Garage Door Won't Close? Here's Everything That Causes It
If your garage door goes up without complaint but refuses to come back down — maybe it starts, stops, and reverses, maybe it just clicks, maybe the opener light blinks at you — you're most likely looking at the safety sensors. That's the cheapest and most common cause, and it's one you can very often fix yourself in the time it takes to find a flashlight. But it isn't the only cause. There are about eleven things that produce this exact complaint, and a few of them aren't the opener at all — they're the door, and the opener is just the part that gave up first. This page walks through all of them, in the order we work through them on a real service call.
This is general guidance based on what we see on service calls — it isn’t a substitute for someone looking at your actual door. Every door is a little different, and if anything here feels beyond what you want to take on, stop and give us a call.
First — if any of this is true, stop using the door
Most won't-close problems are harmless. These few aren't, and running the opener will make them worse or hurt someone.
- You heard a loud bang — like a gunshot or a heavy pipe dropping — and the trouble started right after.
- You can see a visible gap or a break in the spring on the shaft above the door.
- One of the lift cables is hanging loose, frayed, or has come off its drum.
- The door is visibly crooked in the opening, or one side sits noticeably lower than the other.
- The door is hanging at an angle, or a roller has come out of the track.
- You smell burning, or the opener motor is hot to the touch.
In every one of these cases the door's weight is no longer being carried the way it's supposed to be — which means the opener is either about to be destroyed trying, or the door is one cycle away from coming down hard. Leave it closed if it's closed, leave it open if it's open, keep people and cars out from under it, and call us. A door in that condition needs garage door opener repair before it gets used again, not another button press.
Call (602) 935-9766What to check in the next 10 minutes
Assuming none of the above applies, run these five before you call anybody. Any one of them might be the whole problem, and together they cover most of what we get called out for.
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1Look at the two little sensors near the floor
One on each side of the door opening, about six inches up. Both should have a light on, and both should be steady. If either is off, dim, blinking, or flickering, that's your answer — keep reading.
You’ll know it worked when: Both lights are on and steady, not blinking.
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2Clear whatever's in the beam
A trash bin, a bike tire, a coiled hose, a stack of boxes, a broom leaning at the wrong angle, even a pool noodle. The beam is invisible and it only takes a sliver of something to break it.
You’ll know it worked when: You can see clean floor between the two sensors with nothing crossing that line.
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3Wipe both lenses
Soft dry cloth. Out here they collect a film of fine dust you genuinely cannot see until you wipe it and look at the cloth. This alone fixes a lot of calls in monsoon season.
You’ll know it worked when: The lens is clear and the light stayed on while you cleaned it.
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4Nudge them into line
Gently — they sit in a bracket that bends easily. Aim each one straight across at its partner. Somebody bumping a sensor with a car door, a bike, or a lawn mower is the single most common reason they drift.
You’ll know it worked when: Both lights go solid and stay solid when you let go.
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5Check the wall panel for a lock light
Most modern wall controls have a Lock button. If it's been pressed — often by a kid, or by someone leaning on the panel — the opener will ignore every remote, and on many models it won't close at all. Hold the Lock button for a couple of seconds to toggle it off.
You’ll know it worked when: The lock indicator on the wall panel is off, and your remote works again.
One question tells us most of what we need to know
Before you touch anything else, try this. It's the first thing we ask on the phone, because the answer splits the problem cleanly in half and saves you troubleshooting the wrong side of it.
Fair warning on the hold-the-button trick: it works precisely because it switches off the system that stops the door on a child or a pet. Use it once, to diagnose, with the doorway in clear view — never as a way to live with a broken sensor.
Which version of this is happening to you?
“Won't close” covers several genuinely different faults, and they point at different parts of the system. Find the one that matches and you've narrowed it a long way.
The opener began the close cycle and then something interrupted it — the sensor beam broke, or it hit resistance. Classic sensor or track obstruction.
Jump to that fix ↓Different fault entirely. The door completed its travel and the opener read the floor contact as an obstruction — that's a close-limit or down-force setting, not the sensors.
Jump to that fix ↓The opener never even attempts the close. It's refusing at the safety check, before the motor engages. Sensors, or lock mode.
Jump to that fix ↓The trolley has come disconnected from the door — usually because the emergency release was pulled and never re-engaged. The opener is running happily with nothing attached.
