Garage Door Won't Open? Every Cause, In the Order We Check Them
A door that won't open is more urgent than one that won't close — usually because a car is trapped behind it. The good news is that this symptom narrows down fast, and the question that does the narrowing is simply what does the opener do when you press the button? Dead silence points one direction. A motor that runs while the door sits still points somewhere completely different. A motor that strains and gives up points at the door rather than the opener. This page works through all of them in the order we do on a service call, and it starts with getting your car out.
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.
If you need the car out right now
Before troubleshooting anything: you can disconnect the door from the opener and lift it by hand. But read this first, because one situation makes that dangerous.
- If you heard a loud bang recently, look at the spring above the door before pulling anything. A visible gap in the coil means the spring is broken.
- With a broken spring the door weighs 150–250 lb with nothing holding it up. Pulling the release lets that weight go.
- Never pull the emergency release with the door partly open if you suspect a spring problem — it can come down hard.
- A loose or frayed lift cable means the same thing: the door's weight isn't being carried.
- If the door is crooked in its opening, don't force it — you'll jam it harder.
The red cord disconnects the door from the opener so you can move it by hand. That's safe on a healthy door, where the springs carry the weight and it feels like about ten pounds. On a door with a broken spring it is not — you'd be taking hold of the full weight with no counterbalance. If in doubt, leave it and call us; we'll get your car out. Getting a car out from under a door in that state is ordinary 24-7 emergency garage door repair work.
Call (602) 935-9766What to check in the next 10 minutes
Five checks, in this order. Most no-open calls are solved before you get to the end.
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1Press the wall button and listen carefully
Total silence, a click, a hum, or the motor running normally — these are four completely different diagnoses. This is the single most useful thing you can tell us on the phone.
You’ll know it worked when: You can describe exactly what you hear when you press the button.
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2Check the opener actually has power
Does its light come on? Openers are very often on a GFCI outlet, and a tripped GFCI kills the opener while the rest of the house is fine. Check the outlet and your breaker panel.
You’ll know it worked when: The opener light works and the outlet is live.
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3Look for the lock indicator on the wall panel
Most modern wall controls have a Lock or Vacation button that disables all remotes. Easy to press by accident. Hold it a couple of seconds to toggle it off.
You’ll know it worked when: The lock light is off.
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4Try both the wall button and a remote
If the wall button works and the remote doesn't, it isn't really a won't-open problem — it's a remote problem, and that's a much smaller job.
You’ll know it worked when: You know whether it's everything, or just the remotes.
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5Look at the door itself for anything obvious
A broken spring with a visible gap, a cable hanging loose, a roller out of its track, or the manual slide lock engaged. Any of these explains it immediately.
You’ll know it worked when: The springs look intact, cables are taut, and nothing is visibly out of place.
The question that splits this in half
Everything below follows from this one observation, so get it right before you go further.
If the motor runs and you can hear grinding or see plastic shavings on the floor beneath the opener, stop pressing the button — you're finishing off a drive gear that might still be salvageable.
Which version is yours?
Match what you're seeing.
No power reaching the opener. Start at the outlet and the breaker.
Jump to that fix ↓It has power but isn't accepting the command. Lock mode, wall button, or remote.
Jump to that fix ↓Not a door problem at all — a remote or lock-mode problem.
Jump to that fix ↓Trolley disconnected or drive gear stripped. Very distinctive.
Jump to that fix ↓Usually a failed capacitor. The motor is trying and can't start.
Jump to that fix ↓The opener is meeting resistance it won't push through. Door or track.
Jump to that fix ↓Broken spring. The opener is refusing rather than destroying itself.
Jump to that fix ↓What actually lifts your door
This surprises people, and it's the key to understanding most no-open faults: your opener does not lift the door. The springs do.
A residential garage door weighs somewhere between 150 and 250 pounds. The torsion spring above the opening — or the extension springs along the tracks on older setups — stores enough energy to counterbalance almost all of that. On a properly balanced door, the weight you'd feel lifting it by hand is around ten pounds. That's the whole point of the counterbalance system.
The opener's job is just to supply that last ten pounds of push and to control the travel. Which is why a half-horsepower motor can move a quarter-ton door for twenty years without complaint — and why, the moment a spring breaks, that same motor is suddenly asked to lift the entire weight on its own and simply can't.
Modern openers are built to recognize that and stop rather than burn out. So “motor runs, door doesn't move” is frequently not an opener fault at all. It's the opener correctly declining to destroy itself.
