If a garage door comes down on a child or pet, the door can do some damage, so to protect your children and pets, garage door manufacturers will use obstruction sensors to prevent the door from closing when someone or something gets in the way. Normally, these sensors work just fine, but when they malfunction, it is important to know what steps to take to get them working again.
Normal Sensor Operation
The sensors on a garage door have two main components: an electronic eye and a laser. These should be installed so that the laser and the eye line up. As long as the laser is detected by the eye, the door will function as normal, but when something blocks the laser, the sensors send a signal to the garage door motor, which prevents the door from closing.
Sensors are installed low to the ground so that they can detect small children and pets as well as anything that extends up from the ground to a greater height. While the position close to the ground is important for detecting obstructions, it also means that the sensors can easily get bumped by other passing children, pets, snowblowers, etc. When a sensor gets bumped, it can get out of alignment, which means the laser won't connect with the eye like it should, and the sensors will send a false signal to the garage door motor. Thus, your door won't close even if there is nothing in the way.
To get your sensor working again, you should be able to gently maneuver your sensor until they line up again. Many sensors will be equipped with an indicator light, which will glow red when the sensors are out of alignment, but will grow green when they are in alignment. By slowly moving your sensor left and right, up and down, you should be able to get it into position to turn the indicator light green. Once you sensor is in the right place, your problem is solved.
Not every problem with obstruction sensors can be solved simply by realigning your sensors. You might also have an electrical short or a badly damaged sensor. When it comes to electrical problems or replacing your sensors, your best bet is to call in a professional from a company like Girard's Garage Door Services to make repairs for you. Obstruction sensors are a small component that can make a big difference in the function of your garage door.