Jump to that fix ↓Not really a close problem at all — that's a remote, lock mode, or radio interference issue. The door itself is fine.
Jump to that fix ↓Almost always sun angle hitting the receiving sensor. Very common here on west-facing garages in the afternoon.
Jump to that fix ↓Why your opener refuses to close (and why that's a good thing)
It helps to know what's actually going on, because once you do, most of the fixes below stop feeling like guesswork.
Since 1993, federal law has required every residential garage door opener sold in the United States to have a secondary entrapment protection system — in practice, the pair of photo eyes near your floor. The opener is built to the UL 325 safety standard, and that standard says it must refuse to close unless it can positively confirm two things: that the beam between the sensors is unbroken, and that the sensors are wired and reporting properly. Not “probably fine” — positively confirmed. Silence is treated as failure.
That's why a dead sensor produces the same behavior as a blocked one. The opener isn't being fussy; it's designed to fail safe. A door that closes when it can't verify the path is clear is a door that can close on a child, and the whole point of the standard is to make that impossible.
There's a second safety system running alongside it. Your opener continuously monitors how much force closing the door takes. If it meets more resistance than it expects, it assumes it hit something and reverses. That's what catches the obstruction the photo eyes can't see — something on the floor beneath the door, or a person's foot. This is also why a mechanical problem with the door shows up as a close failure: to the opener, a binding track and a child's shoulder feel exactly the same.
So when your door won't close, the opener is almost always telling you something real. The job is working out which of its two safety systems is objecting, and why.
Match what you're seeing
The exact way the door misbehaves narrows this down fast. Find your row.
| What you’re seeing | Most likely cause | How urgent | Who should fix it |
|---|---|---|---|
| Opener light blinks 10 times, door won't move down | Safety sensors blocked, misaligned, or unpowered | Fix today — the door is unusable | You can do this |
| Door starts down, then reverses back up on its own | Sensor beam breaking mid-travel, or an obstruction in the track | Fix today | You can do this |
| Door closes only while you hold the wall button | Sensors — the hold override is bypassing them | Fix today, don't rely on the override | You can do this |
| Nothing happens from the remote, but the wall button works | Lock mode engaged, dead remote battery, or lost programming | This week | You can do this |
| Door reverses the instant it touches the floor | Close travel limit set too far, or down-force too low | This week | Either — call us if unsure |
| Motor runs but the door doesn't move at all | Trolley disconnected from the door, or a stripped drive gear | This week | Either — call us if unsure |
| Door stops at the same spot every time | Something binding in the track at that height | Stop using it if it's forcing | Call a pro |
| Door feels heavy or slams when you lift it by hand | Broken or fatigued spring — the door, not the opener | Stop using it — call us today | Call a pro |
| Loud bang, and now it won't close (or open) | Almost certainly a broken torsion spring | Stop using it — call us today | Call a pro |
| Works fine in the morning, refuses in the afternoon | Low sun washing out the receiving photo eye | Fix this week | You can do this |
| Closes and reopens on a schedule you didn't set | Timer-to-close feature, or an app automation | Whenever | You can do this |
What’s actually causing it
These are ordered the way we work through them on a real service call — cheapest and most common first, so you don’t start by replacing a part that was never the problem.
The safety sensors are out of alignment
Basic checkThis is far and away the most common cause. The sensors sit low in a busy garage in brackets that bend if you look at them wrong, and it takes only a few degrees of drift to break the beam. A car door, a bike handlebar, a lawn mower, a kid's scooter, or just the vibration of the door cycling a few thousand times will do it.
How you can tell: One sensor's light is off, dim, or blinking while the other is steady. On LiftMaster and Chamberlain units the opener's light also blinks 10 times when you press the button.
- Find both sensors — one each side of the opening, roughly six inches off the floor.
- Note which light is misbehaving. Generally the sending eye is amber or yellow and the receiving eye is green, though it varies by brand.
- Loosen the wing nut or bracket screw just enough that the sensor can pivot — you don't need to remove anything.
- Aim it straight across at its partner and watch the light. When it goes solid and stays solid, you've found the line.
- Hold it there and snug the bracket back down without letting it drift.
- Test the door with the remote, not the wall button, so you're not accidentally using the override.
You’ll know it’s right when: Both sensor lights burn steady, and the door closes all the way without reversing.