The other thing worth knowing is the trolley — the sliding piece on the rail that actually pulls the door. The red cord disconnects it, so you can move the door by hand during a power cut. Once disconnected, the opener will run its whole cycle happily with nothing attached.
So: silence means it isn't getting the message or the power. Running means it is, and something downstream is wrong. Straining means the door itself needs attention.
Match your symptom
Find the row that matches what you're hearing and seeing.
| What you’re seeing | Most likely cause | How urgent | Who should fix it |
|---|---|---|---|
| No sound, no light, nothing | No power — unplugged, tripped GFCI, or breaker | Fix today | You can do this |
| Light works, button does nothing | Lock mode on, or failed wall button | Fix today | You can do this |
| Wall button works, remote doesn't | Remote battery, lost programming, or lock mode | This week | You can do this |
| Single click, no motor | Failed capacitor or seized motor | This week | Call a pro |
| Motor runs full cycle, door still | Trolley disconnected from the door | Fix today | You can do this |
| Motor runs, grinding noise, plastic bits below | Drive gear stripped | Stop using it | Call a pro |
| Motor hums, nothing turns | Capacitor failed | This week | Call a pro |
| Lifts a few inches then stops | Door binding, or too heavy for the opener | Stop using it | Call a pro |
| Loud bang earlier, now won't lift | Broken torsion spring | Stop using it — call today | Call a pro |
| Door is crooked and jammed | Cable off a drum, or door off track | Stop using it — call today | Call a pro |
| Worked yesterday, dead after a storm | Surge damage to the logic board | This week | Call a pro |
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 opener has no power
Basic checkStart here, because it's common and it's free to check. Openers are frequently plugged into a GFCI outlet, and a GFCI can trip from a fault anywhere on its circuit — often something else entirely, like a pressure washer or a fridge in the garage. When it trips, the opener goes completely dead while the rest of the house carries on normally, which is why people assume the opener has failed.
How you can tell: No light, no sound, no response of any kind. Nothing at all when you press the button.
- Check the opener is actually plugged in — ceiling outlets get bumped by ladders and long loads more often than you'd think.
- Look for a GFCI outlet in the garage and press its Reset button. It may be the outlet the opener is in, or another one upstream on the same circuit.
- Check your breaker panel for a tripped breaker on the garage circuit and reset it.
- Test the outlet with something else — a lamp or a phone charger — to confirm it's actually live.
- If the outlet is live and the opener is still dead, the fault is inside the unit.
You’ll know it’s right when: The opener light comes on and it responds to the button.
Lock mode is on, or the wall button has failed
Basic checkMost modern wall controls have a Lock or Vacation button that deliberately disables every remote — a real security feature that's also very easy to press by accident, and endlessly interesting to children. Separately, a wall button whose contacts have failed or whose wire has shorted can stop the opener responding to anything.
How you can tell: The opener has power and its light works, but pressing the button does nothing. For lock mode there's usually a small lit indicator on the panel.
- 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.
- 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, briefly disconnect its two wires at the opener terminal and try a remote. If the remote then works, the button or its wiring is the fault.
- Check the wall button's wire run for damage, especially anywhere it passes behind something mounted to the wall.
You’ll know it’s right when: The lock light is off and the opener responds to both the wall button and a remote.
The remote has lost programming or its battery
Basic checkStrictly this is a remote problem rather than a door problem, but people describe it the same way. Rolling-code openers can lose a remote's registration after a power surge or a board reset, and remote batteries fade gradually — giving reduced range before they give nothing at all.
How you can tell: The wall button opens the door perfectly. The remote does nothing, or only works from a few feet away.
- Change the remote battery first — usually a CR2032 or A23. 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.
- Press and release Learn — do not hold it, holding erases every remote you own — 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 the opener's antenna wire hangs down freely and hasn't been cut or tucked away.
- If range dropped after you changed the opener's bulbs, try a different bulb — LED bulbs are a well-known source of radio interference.
You’ll know it’s right when: The remote works reliably from the end of the driveway.
The logic board has failed
High risk — call a technicianThe board is the opener's brain, and when it fails the unit typically goes unresponsive despite having power. Surges are the usual cause here, which is why we see a cluster of these after monsoon storms. Heat doesn't help either — the board sits near the ceiling of a garage that runs extremely hot in summer.
