Garage door will not close, or closes then reopens
A door that will not close is almost always the photo eyes, not the opener. Federal rules require a blocked beam to prevent the opener closing an open door at all, so a dirty lens stops the door completely. Clean both lenses, clear the opening, and check the indicator lights.
Causes, most common first
| Cause | How to test it | Verdict |
|---|---|---|
| Photo eye lens dirty or beam blocked | Look for a flickering or dark LED; wipe both lenses and clear the opening | Safe to DIY |
| Photo eye bracket knocked out of alignment | Loosen the wing nut and tilt until the LED goes steady | Safe to DIY |
| Low sun shining into the receiving eye | Shade the receiver by hand and retry | Safe to DIY |
| Travel limit set too far, so the door hits the floor and reverses | Watch whether it reverses after touching down rather than before | Safe to DIY |
| Obstruction or debris in the track | Run your eye along both tracks at floor level | DIY with caution |
| Damaged low-voltage sensor wire | Follow the wire for pinches or staple damage | DIY with caution |
How does a garage door actually hold its own weight?
A garage door is not lifted by the opener — it is lifted by the spring, and the opener only guides it. A residential door weighs 85 to 400 pounds, and the counterbalance holds that weight so the motor only has to overcome friction. That is why springs and cables are professional work while sensors and remotes are not: one group holds the stored energy and the other does not.
Garage door safety covers the balance test and what an unbalanced door does to an opener.
What order should I check things in?
Cheapest and safest first, because that order also happens to be the most likely. Start with the remote battery, then the wall button, then whether the opener has power at the outlet — a tripped GFCI accounts for more "dead openers" than any component failure.
Next check the photo eyes, because a blocked beam does not merely interrupt one cycle. Federal rules require secondary entrapment protection to prevent the opener closing an open door at all while the beam is broken, so a filmed-over lens presents as a completely dead door in the closing direction.
Only then test the door itself. Pull the red release with the door closed and lift by hand. If it moves freely, you have an opener or control problem. If it is very heavy, you have a counterbalance problem, and that is where the DIY path ends.
The federally required text in your own manual draws the same line: it directs cable and spring repairs to a qualified service person, and it says never to go under a stopped, partially open door.
What does federal law actually require here?
Every residential opener manufactured since January 1, 1993 for US sale must meet 16 CFR 1211: a closing door must begin reversing within 2 seconds of hitting an obstruction, a second independent protection system must exist, and the manual release must be red. §1211.16(b) also fixes the exact words your manual carries — among them “Have a qualified service person make repairs to cables, spring assemblies and other hardware.” — which is why this page's verdict is not our opinion.
What UL 325 and 16 CFR 1211 require covers the full standard.
What is the one-minute test everyone should be doing?
The reversal test, monthly, with a 2x4 laid flat in the door's path: it must reverse on contact. If it does not, stop using the opener until it is adjusted, repaired or replaced. It matters because this system fails silently — a door whose reversal has stopped working looks and sounds exactly like one that still does. CPSC recommends inspecting the door and opener every 30 days.
Children, pets and the garage door covers why the standard exists.
At what point should I stop and call someone?
- The door is very heavy by hand with the opener disconnected. The counterbalance has failed.
- You can see a gap in the spring coil, or a cable that is frayed, slack, or off its drum.
- The door sits crooked, higher on one side, or has come off its track. It is still under full tension.
- The door does not reverse on the board test. The entrapment protection is not working.
None of those is calling too early, and the rule worth teaching at home comes from that same federal text: “NEVER GO UNDER A STOPPED PARTIALLY OPEN DOOR.”
Questions that come up next
Does a door that reverses mean something is broken?
No — the opposite. A door that stops and goes back up when it touches something is the entrapment protection doing exactly what 16 CFR 1211 requires. The fault worth investigating is a door that fails to reverse.
Can I disable the photo eyes to get the door closed?
No. That removes the external entrapment protection required since 1993, and it is the protection that exists because of the CPSC child fatality record. If a sensor is genuinely faulty, replace it — it is among the cheapest parts on the door.
Is it safe to use the emergency release with the door open?
The federally required manual text says to use it only when the door is closed wherever possible, because weak or broken springs may allow the door to fall rapidly. A great deal of DIY content advises the opposite.
Should I replace one spring or both?
If the door has two, quote both. The second is the same age and has taken the same number of cycles, so it is next. This is one of the few upsells in the trade that is genuinely honest.
Sources
- 16 CFR Part 1211 — Safety Standard for Automatic Residential Garage Door Operators — US Consumer Product Safety CommissionTier 1 accessed
- Publication 523 — Non-Reversing Automatic Garage Door Openers Are a Hazard — US Consumer Product Safety CommissionTier 1 accessed