A sensor lens is dirty, fogged, or spider-webbed
Basic checkThe lens is a small plastic window, and anything on it scatters the beam. Fine dust is the usual culprit here, but we also find spider webs (they love the warm sensor housing), grass clippings, overspray from someone painting, and condensation inside the housing on units with a cracked seal.
How you can tell: Both lights are on and aimed correctly, but the door still won't close — or it works intermittently with no pattern.
- Wipe both lenses with a soft dry cloth. Don't use solvent — it can haze or craze the plastic.
- Look inside the housing for a web or an insect nest and clear it out.
- If you see moisture inside the lens, the housing seal has failed and the sensor needs replacing.
- Check that the lens isn't scratched or clouded from age — a 20-year-old sensor can simply be worn out.
You’ll know it’s right when: The lens is visibly clear and the door closes normally.
A sensor wire is nicked, pinched, or corroded
Hands-on — moderate riskThe sensors run on thin two-conductor wire stapled along the wall and up to the opener. It's easy to catch with a shovel, pinch behind a shelf bracket, staple through when someone's hanging something, or nick with a weed trimmer. Rodents chew it too. The failure is often intermittent — the door works some days and not others — because a partly broken conductor makes and breaks contact as the wire moves or as the garage heats up and everything expands.
How you can tell: A sensor light that's completely dead no matter how you aim it, or a door that works fine some days and refuses on others with no pattern you can pin down.
- Follow the wire from each sensor along the wall as far as you can see, looking for cuts, staple punctures, kinks, or green corrosion at the connectors.
- Check where the wires land at the opener's terminal block — a wire that's backed out of a terminal is very common.
- Gently wiggle the wire near each sensor while watching the light. If it flickers, you've found your break.
- Look especially where the wire passes a corner, a stud, or anything that's been mounted to the wall since the opener went in.
You’ll know it’s right when: The sensor light stays rock steady while you flex the wire along its whole run.
Sunlight is blinding the receiving sensor
Basic checkThis one catches people out because nothing is broken. The receiving photo eye is looking for a specific infrared signal, and when low direct sun floods it, the signal gets lost in the noise. The opener reads that as a blocked beam and refuses. It's genuinely common here, and it's the reason a door can behave perfectly for months and then start acting up in a particular season as the sun angle changes.
How you can tell: The door works fine in the morning, gets stubborn in the late afternoon, and behaves again after sunset. Usually a west-facing garage, and usually worse in winter when the sun sits lower.
- Note the time of day it fails and check whether direct sun is falling on either sensor at that hour.
- Test the theory: shade the receiving sensor with your hand or a piece of cardboard and try the door again.
- If that fixes it, fit a permanent shade — a small hood, a piece of PVC pipe split lengthwise, or a purpose-made sensor shield.
- Alternatively, swap the two sensors side for side so the receiving eye faces away from the sun.
You’ll know it’s right when: The door closes normally at the time of day it used to fail.
Lock mode is on, or the wall button is stuck
Basic checkMost modern wall controls have a Lock or Vacation button that deliberately disables all remotes — it's a security feature for when you're away. It's also very easy to press by accident, and children find it fascinating. Separately, a wall button whose contacts have stuck closed will hold the opener's circuit and prevent normal operation entirely.
How you can tell: For lock mode: the wall button works but no remote does, and there's usually a small lit indicator on the panel. For a stuck button: nothing works at all, and the opener may buzz or click steadily.
- Look at the wall panel for a Lock or Vacation indicator light.
- Press and hold the Lock button for about two seconds to toggle it off. The indicator should go out.
- If nothing works from anywhere, press the wall button and feel whether it springs back cleanly. A mushy or stuck button needs replacing.
- To rule the wall button out entirely, disconnect its two wires at the opener terminal briefly and try a remote.
You’ll know it’s right when: The lock light is off and your remotes work again.
The close travel limit is set too far
Hands-on — moderate riskYour opener stores a position it considers “fully closed.” If that setting has drifted — or was never right — the opener keeps driving after the door has already met the floor. It feels that resistance, decides it hit an obstruction, and reverses. This is the specific cause behind the very distinctive symptom of a door that touches down and immediately rides back up.
How you can tell: The door goes all the way down, contacts the floor, and immediately reverses. Sensor lights are steady the whole time. This is the signature.
