it is accidentally engaged, the door may stop responding to your remote or keypad. Press and hold the lock button for a few seconds to toggle it off.
- My garage door closes then immediately opens back up. What's wrong?
- This auto-reverse is a safety response. First check the photo-eye sensors, since a broken beam causes exactly this behavior. If the sensors are fine, the down-limit or force setting may be off, telling the opener the door hit the floor too soon, or there may be a physical obstruction or debris in the tracks stopping the door's travel.