How to Troubleshoot a Garage Door

If the garage door won't open or close, begin with these garage door troubleshooting steps:

• Make sure the opener is plugged in and the garage circuit breaker is in the correct place.
• Make sure your door has not been manually locked by mistake.
• Replace the batteries of the keypad or remote control.
• Confirm that you’re within the recommended range and position when using garage door remotes.
• If you need to open a garage door that stays closed, pull the emergency release cord – usually a length of red rope hanging from the trolley. The cord disconnects the trolley, allowing you to open the door manually.

Safety Tip: If you pull the release cord when the door is in the open position, it could come crashing down. Call a garage door service instead.

• When garage door openers are plugged in, but the door does not close or open, there may be a problem with the external controls, such as the wall switch, keypad or remote control.
• Test all of the controls to determine if only one is faulty but the others work.
• If the garage door opener motor has an antenna for the remote control, make sure that it is undamaged and in the correct position.
• If the remote control has batteries and is being used within the correct range, it may need to be replaced. Universal garage door remote controllers can work on many openers.
• Reprogram or reset the remote control or keypad by consulting with the respective owner's manual.
• If the remote control or keypad work but the wall switch does not, the switch or button itself may be faulty or need new wiring.

• If the garage door won’t close all the way, or closes and opens immediately, there may be an issue with the safety sensors, which are designed to prevent the door from closing on a person or object.
• Make sure that the safety sensors are pointing at each other and in proper alignment – use a level if needed.
• Use a soft cloth and a mild cleaner to gently clean the sensors to make sure no dirt is covering the eye. Softly wipe away moisture and residue, taking care to avoid scratching the sensors.
• Make sure no toys, flower pots or other objects are obstructing one or both of the sensors. Each sensor should have a small light that shines when there are no obstructions.

Tip: Strong, direct sunlight can interfere with sensor performance, so make sure sensors have sun screens or are placed in shade.

As a safety feature, a garage door opener motor is equipped with switches that specify when the motor should stop while opening and closing. If the close-limit or open-limit switches are set improperly, they can prevent the door from closing or opening all the way.

The garage door opener motor usually has a lever or screw feature that controls the limit switches. Adjust according to manufacturer’s instructions until the door opens and closes to the desired places.

• If the garage door opener is receiving power but still not operating properly, it could have a mechanical failure.
• If the door won’t open but the engine sounds like it's running, the main gear drive may have broken and need replacement.
• If the trolley carriage moves but the garage door doesn't, one of the components of the carriage is broken and needs replacement.
• If nothing happens at all, the circuit board of the garage door opener motor likely needs replacement.
• If you have a chain drive garage door opener, make sure that the chain has the correct tension: too little tension can cause the chain to slip the sprocket and fail to pull the trolley.

Your garage door’s cables and torsion springs are key components in lifting the door. The garage door springs and cables can eventually wear out, and broken ones can prevent the door from opening. Replacing a spring can be dangerous, so consider calling a garage door technician.

• If the motor and controls work and the door still won’t open, there may be a problem with garage door parts such as the tracks and rails.
• The garage door opens and closes along a metal track that can malfunction if it goes out of alignment. Realign the track by loosening the screws that hold it to the frame. Use a rubber mallet to gently tap the track back into the correct position, using a level if needed to confirm straightness. Tighten the screws until the track is aligned.
• If the steel or nylon rollers within the tracks are damaged or rusted, they can prevent the door from moving. Replace as needed.
• Use a white lithium grease or garage door lubricant on the rail that runs along the trolley carriage. Too much friction can prevent the door from opening smoothly.

Tip: In colder climates, lubricate the rail with white lithium grease, especially in wintertime.