- Find the limit adjustments — on newer units they're buttons behind a panel or under a light cover, on older ones they're plastic screws marked with arrows or “up” and “down.”
- Reduce the down-travel slightly so the door stops right as it seats on the floor rather than pushing into it.
- Make small changes — a quarter turn, or a single button press — and test between each one.
- When it's closing properly, run the safety reversal test: lay a 2x4 flat on the floor directly under the center of the door, running across the opening on the floor in the door's path and close the door. It must reverse when it touches the board.
- If it doesn't reverse on the board, reduce the down-force setting and test again until it does.
You’ll know it’s right when: The door seats fully on the floor without straining, and still reverses promptly when it meets the 2x4.
The down-force setting is too low
Hands-on — moderate riskClose force is how hard the opener will push before it assumes it hit something. Set too low, ordinary friction — a dry roller, a slightly stiff hinge, a bit of weather seal dragging — reads as an obstruction. This tends to creep up on you: the door gets a little stiffer over a year or two, and eventually crosses the threshold where the opener starts refusing.
How you can tell: The door reverses at no consistent point, or it started reversing gradually over weeks rather than all at once. Often accompanied by the door sounding a bit rougher than it used to.
- Close the door and unplug the opener before you start — a timer-to-close, an app, or someone pressing a remote in the driveway can start the door while your hands are in the hardware.
- Before touching the force setting, lubricate the rollers, hinges, and the torsion spring with a garage-door-specific lubricant. Very often this alone fixes it.
- Pull the emergency release with the door closed and lift it by hand. It should feel like around ten pounds and stay put where you stop it.
- If the door moves easily by hand but the opener still reverses, increase the down-force slightly — a small increment only.
- Re-run the 2x4 safety reversal test after any force change, without exception.
You’ll know it’s right when: The door closes smoothly, and it still reverses on the 2x4.
The trolley is disconnected from the door
Basic checkThe red cord hanging from the rail disconnects the door from the opener so you can move it by hand during a power cut. Once pulled, the opener will run its whole cycle happily with nothing attached — motor humming, chain moving, door sitting exactly where it was. People pull it during an outage and then forget, or a tall vehicle catches it on the way in.
How you can tell: The motor runs for the full normal cycle and the door doesn't move at all. You can lift the door freely by hand.
- Close the door fully by hand.
- Pull the red cord toward the door (rather than straight down) to reset the release lever — on most units you'll hear it click into the ready position.
- Run the opener. The trolley will travel along the rail and re-latch onto the carriage automatically with an audible click.
- Cycle the door once to confirm it's properly engaged.
You’ll know it’s right when: The door moves with the opener again, and the trolley is visibly latched to the carriage.
The remote or keypad has lost its programming
Basic checkStrictly this is a “won't close from the remote” problem rather than a won't-close problem, but people describe it the same way and it belongs here. Rolling-code openers occasionally lose a remote's registration after a power surge, a board reset, or a battery change that took too long. Keypads lose their PIN the same way.
How you can tell: The wall button closes the door perfectly. The remote or keypad does nothing at all, or only works from a few feet away.
- Change the remote battery first — a weak battery gives short range before it gives none.
- Confirm lock mode is off at the wall panel.
- Find the Learn button on the opener head (usually under the light cover, and colored — the color tells you the security generation).
- Press and release Learn — do not hold it, holding it erases everything — then press the remote button within 30 seconds. The opener light will flash or click to confirm.
- If range is poor rather than absent, check that the opener's antenna wire is hanging down freely and hasn't been cut or tucked up.
You’ll know it’s right when: The remote works reliably from the end of the driveway.
Something is binding in the track
Hands-on — moderate riskYour opener cannot tell the difference between a child in the doorway and a roller catching on a bent section of track. Both are resistance, and both make it stop and reverse. A dented track, a loose bracket, a roller that's lost its bearings, a hinge that's pulled loose, or a section that's shifted will all read as an obstruction — usually at the same point in the travel every single time.
How you can tell: It stops and reverses at the same height every time, or you can hear a scrape, thunk, or grind right before it gives up.
- Watch the door close and note exactly where it stops. That's where the problem is.
- With the door open, inspect both tracks at that height for dents, gaps between track sections, or brackets pulling away from the wall.
- Check the rollers at that point — a roller that won't spin freely between your fingers is worn out and needs replacing.
