There are many things that can cause a garage door opener to malfunction. Some can be easily fixed; others will require replacing the whole unit. With the exception of the most expensive of garage door openers, the majority are made with plastic parts- which can strip away or break if the door itself isn't in top working condition. Sometimes though, it is all a matter of knowing a few tricks...
Before becoming a garage door technician, I did not give a second thought to how the garage door works, or what the maintenance procedures were...I just knew it went up and then back down when I pressed the button! With a little bit of knowledge, you can prevent a lot of garage door problems from ever happening.
- Safety Eye Misalignment or Malfunction: the safety eyes are the sensors that are located at the bottom of the door on each side (about 6 inches above the floor). They have been mandatory since the early '90s, but if you have an older opener there is a chance it will not have them- skip to #2. They are responsible for stopping the downward travel of the door if the beam (generated between the eyes) is broken, sending it back up to the top. In case a small child or pet tries to go out while the door coming down.
- Symptom of the safety eyes not working or misaligned: the remote will not close the door AND the wall station will not close the door UNLESS you hold down the button until it closes all the way.
- First, make sure nothing is blocking the beam (boxes, shovels, etc.) Then, check to see if the small LED lights are lit on each of the safety eye housings (the little boxes). If one is lit, but the other is not- bend the safety eye bracket (which attaches the eye to the wall or track) of the eye that is not lit around until it 'sees' the other side, and the LED comes back on. If neither light is on, check the wiring out of the case- sometimes the wires get clipped. NOTE: I recommend NOT storing anything near the safety eyes because they are fragile and easily blocked.
- Another common mistake made by homeowners, with some opener brands, is the multifunction wall-station. Some manufacturers include a wall station that has a locking feature, or vacation mode, which will lock-out the remotes and outside keypad. Some will even render the wall station useless as well. The little switch is usually on the top of the wall-button, but the location varies per manufacturer. Check out the owner's manual or usually you can find them online. If it accidentally gets 'locked' it will seem like the opener is dead. A good thing to check before calling a repair technician.
- Garage Door disconnected from opener: this happens more often than you would think! If someone has pulled the red-handled emergency release cord and disconnected the door from the opener, the motor will just run the 'trolley' back and forth- but the door is not attached. This may cause you to think the opener is malfunctioning and call a technician. So check it first- while the motor is running look for the 'trolley', which is the part that is attached to the chain (or belt) and connects to the 'j-arm', which connects to the door itself. If the trolley is moving back and forth, simply wait for it to stop running and then manually move the door until it locks back on to the 'trolley'. Then test the opener and see if it runs the door. If you have a screw-drive, look up from directly under the opener rail and see if the screw is spinning. If so, follow the red cord up to the switch it hangs from and move that switch up until it locks onto the screw, and test opener. If you still cannot figure it out, and if the manual doesn't help- THEN call a technician!
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