How you can tell: The outlet is confirmed live, lock mode is off, the wall button is ruled out, and the opener still does nothing — or it behaves erratically, responding sometimes and not others with no pattern.
The trolley is disconnected from the door
Basic checkOne of the most satisfying fixes on this list because it takes thirty seconds. The 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 runs its entire cycle perfectly happily with nothing attached — motor humming, chain or belt moving along the rail, door sitting exactly where it was. People pull it during an outage and forget, or a tall vehicle catches it on the way in.
How you can tell: The motor runs its 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 first. This matters — re-latching a partly open door means it can drop as it connects.
- Pull the red cord toward the door rather than straight down, which resets 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 fully 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 drive gear has stripped, or the capacitor has failed
Hands-on — moderate riskTwo different faults with a similar presentation. The drive gear is a nylon component inside the opener that transfers motor rotation to the chain or belt — it wears out, and it wears out much faster on a door that's been hard to lift, which is why a stripped gear often means there was a spring problem first. The capacitor gives the motor its starting kick; when it fails the motor hums but can't turn.
How you can tell: For a stripped gear: motor runs, nothing moves, often a grinding noise, and sometimes white or gray plastic shavings on the floor beneath the opener. For a capacitor: the motor hums or buzzes but nothing rotates at all.
- Look on the floor directly under the opener for plastic shavings — that's a fairly conclusive sign of a stripped gear.
- Listen carefully: grinding suggests the gear, an electrical hum with no movement suggests the capacitor.
- Stop operating it either way. Continuing to run a stripped gear grinds away what's left, and running a humming motor overheats the windings.
- Check the door's balance by hand once it's disconnected — if the door is heavy, that's why the gear went, and replacing the gear alone will just do it again.
You’ll know it’s right when: You've identified which of the two it is and stopped cycling the opener.
The door is binding in the track
Hands-on — moderate riskIf the opener lifts the door a few inches and then stops or reverses, it's meeting resistance it's been told not to push through. A bent track, a seized roller, a loose bracket, or a hinge that's pulled away will all do it — and the door will usually stop at the same point every time, which is your best clue.
How you can tell: It starts up, gets a few inches, and gives up. Often with an audible scrape or thunk. Usually the same spot every attempt.
- Note exactly where it stops — that's where to look.
- With the door down, inspect both tracks at that height for dents, gaps between sections, or brackets pulling away from the wall.
- Spin the rollers at that point with your fingers. One that won't turn freely is worn and dragging.
- Check the manual slide lock on the door — an engaged lock will stop the door dead and it's easy to overlook.
- Look at the hinges at that section for cracks or elongated bolt holes.
- Tighten any obviously loose track brackets and lag bolts.
You’ll know it’s right when: The door runs the full travel without hesitation or noise.
A spring has broken
High risk — call a technicianThe most common reason a door genuinely won't open, and usually the most obvious once you know what to look for. The springs carry nearly all the door's weight. When one breaks, the opener is suddenly asked to lift 150 to 250 pounds on its own — and a modern opener will refuse rather than destroy itself trying. Older or less sophisticated openers will try, and strip their drive gear in the process, which is how one problem becomes two.
How you can tell: Look at the spring on the shaft above the door: a broken torsion spring shows a clear gap of an inch or two in the coil. Often there was a loud bang, sometimes hours or days before anyone tried the door. On extension-spring setups, look along the tracks for a spring that's gone slack or come apart.
What your opener is telling you, by brand
LiftMaster & Chamberlain
The opener light flashes a diagnostic code. Worth counting before you start pulling things apart.
| Light blinks | What it means | What to do |
|---|---|---|
| No light at all | No power reaching the unit | Check the outlet, GFCI and breaker — cause 1 |
| 1 or 2 blinks | Safety sensor wire disconnected or shorted | Check both sensor wires and terminals |
| 3 blinks | Door control (wall button) wire shorted | Disconnect the wall button and retest — cause 2 |
| 5 blinks | Motor overheated or motor circuit fault | Let it cool 15–30 min; if it repeats, call us |
| 6 blinks | Motor circuit failure | Service call — the motor or board has failed |
| Light on, no response to button | Lock mode, wall button, or board | Causes 2 and 4 |
Genie
Genie reports through the powerhead and the Safe-T-Beam LEDs.
