Sensors may fall out of alignment over time so it s important to understand how to align garage door sensors.
How to fix garage door sensor alignment.
But if the light on the receiving sensor is blinking you may have problems with garage door sensor alignment.
Higher than that can miss many low lying objects including pets.
Lower is easy to stand above with a foot on either side.
In other words something is probably blocking the beam.
If your garage door sensors are outside of this range remove them entirely from the garage door frame and install leveled inside the safe zone.
This is a brief demonstration on how to adjust the safety sensors on your garage door.
Garage door sensors are designed to prevent the door from closing if something obscures the sensor.