The most common reasons a garage door won’t close include misaligned safety eyes, obstructions in the opening and broken door components. Problems that occur during the down cycle are usually due to user error versus opener malfunction.

Nothing is more annoying than pressing your remote control button, only to see the door start down and reverse right back up again. Even doors that have been professionally installed and maintained are prone to intermittent problems closing.

Use this guide to troubleshoot an overhead door that won’t close. We’ve listed 20 of the most common reasons that doors won’t shut along with some quick fixes you can try.



Why is my garage door reversing back up?

Overhead doors start down and reverse back up when the opener thinks their is an obstruction in the way. This is likely due to the safety eyes being blocked, the maximum force sensor being activated or an obstruction actually in the door path.

Blocked photo eyes trigger the door to reverse for safety reasons – preventing a small child or animal from being crushed under the door. If the safety eyes fail to work the maximum force sensor serves as a backup. If more force than usual (excessive) is needed to close the door it will also reverse back up to prevent crushing the obstruction.


Why is my opener light flashing?

Garage door openers have built in troubleshooting codes to help you diagnose what is wrong. The number of blinks, clicks and light bulb flashes corresponds to a specific problem. This diagnostic code system was created for all Chamerlain Liftmaster openers, but varies by manufacturer.

An opener light that blinks 10 times means the safety eyes are blocked, blinded or out of alignment. Defective photo eyes, loose wiring or obstructions in the door path can cause the opener to flash 10 times.


How do I close the garage door manually?

If you can’t get your garage door to close with the opener you still have a few options. Make sure nothing is in the path of the opener or stuck in the track. Then press and hold the wall button until the door closes completely then release the button. Holding the wall button down overrides the safety reverse system.

Note: Pressing and holding the remote transmitter or keypad won’t work – only the wall control button.

A second object includes disconnecting the garage door opener trolley from the door. Pull the red release cord until the trolley disengages. Then you can manually close the door by hand by pulling it down. This method was originally designed for door operation during power outages, but can also be used for stubborn openers that won’t close the door.


How long do opener safety sensors last?

Most garage door openers usually last between 10-20 years, but several components like safety beams can break faster. Safety beams should last as long as the opener if they aren’t hit or overly exposed to moisture.

Since photo eyes are installed on the vertical track 4-6 inches off the floor they come into contact with moisture. When water gets inside the casing the internal components go bad. This is especially a concern  for cold and rainy climates where snow, ice and heavy rainfall occur.

Safety eyes also tend to get hit by childrens toys, tools and trash cans. Contact over time will damage the plastic casing, wiring and internal parts. Store items in the garage away from the photo eyes and encourage children to stay away from the beams when playing.


1. Safety Sensors Malfunctioning

Safety Sensor Sending Eye Amber Light
Safety Sensor Receiving Eye Green Light

A garage door that reverses in the opening is most commonly caused by malfunctioning safety sensors. Also called photo eyes or safety beams, these devices alert the opener to stop and reverse when something trips the sensor. Unfortunately, several things can also cause them to falsely signal that an obstruction in the door path.

Monitoring and inspecting the photo eyes is the best place to start when troubleshooting. Problems that originate from the safety beams are often quick fixes. Lets take a look at the main problems that are caused by the photo eyes.


1.1 Check For Proper Alignment

An invisible laser beam runs across the opening of your garage from one photo eye to the other. If the safety eyes get knocked out of alignment the beam from the sending eye won’t hit the receiving eye. When the eyes are knocked out of alignment the glow lights will turn off completely, blink or flash.

Aligning the eyes is a matter of adjusting the mounting brackets and wing nuts until the eyes are pointed at each other.  A successful alignment results the green, red or amber glow bulb lighting up.


1.2 Unblock The Photo Eyes

Door openings should be free and clear or all obstructions. Is it possible something is blocking the path of the photo eyes? During my time as a service manager there were always cases where our repair technicians were called out only to discover a trash can or flower pot blocking the safety sensors. Garages that are used for storage are especially prone to blocked photo eyes.

Cardboard box flaps can flip down and plastic bags can blow around from the wind. Look for obstructions 4-6 inches off the floor across the entire width of the door opening – look for items that could shift while the door is closing.