| What you see | What it means | What to do |
|---|---|---|
| No power light | No supply to the unit | Outlet, GFCI, breaker — cause 1 |
| Both Safe-T-Beam LEDs steady red | Travel limits lost or never set | Re-run the limit-setting routine from your manual |
| Motor runs, door still | Trolley disconnected, or stripped gear | Causes 5 and 6 |
| Clicks but won't start | Capacitor or motor fault | Service call — cause 6 |
Craftsman & older units
Mostly Chamberlain-built and sharing those codes, but genuinely old units often report nothing at all.
| What you see | What it means | What to do |
|---|---|---|
| No diagnostic light | Pre-diagnostic-era opener | Work through the fork above — motor running or not |
| Hums, won't turn | Capacitor failure — common on older units | Service call — cause 6 |
| Runs but grinds | Stripped drive gear, common at this age | Stop using it, and check door balance too |
What you’ll need if you’re doing this yourself
- A flashlight — for inspecting the spring above the door and the track
- A fresh remote battery — usually CR2032 or A23 — rules out the cheapest cause in seconds
- A stepladder — for reaching the opener head, the Learn button and the antenna
- A known-good lamp or charger — to confirm the outlet is actually live
- A scrap 2x4 — for the safety reversal test once it's working again
Things not to do — and why
The release disconnects the door from the opener. On a healthy door the springs still hold the weight. On a broken spring, nothing does — and you've just taken hold of 150 to 250 pounds with no counterbalance.
Every attempt against a heavy door grinds the nylon drive gear a little further. That's how a spring repair becomes a spring-and-opener repair.
They store enough energy to cause serious injury, and they're wound tightest exactly when the door is down. This is the single most common way homeowners get badly hurt on a garage door.
A breaker that trips immediately is doing its job. Something is drawing fault current, and that's an electrician's problem.
A quick press starts programming. Holding it for several seconds erases every remote, keypad and in-car button you've ever paired.
The door can drop as the trolley latches. Close it fully by hand first, every time.
If the door is off track or a cable has come off a drum, forcing it wedges things harder and can bend the track beyond repair. Stop and call.
What we see most in the Phoenix area
Two things drive the no-open calls here more than anywhere else, and both come down to heat.
The first is spring life. Steel fatigues faster with repeated heat cycling, and extreme climate is on DASMA's own list of factors that cut spring cycle life short, and in this valley that translates into springs going before the decade most homeowners are expecting. A spring that might have given ten years in a mild climate often doesn't here — which is why broken springs are such a common cause of a door that suddenly won't open in an uninsulated Arizona garage.
- Springs fail sooner — daily heat cycling in a garage that passes 130°F is hard on steel. Broken springs are our most common no-open cause.
- Storm-season surges — monsoon lightning takes out logic boards. We see a distinct cluster of dead openers after big storms.
- GFCI trips during storms — moisture and surges trip GFCIs, and since openers are often on one, the door goes dead while the house is fine. Always worth checking before assuming the worst.
- Heat on the board — the logic board sits near the ceiling in the hottest part of the garage. Electronics age faster up there.
- Dust in the rollers — fine monsoon silt works into roller bearings and keeps grinding, so friction climbs and doors get harder to lift over a season.
Reducing the odds of being stuck again
Most no-open situations give warning first, if you know what to watch for.
- Do the balance test twice a year — release the door, lift by hand, check it stays where you stop it. This catches a fatiguing spring months before it strands you.
- Listen for changes — a door that's gotten noisier, slower, or more hesitant is telling you something. Problems here announce themselves before they fail outright.
- Lubricate rollers, hinges and the spring annually with a silicone or lithium garage-door product. Less friction means less strain on both spring and opener.
- Fit a surge protector on the opener circuit — cheap insurance for the logic board through monsoon season.
- Know where your GFCI is before you need it. Two minutes now saves an hour of confusion later.
- Replace both springs together when one goes. They're the same age and the second is close behind — doing one is a false economy.
- 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.
How this usually develops
A door that won't open rarely fails without warning. This is the sequence we see.
That last step is the avoidable one. An opener that's been fighting a heavy door for months has usually damaged its own gear by the time the spring finally goes — which is why we always check door balance rather than just replacing the part that broke.
When to call us
Call straight away if you see a gap in the spring, a loose cable, a crooked door, or plastic shavings under the opener. Call if the motor hums without turning, if it strains and stops, or if you've confirmed power and it still does nothing. And if your car is trapped, say so when you ring — we'll prioritise it.