- Check the hinges at that section for cracks or elongated bolt holes.
- Tighten any obviously loose track brackets and lag bolts, but don't overtighten into the drywall.
You’ll know it’s right when: The door runs its full travel with no scraping and no hesitation at that spot.
The problem is the door, not the opener
High risk — call a technicianHere's the one people don't expect, and the reason we check it on every single won't-close call. A garage door is a counterbalanced system: the springs above the door carry almost all of its weight, and the opener only supplies the nudge that gets it moving. When a spring breaks or fatigues, the opener suddenly has to handle a door that weighs 150 to 250 pounds on its own. Modern openers are smart enough to refuse rather than destroy themselves trying — so a spring problem shows up wearing a sensor problem's clothing.
How you can tell: Pull the emergency release with the door closed and lift by hand. A healthy, balanced door should feel like roughly ten pounds and should stay put wherever you stop it — halfway, three-quarters, anywhere. If it's brutally heavy, if it slams down the moment you let go, or if it won't stay put, your springs are the problem and no amount of opener adjustment will fix it.
What your opener is telling you, by brand
LiftMaster & Chamberlain
These two are the same company, and they share a diagnostic language. Count the flashes of the opener's main light after you press the button — on newer units with an LED display panel, watch the UP and DOWN arrow LEDs instead.
| Light blinks | What it means | What to do |
|---|---|---|
| 1 blink | Safety sensor wire is disconnected or cut | Check both sensor wires at the opener terminal and along their run |
| 2 blinks | Safety sensor wire is shorted, or the sensor has failed | Look for a pinched or stapled-through wire; test by disconnecting one sensor at a time |
| 3 blinks | Door control (wall button) wire is shorted | Disconnect the wall button wires at the opener — if the fault clears, it's the button or its wiring |
| 4 blinks | Safety sensors are slightly misaligned, or the beam is briefly interrupted | Re-aim both sensors until the indicator LEDs are steady |
| 5 blinks | Motor overheated (thermal protection) or a motor circuit fault | Let it cool 15–30 minutes; if it repeats, the motor or board needs looking at |
| 6 blinks | Motor circuit failure | This is a service call — the logic board or motor is faulty |
| 10 blinks | Sensors blocked or badly misaligned — the most common code by far | Clear the path, clean both lenses, re-aim until steady |
Genie
Genie calls their photo eyes the Safe-T-Beam system, and it reports through two LEDs on the sensor housings rather than through the opener's main light.
| LED state | What it means | What to do |
|---|---|---|
| Both LEDs steady | System healthy — beam intact | Look elsewhere; this isn't your sensors |
| Receiving LED off | No power to that sensor, or wire fault | Check the wire run and terminal connections |
| Receiving LED blinking | Beam blocked or sensors misaligned | Clear the path and re-aim until steady |
| Both LEDs steady red | Travel limits were never set, or were lost | Re-run the limit-setting routine in your manual — this is not a sensor fault |
| Sending LED off | Sender has no power | Check its wiring back to the opener head |
Craftsman & older units
Craftsman openers were largely built by Chamberlain, so many share the blink codes above. Genuinely old units, though, often have no diagnostic blink at all — you have to read the sensor LEDs directly and work by elimination.
| What you see | What it means | What to do |
|---|---|---|
| No diagnostic light at all | Pre-diagnostic-era opener | Read the sensor LEDs directly; use the hold-the-button test to split sensor from non-sensor faults |
| Sensor LED dim rather than off | Weak connection or failing sensor | Check terminals first, then plan on replacing the pair |
| Opener predates 1993 | It may have no photo eyes at all | Strongly consider replacing it — it lacks the entrapment protection every modern opener is required to have |
What you’ll need if you’re doing this yourself
- A flashlight — sensor LEDs are dim and the brackets sit in shadow
- A soft dry cloth — for the lenses — no solvents, they haze the plastic
- A 7/16-inch or 1/2-inch wrench or nut driver — most sensor brackets and track bolts use one of these
- A stepladder — for reaching the opener head, limit adjustments, and the antenna
- A scrap 2x4 — for the safety reversal test — do not skip this after any adjustment
- Garage door lubricant — silicone or lithium spray made for doors; not the classic blue-can WD-40, which thins out fast, attracts dust, and can wash away the grease already there
- A fresh remote battery — usually a CR2032 or A23 — worth having on hand before you start reprogramming anything
Things not to do — and why
They've been required on every residential opener made in the US since 1993 (as secondary entrapment protection under 16 CFR Part 1211), and openers built to UL 325 won't run normally without them anyway. More to the point, they're the system that stops the door on a child or a pet. If a sensor has genuinely failed, replacing the pair is a small job.
