Two types of accidental obstructions can cause the safety sensor to prevent a garage door from closing.
Sensor problems on garage door.
First you should check the safety sensors.
Sensor path make sure nothing is obstructing the sensor beam in general garage door sensors block the door from.
This video takes you from my problem description to a successful repair all for under 24 00 u s.
Doityourself has a wonderful explanation.
When the device detects any person or object in the path of a closing garage door it signals the motor to stop the downward action and switch the motion into reverse to stop the obstacle being crushed.
Stand a stepladder at the area of the garage door opener unit.
If your garage door reverses anytime you open or close it there could be a problem with your safety sensor incorrect force settings or there is an obstruction on the doorway.
The transmitters remotes will not work to close the garage door.
Then look to see if the rollers are in working order.
If you do not see a solid illumination or your garage door is not working the problem is most likely due to the sensors being out of line.
If your garage door faces south and the door will not go down.
Knowing how a garage door sensor works allows a homeowner to be watchful for what might affect it.
Sensor power reconnect the sensor to its power supply a common cause of a malfunctioning garage door sensor is.
They need to have a clear line of sight between them in order for the door to work properly.
How a garage door sensor works.
My liftmaster garage door stopped closing the normal way.
Inspect the double strand insulated.
It may be that your safety sensor is being blinded by the light of the sun.
Safety sensor issue to prevent the garage door from injuring someone in the door or damaging an item in the way of the door all models of liftmaster garage door openers come installed with a safety sensor.
Verify if there isn t a block between them.
Unplug the power cord from the outlet at the ceiling.
You will find that the door will only move an inch or so in the close direction and reverse.
Safety sensors are the electronic eyes near the base of the door track on both sides.
The problem is either due to a blocked path between the sensors dirty eyes loose wires at the sensors or at the motor head or just bad sensors.
The garage door sensor yellow light and the green light together create a solid illumination.