1.3 Clean The Lens Covers

Safety Sensor Dirty Lens CoverYour garage door naturally acts as a backstop for debris. Over time the lens covers of your safety eyes can become clouded from contacting dust, leaves and cobwebs. Moisture can also get inside the safety beam casing if it isn’t seal properly causing a film buildup – just like the headlights on a car.

Cloudy dust covered lens covers block the beam of light from hitting the internal sensors. Use a damp cloth to clean both the inside and outside plastic lens covers. as part of seasonal garage door maintenance.


1.4 Sunlight Blinding The Receiving Eye

Does your garage door only have problems closing during sunset or sunrise? If so, sunlight could be the source of the problem. Sunset and sunrise tend to coincide with the majority of garage door use since most people work day hours – leaving in the morning and coming back home at night. As the sunlight enters your garage at the right angle the receiving photo eye can get blinded.

Safety beams are interchangeable to switching the receiving eye to the opposite side could fix the issue. If that doesn’t work you could also consider installing a sun shield to prevent direct sunlight from hitting the lenses. A simple cardboard tube-roll or a more professional solution like the Liftmaster 41B873 Sunshield can block direct sunlight exposure.


1.5 Light Flashing Diagnostic Code Chart

This chart is valid for newer Chamberlain Liftmaster openers that have UP and DOWN travel arrows (not dials) on the back of the motor casing. Most issues come from obstructions in the door path, broken springs, stripped nylon gears, loose wiring, misaligned sensors or improper door balance.


Up Arrow FlashesDown Arrow FlashesSymptomSolution
11Door won’t close. Light bulb flashes.Safety sensors not installed, connected or loose wiring. Check for loose or cut wires.
12Door won’t close. Light bulb flashes.Wires reversed or shorting out. Check connection points, staples or replace wiring.
13Wall control won’t function.Short in wiring or defective wall control. Check connection points, staples or replace wiring.
14Door won’t close. Light bulb flashes.Safety sensors misaligned or obstructed. Align sensors making sure glow lights are on (not flickering) Check for objects in the door path.
15Door starts down (8” / 20cm) stops or reverses back up.Check the door balance. Look for binding or track obstructions. Replace travel module if necessary.
15No movement. Just a single click.Check door balance. Look for binding or track obstructions. Replace logic board if necessary.
15Opener makes humming noise and the door doesn’t move.Check the door balance. Look for binding or track obstructions. Replace motor if necessary.
16Door stops then starts drifting.Check the door balance adjusting spring tension as necessary. Re-program travel settings.
21-5No movement or sounds.Replace logic board if necessary.
32Unable to program travel settings or retain stopped position.Check travel module – replace if necessary.
41-4Door is moving – stops or reverses.Check door balance. Look for binding or track obstructions. Reprogram travel setting.
45Door starts down (8” / 20cm) stops or reverses back up.Unbalanced door or communication error with travel module – replace as needed.
46Door won’t close light flashes.Safety sensors misaligned, obstructed or loose wiring. Make sure LEDs aren’t flickering or off.


2. Pinched Or Loose Photo Eye Wiring

Safety Sensor Wire NutsPhoto eyes rely on low voltage wiring to provide power to both the safety beam and glow lights. Bell wire (2 wire T-stat wire 22 gauge) is used for both the photo eyes and wall controls. These wires can come loose if hit by an object or from vibration over time. The two points of contact to monitor are the back of the opener and the back of the photo eye.

Wiring can also get pinched if hit toys or tools in the garage. Another common problem is a staple or tack pinching the wiring too tight to the drywall. Its generally better to run garage door opener wiring through conduit as opposed to stapling it into drywall. Always check for loose or pinched low voltage bell wire when troubleshooting a door that won’t close.


3. Stripped Nylon Drive Gear

Garage door openers have a nylon drive gear that is designed to fail when excessive force is needed to operate the door. Stripped gears are often the result of running the door with a broken spring, a door frozen to the ground or just plain old age. In any case a drive gear with stripped out teeth won’t be able to operate the door.