Holding the button bypasses the safety reversal. A taped button is a door that will close on anything in its path, unattended, with nothing to stop it.
Force settings are a safety system, not a workaround. If the door needs significantly more force than it used to, something mechanical has changed — and turning up the force just means the door now has enough power to injure someone before it reverses.
The tracks carry the door's weight and keep it aligned. Metal that's been bent and straightened is weakened, and it fails later — usually with the door part-way up.
They hold enough stored energy to break bones, and winding bars are not the same as screwdrivers no matter what a video suggests. This is the single most common way homeowners get seriously hurt on a garage door.
Beyond the safety issue, you'll strip the opener's drive gear in short order. That turns a spring repair into a spring repair plus an opener repair, and sometimes plus a new opener.
A quick press starts programming. Holding it for several seconds erases every remote, keypad, and car button you've ever paired — which turns a five-minute job into an afternoon.
The classic blue can is a water-displacing penetrant, not a long-term lubricant. It thins out, attracts dust, and can wash away the grease already there. (WD-40's own white lithium grease is a different product and fine to use.). Use a silicone or lithium product made for garage doors.
Why this happens more in the Phoenix area
We fix this exact complaint constantly, and a good share of the calls come down to things that are genuinely worse here than most places.
The big one is the sun. Our photo eyes sit low and face straight across the opening, and for a stretch in the late afternoon — especially on a west-facing garage in winter, when the sun sits low in the sky — direct light can flood the receiving eye and wash out the beam it's looking for. The opener reads that as blocked and refuses. If your door works fine all morning, gets stubborn around four or five, and behaves again after sunset, you've almost certainly found your problem, and a small shade over the receiving sensor usually ends it for good.
- Afternoon-only trouble — low sun blinding the receiving sensor. Shade the eye, or swap the two sensors side for side.
- After a dust storm — fine silt films the lenses in a way ordinary dirt doesn't. It doesn't look dirty until you wipe it and check the cloth. Worth adding the lenses to your post-monsoon walkaround.
- Heat and the brackets — a closed garage here runs well past 130°F in summer, and everything in it expands. Sensor brackets that were dead-on in March can sit a few degrees off in July, and a few degrees is all it takes.
- Weather seal sticking — the rubber seal along the bottom of the door softens in extreme heat and can grab at the concrete, adding just enough drag to trip a marginal force setting.
- Springs age faster here — the daily heat cycling in an uninsulated Arizona garage is hard on steel, and springs in this valley tend to go before the ten years people plan around — that's our field observation, and DASMA's own recommendation is that doors in extreme-heat climates be kept closed where possible, and what that looks like on the ground here is springs falling short of the ten years a mild climate would give them. A spring that would have gone ten years in a mild climate often doesn't, which is why we always check door balance on these calls.
Keeping it from happening again
Most of what causes this is preventable with about fifteen minutes twice a year.
- Wipe the sensor lenses twice a year and always after a dust storm. Takes ten seconds and prevents a good share of these calls.
- Keep the sensor area clear — nothing stored within a foot of either sensor, so a shifting bin can't drift into the beam.
- Lubricate rollers, hinges, and the spring annually with a silicone or lithium garage-door lubricant. Reduces friction so your force settings stay comfortably in range.
- Run the 2x4 safety reversal test twice a year — it takes a minute and it's the single best check that your safety systems still work.
- Do the balance test twice a year — release the door, lift it by hand, and see whether it stays where you stop it. This catches a fatiguing spring months before it strands you.
- Watch for creeping changes — a door that's gradually gotten noisier or slower is telling you something. Problems announce themselves before they strand you.
- Consider a yearly tune-up if you'd rather not do the above yourself. We run all of these checks plus a full inspection, and it's the same price in every city we serve.
Where this sits in the bigger picture
When “won't close” turns out not to be the sensors, it's usually one link in a chain that started somewhere else. Knowing the order helps you catch the real problem rather than the symptom.