- Work out in the first few minutes whether it's electrical, drive, or door — the three fixes are very different
- Get your car out safely, including a controlled manual lift if a spring has failed
- Test the power supply, wall control, remotes and logic board inputs
- Check the trolley, drive gear, chain or belt for wear and damage
- Release the door and check its balance by hand — the step that catches the real cause
- Inspect springs, cables, drums, tracks, rollers and hinges through the full travel
- Run the UL 325 safety reversal test once it's running again, and show you the result
- Tell you what we found and what we'd do before touching 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, 24-7 emergency garage door repair may be the closer fit.
What this costs to put right
A no-open call covers the widest range of any symptom on this site — it can be a tripped GFCI or a full spring replacement. Here's what determines it:
- Whether it's electrical, drive, or door A reset outlet costs nothing. A stripped gear means parts and labour. A spring is a different job again. Which of the three you're in decides how big the garage door opener repair is before anyone quotes it.
- Which spring your door takes Wire size, length, and whether it's a one- or two-spring setup all matter, and cycle rating affects both price and how long the next one lasts.
- Whether the opener was damaged too A door that's been heavy for months has often chewed the drive gear. Worth checking both rather than fixing one and returning for the other.
- Whether the logic board survived Surge damage to the board is the most expensive single part in most openers.
- The age of the opener Past fifteen years with a failed board or motor, we'll give you an honest view on whether replacement beats repair.
- Whether it's an emergency call-out If your car is trapped and you need us today, that's a different scheduling conversation than booking for next week.
You'll get a written quote before any work starts, and no pressure if you'd rather think about it. If you're due anyway, our full tune-up is $39.99 — 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
Start with what the opener does when you press the button. Silence points at power, lock mode, a remote, or the logic board. A motor that runs while the door sits still points at a disconnected trolley or a stripped drive gear. A motor that strains and gives up points at the door itself — usually a broken spring. Those three branches have completely different fixes.
Pull the red emergency release cord to disconnect the door from the opener, then lift by hand. But check the spring above the door first — if there's a visible gap in the coil, don't. With a broken spring the door weighs 150 to 250 pounds with nothing holding it up, and releasing it means taking that weight yourself. If in doubt, call us and we'll get the car out.
Almost always the trolley has been disconnected from the door — someone pulled the red emergency release during a power cut and it was never re-engaged. Close the door fully by hand, pull the cord toward the door to reset the lever, then run the opener; the trolley will re-latch with a click. If that isn't it, the nylon drive gear inside the opener has stripped, which often shows as plastic shavings on the floor underneath.
A motor that hums without turning has usually lost its capacitor — the component that gives it a starting kick. The motor is trying and can't get moving. Stop pressing the button, because a stalled motor overheats its windings quickly. It's a repair rather than a homeowner fix, but not an especially expensive one.
It's the most common reason a door genuinely won't open. The springs carry nearly all the weight — the opener only adds the last push. With a broken spring, the opener is asked to lift the whole 150 to 250 pounds and refuses rather than destroy itself. Look at the shaft above the door: a broken torsion spring shows a clear gap of an inch or two in the coil.
Two likely culprits. A tripped GFCI outlet — openers are often on one and moisture or a surge will trip it, killing the opener while the rest of the house is fine. Or surge damage to the logic board, which we see a distinct cluster of after monsoon storms. Check the GFCI and breaker first, because that one's free.
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 at the opener's Learn button. Press and release it, don't hold it, or you'll erase every remote you own.
No. A door that struggles is telling you the counterbalance isn't working properly, which means the opener is taking weight it wasn't designed for. Every cycle wears the drive gear further, and a door that's straining can also be one that's about to come down unevenly. Stop using it and get it looked at — the repair gets more expensive the longer it runs like that. Straining doors get worse on their own schedule, so the garage door opener repair is cheaper booked early.
It genuinely depends on which of the causes it turns out to be — a tripped GFCI costs nothing, while a spring replacement is real work. That's why we won't quote a number we'd have to walk back. What we will do is diagnose it properly, give you a written quote before starting, and tell you honestly if replacing the opener makes more sense than repairing it.
Yes — tell us that when you call and we'll prioritise it. Same-day service is our standard, and a trapped car moves you up the list. In the meantime, don't force the door or pull the release if you suspect a broken spring; we'd rather get it open safely than have you fighting it.
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 — entrapment protection and auto-reverse requirements for residential garage door openers — the standard behind the safety reversal test
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