Most homeowners report hearing a humming noise coming from inside the unit as evidence as of a worn out gear. Further confirmation comes in the form of white nylon shavings inside the case of the opener. You can usually remove the outer casing of the opener by removing a few screws to peer inside. Gears usually strip when opening a door vs closing, but they can also strip out if the door is closed when something is obstructing the track.


4. Interference With Radio Frequency Signal

Liftmaster is working hard to improve your remote signal range and reliability with innovations like WIFI door operation, tri-band signals and Homelink connectivity. Unfortunately, older openers and remotes are still prone to RF interference. A while back I wrote an extensive article highlighting potential sources of interference and how to boost your signal called –  Top 5 Ways to Increase Garage Door Remote Signal Range

Common household items like lights, deep freezers and even kids gaming systems can cause all sorts of problems with your transmitter signal. Eliminating the sources of interference (Light Bulbs), changing frequencies, installing MyQ and extending your antenna can all help combat your remote failing to communicate with the openers logic board.


5. Reprogram Remotes And Keypads

Transmitters and wireless keypads are linked to your garage door opener through the receiver and logic board. The “learn” or program button on the back of your unit allows you to sync devices to that particular opener. If someone were to press and hold down the learn button, everything linked to that opener would be erased. Power surges from near-bye lightning strikes have also been known to reset circuit boards.

If you press your remote control and the door doesn’t move at all, your transmitters could be the source of the problem. Reprogram your remote and wireless keypad to your opener – following the instructions in your owners manual.


5.1 Replace Dead Batteries

Remote and wireless keypad batteries usually last a long time, but will eventually need to be replaced. If a button gets stuck down or is engaged the battery will die extremely fast. Cold weather also tends to wear down batteries so its best replace them before winter. Most batteries are easily found at local stores. To figure out what battery is needed you can take off the cover of the remote.

Installing the Liftmaster MyQ system is one way to eliminate the possibility of dead batteries since your smartphone will control the door vs a handheld remote. In the event of a power outage the Liftmaster battery backup should also be replaced. You can check the date of manufacture sticker or listen for beeping to indicate a dead battery backup.


6. Bad Opener Circuit (Logic Board)

One of the most expensive repairs associated with a door that won’t close is a burned out logic board. The boards serve as the brains of the unit, directing critical functions like a computer. Power surges caused by lightning strikes are the most common reason for a damaged circuit board. Once the board has been damaged the unit may function erratically or not at all. If your opener is old enough (>10 years) it is often more economical to replace the entire unit as opposed to replacing just the board.

You may want to consider installing a plugin (point of use) surge protect like the Liftmaster 990LM or even a built in (whole house) protection system to protect electronics in your home. These safety measures won’t prevent all power surges. but layering them as a combination will decrease the chances of high voltage destroying the circuit boards.


7. Adjust Opener Travel Limits And Forces

When you purchase or repair a garage door you will need to program the units travel limit and force settings. These dials or arrows are located on the back of the opener casing. Adjust the force and travel in small increments of 1-2 positions, testing the door periodically. Never crank up the dials – doing so could damage your garage door opener or top door section.

Travel limit settings tell the opener how far it should open and close. The down cycle limit would naturally be contact with the floor and the open cycle limit would be when the bottom of the door is just below level with the header.

Force settings tell the opener how much force it should use to pull the door open and push the door closed. A properly balanced residential garage door can be opened and closed with less than 15 pounds of force. One of the worst mistakes made by homeowners is inching up the force settings. On older units forces are set by a dial numbered 1 to 9, while new units often have built automatic force recognition.

If your garage door won’t close and you have ruled out photo eyes issues and obstructions, then you might want to consider increasing the down force. Having to increase the opener force is a sign of an underlying issue with the balance of the door.

If you have recently replaced your torsion springs there is a good chance the door isn’t properly balanced. Using too much force will put excess strain on opener components like the nylon drive gear.


8. Disengage Lock Button

Most garage door openers have a master lock button feature. This button disables all remote transmitters, keypads and MyQ enabled controls from operating the door. This feature is useful if you don’t expect to use the door for long periods of time – like going on a vacation. However, this feature can be accidentally enabled since it is usually next to light buttons and other operational buttons.