This is why we check door balance on a won't-close call even when the sensors look like the obvious culprit. Fixing a sensor on a door with a tired spring just means we're back in six weeks for something worse — and by then it's usually more expensive.
When it's worth having us out
Call us if the sensors are clean, aimed, and lit and it still won't close; if it stops at the same spot every time; if the door feels heavy or won't stay put when you lift it by hand; if you heard a bang before this started; or if you're finding yourself turning the force up to make it work. That last one especially — that setting is a safety system, not a workaround.
- Test both photo eyes and their wiring end to end, including the terminal connections at the opener head
- Read any diagnostic codes the opener is reporting and interpret them against your specific model
- Check the close-force and travel limits against the manufacturer's spec for your unit
- Run the safety reversal test the way UL 325 requires, and show you the result rather than just telling you
- Release the door and check its balance by hand — the step that catches a failing spring before it strands you
- Inspect tracks, rollers, hinges, cables, and brackets through the full travel
- Lubricate everything that should be lubricated while we're there
- Walk you through what we found and what we'd do about it before we touch anything
Same-day service is our standard across Mesa, Gilbert, Chandler, Queen Creek, Scottsdale, Tempe, Phoenix and the rest of the Valley.
When you want it handled rather than diagnosed, this is the page for it: garage door opener repair. Depending on what you find, garage door repair may be the closer fit.
What this usually costs to put right
We don't publish prices, because an honest number depends on what's actually wrong — and a won't-close call can be anything from a five-minute sensor alignment to a spring replacement. Here's what moves the number, so you know what we're weighing when we quote you.
- Whether it's alignment or a failed part Re-aiming a sensor is a very different job from replacing one, and both are different again from running new wire.
- Whether the wiring needs replacing A nicked wire we can splice is quick. A run chewed through inside a finished wall takes considerably longer.
- Whether the logic board survived Miswiring or a power surge can take out the board, which is the single most expensive component in most openers.
- Whether the real problem is the springs If the opener is refusing because the door is too heavy, you're looking at spring work — and spring size, cycle rating, and whether it's a one- or two-spring door all matter.
- Whether the track or rollers need work A worn roller is minor. A bent track section is a replacement, and if the door has been running on it a while there's often more than one. Track sections are quoted as garage door repair rather than folded into the opener line.
- Whether the opener is worth repairing at all On a unit past fifteen years with a failed board, we'll tell you honestly if replacement is the better spend rather than sinking money into it.
You'll get a written quote before any work starts, and no pressure at all if you'd rather sit on it. If you're due anyway, our full tune-up is $39.99 and it's the same price in every city we serve.
Still stuck? We’ll come take a look.
Same-day service is our standard across Mesa, Gilbert, Chandler, Queen Creek, Scottsdale, Phoenix, and the rest of the Valley.
Due for a check-up while we’re out? Our full tune-up is $39.99 — same price in every city we serve.
Look up your exact opener
Diagnostic codes, programming steps, and learn-button colors all change by brand and by model. We keep a page for every opener we service — pick your brand below, find your model in the list, and its page has the diagnostic codes, the programming guide, and the manufacturer’s manual.
Your model number is on a sticker on the side or back of the motor housing, and it’s usually printed on the inside of the light cover too.
Straight to a model page: LiftMaster 2420L · Chamberlain B4603T · Genie 7155D
Questions we get asked about this
Aligned isn't the same as working. Check that both lights are actually lit and steady — a sensor can point perfectly at its partner and still be dead from a broken wire, a failed unit, or a lens so clouded it can't pass the beam. If both lights are genuinely solid and it still won't close, you're most likely looking at a travel limit or close-force setting, something binding in the track, or the door itself being out of balance.
There isn't really a reset for this — a door that won't close is reporting a real condition rather than glitching. Start with the sensors: clear the path, wipe both lenses, and re-aim them until both lights are steady. If you want to rule out a genuine electronic hiccup, unplug the opener for about 30 seconds and plug it back in. But if the underlying fault is still there, it'll come straight back, and chasing resets just delays finding the actual cause.
Because holding the wall button is the built-in override that bypasses the safety sensors. If the door closes that way and no other way, your opener is telling you plainly that the sensors aren't satisfied — misaligned, dirty, unpowered, or failed. It's a genuinely useful diagnostic, but please don't use it as a workaround. That override exists for emergencies, and while it's engaged nothing will stop the door on a child or a pet.
