What to do when the garage door will not close.

Posted 1/22/2013

New style LiftMaster safety sensorThe single one problem I see most and we all have had at some point, no matter what brand of garage door opener you have.

Problems with the safety sensor, photo eyes, The Protector System, Safe-T-Beam and other names. So before you call the repair company check the safety sensor is aligned correctly and nothing blocking the sensor. The opener will not move in the down direction if the safety sensor is not installed.

The safety sensor is the small box “eye” on each side of the door opening and installed correct about 6 inch above the floor. Each one has a little lens facing one another, one is the sending sensor and the other is the receiving sensor. The sending sensor transmits an invisible light beam to the receiving sensor. If an obstruction breaks the light beam while the door is closing, the door will stop and reverse to full open. Also if anything in the path of the light beam or the sensor not properly aligned the door will not close.

Genie safety sensorMost receiving sensor has a light that will come on and stay on as long the beam is not broken. Some has a light in the sending eye to indicate power to the sensor. When you install a new opener, pay close attention to the wires for the safety sensor. Some you can cross wire, when others have to be the same and have designated post for the wires. The safety sensor has to be installed and connected correct for the garage door opener to work properly. I know some will say “Oh, I don’t have any safety sensor on my door”. That can be 2 things, your opener is manufactured before 1993 or whoever installed the opener cheated and did’t install the safety sensor correct.

Marantec safety sensorMost Genie and Overhead opener has a solid green light in the sending sensor and a red light in the receiving sensor.  If it’s an older opener, no light in the sending sensor. When interrupted the red light will be blinking. LiftMaster, Chamberlain and Craftsman opener has green-green light or green-orange light with the orange in the sending sensor. With green-green sensor it’s printed on the end of the sensor who is who. On both type the green light in the receiving sensor will go out when interrupted.

Linear safety sensorWhen you are having problems with the sensor, first of make sure that the sensors are aligned correctly and nothing blocking the path of the sensor. I have seen old insulation, pull down handle and pull down rope be in the way and make the door go back up. The sensor bracket is mounted solid and not moving around. That is whatever it’s mounted on the track or into the wall. Also when mounted on the track, the track bracket has to be mounted into solid wood or the track can move as you close the door. When it’s all solid mounted, point the sensor straight with the door and in level. Some you have to twist the bracket and others sit with a wingnut you can loosen up and adjust the eye and tightened the wingnut.

Old style LiftMaster safety sensorCheck the wires especial if they are spliced into the house pre wiring at the sensor and at the motor head. Also if stapled to the wall, check that none of the staples have not cut any wires (that can happen when install a new opener).

OK, now we have done all we can and it still don’t work. The last chance is a trade secret, check and check again that nothing is in the way of the path of the door. Now press and hold the push button on the wall till the door go all the way down and stop. By doing this you overwrite the system to close the door, but you still have a problem you need to have taking care of.




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