Make sure you have not accidentally hit this button by checking your display screen or pressing the button to see if it has been disabled. While this button is usually enabled with the door in the closed position, it could also get hit with the door open.


9. Opener Trolley Disconnected

Garage doors can be manually operated by disconnecting the opener trolley or J arm – incredibly useful during power outages. If you have an automatic opener installed it can be disengaged by pulling the red emergency release cord. A disconnected opener trolley won’t be able to pull or push the door until it reengages. You could also disconnect the “J Arm” from the garage door opener attachment bracket by removing the cotter pin to achieve the same goal.

If your door won’t close there is a chance that someone pulled the red release cord or disconnected the J arm assembly. You can easily identify this by inspecting each part. You can re-attached the trolley by pressing your wall control or remote transmitter. The trolley will automatically travel up and down the rail to reconnect itself. Reconnecting the J Arm is just a matter of attaching it to the opener attachment bracket and re-installing the clevis pin.


10. Disrupted Power Source

Residential garage door openers plug into standard (120v) wall outlets as a power source. If your garage door opener and photo eye glow lights aren’t lighting up check to make sure the power cord is plugged into the wall outlet. Next, check your circuit breaker box to make sure the garage circuit breaker hasn’t been tripped. This happens when a circuit is attempting to draw a greater electrical load than its intended capacity.

Most tripped circuits are the result of overloading – having too many devices drawing current at the same time. if you have several devices like refrigerators, deep freezers or sound systems plugged in, running the opener could trip the circuit breaker.

Power disruptions to your opener could also be caused by a short circuit –  when a hot wire (black) touches a neutral wire (white). A short circuit is possible if you have unplugged extra devices, reset the circuit breaker and it instantly trips again. If you suspect a short its best to call a licensed electrician to inspect your electrical wiring.


11. Misaligned Bent Obstructed Tracks

The tracks or “guide rails” should be level, even and plumb to ensure smooth operation. Tracks that are improperly installed or have been hit (bent) by a vehicle can cause problems with door operation.

Tracks should be set wide enough that the rollers move freely, but not too wide that the rollers have the potential to fall out. Tracks can also be angled outward or outbalanced causing the door inch up and down during operation.

Tracks can also become obstructed causing the rollers to grind and catch during travel. The horizontal and vertical track pieces form a joint near the top of your door opening. If track is bent or obstructed this joint gets too far out of alignment – causing the door to catch as it travels through the curved radius.


12. Bent Door Sections

Are your garage door panels bent? If your sections have been hit or are sagging in the middle you might have issues with the door closing. All doors have joints that must line up correctly to close the door in a smooth manner.

Overhead doors have two types of joints – tongue & groove is the most popular followed by shiplap. Tongue and groove joints offer a tighter door seal, but are more sensitive to misalignment. A door that has been hit with this type of joint have trouble closing due to the tongue joint not lining up correctly with the groove. This results in the all too familiar catching and popping noises.

Poorly manufactured older doors tend to sag in the middle. Warped panels cause problems with joint alignment as well. This can be fixed by installed horizontal bracing called struts, which supports the weight of the door panels across the entire width of the panel. Alternatively, you can consider purchasing a double wall insulated door that is more resistant to warping.



13. Broken Cables Off Drums

Garage doors work on a counterbalancing system made up of springs transferring force through drums and cables to the bottom brackets. If the garage door cables slip off the grooves of the drums or break this counterbalancing force is lost. This results in you or your opener having to lift the entire weight of the door verses a tiny percentage.

Cables that have slipped off the drums or are broken can cause a tangled mess, preventing your door from closing. This results in a dangerous situation where your garage door could slam to the floor if an opener isn’t being used.


14. Broken Hinges Or Rollers

Hinges allow the door sections to move around the curved radius of the track. The roller carrier section of the hinge allows the stem to rotate freely just like the bearings inside the wheel. If a hinge breaks or falls off the door will be unbalanced leading to issues with the opener force settings.

Broken hinges and rollers can also catch on parts of the track, even causing rollers to fall out of the guide rails. After this happens your door section may bend lower on one side of the door causing uneven operation. Broken hinges and rollers can cause serious (more expensive) problems if they aren’t fixed right away. Never attempt to close the door using your opener if the door has broken parts.