That's almost always direct sun hitting the receiving photo eye and washing out the infrared beam, which the opener reads as blocked. It's common here — especially on west-facing garages in winter when the sun sits low. A small shade or hood over the receiving sensor usually solves it permanently, or you can swap the two sensors side for side so the receiver faces away from the sun. If neither trick holds, sensor replacement is a short garage door opener repair.
Usually not. A door that seats and then reverses is being pushed past where the floor is: the opener keeps driving after the bottom seal is already compressed, feels the resistance, and reads it as an obstruction. Sensors would have stopped it before it got there. That one belongs to the travel limits rather than anything on this page — we've written it up in full on the page about a door that keeps going back up.
On LiftMaster and Chamberlain openers, ten blinks is the safety sensor code — the beam is blocked, the sensors are misaligned, or one has lost power. It's the most common code these units produce. Clear anything in the path, wipe both lenses, and re-aim until both indicator lights are solid.
Holding the button puts the opener into constant-pressure mode, and in that mode the sensor system is deliberately bypassed — the door will close through a broken beam, and it will keep closing while your finger is down. That's the whole point of the feature: it exists to get a door shut when a sensor has failed, on the assumption that you're standing there watching the opening. It's not a setting to live with. Anything in the doorway is relying entirely on you seeing it.
Please don't. Beyond the obvious risk, since 1993 federal rules (16 CFR Part 1211) have required every residential opener made in the US to have secondary entrapment protection — in practice that means photo eyes, which is what essentially every manufacturer fits, and openers built to the UL 325 standard won't operate normally without them anyway. If a sensor has failed, replacing the pair is a straightforward job — cheaper and far less trouble than the alternative.
Two different faults produce this. If it reverses partway down, something is breaking the sensor beam or obstructing the track mid-travel. If it reverses only after touching the floor, that's a travel limit or down-force setting. The distinction matters, because they're fixed in completely different places.
Absolutely, and it's the possibility people most often miss. The springs carry nearly all the door's weight — the opener only nudges it. When a spring fatigues or breaks, the opener suddenly faces a 150–250 pound door and refuses rather than destroy itself. Pull the emergency release and lift the door by hand: a healthy door feels like about ten pounds and stays put wherever you stop it. If yours is heavy or slams down, it's the springs, and no opener adjustment will fix it.
It depends entirely on which of the causes above it turns out to be — a sensor alignment and a spring replacement are very different jobs. That's why we don't publish a number we'd only have to walk back. What we can promise is a written quote before any work starts, and an honest answer if we think the better move is replacing the opener rather than repairing it.
Usually lock mode. Most wall panels have a Lock or Vacation button that disables all remotes, and it's easy to press by accident — hold it for a couple of seconds to toggle it off. If that's not it, try a fresh remote battery, then reprogram the remote at the opener's Learn button. If it works up close but not from the driveway, check that the opener's antenna wire hangs down freely, and consider whether LED bulbs in the opener are interfering.
Sometimes, but it's well down the list. A logic board that has lost its sensor circuit will refuse to close and report a code, and an opener with a stripped drive gear will run without moving the door. Both are real. But the great majority of won't-close calls we run are the beam, the wiring to it, or the travel and force settings — and those are the three things worth eliminating before anyone starts talking about a new opener.
Where this information comes from
- DASMA Technical Data Sheet #190 — Factors Affecting Spring Cycle Life — extreme heat and its effect on spring life
- DASMA Technical Data Sheets (full index) — industry standards for door and opener systems
- UL 325 — the safety standard governing entrapment protection and auto-reverse on residential garage door openers — photo eyes have been required on new openers sold in the U.S. since 1993
Where we come out
We’re a family-run shop based in Mesa, and we cover the whole Phoenix metro. Same-day service is our standard — pick your city, or just call (602) 935-9766 and we’ll find the soonest slot that works.
Not sure if you’re in range? Give us a call — if we can’t get to you, we’ll point you to someone who can.
Want us to just take care of it?
If you’ve worked through this and you’d rather have someone who does this every day handle it — that’s us. Tell us what your garage door opener is doing and we’ll come diagnose it properly.
- Same-day service is our standard
- Family-owned right here in Mesa
- Straight answers — we’ll tell you if it’s not worth fixing
- Written quote before any work starts