Garage door won’t close? Important Information On Garage Door Safety Sensors.

The safety sensors are an integral part of your automatic garage door opener. When you click on your garage door opener and the door doesn’t fully open or shut, chances are it’s because the garage door safety sensor has detected on an object or person in it’s path. This is essential for preventing damage to the door, the opener, and to the object or person in the way of the door. Unfortunately, no matter how well these garage door sensors are designed there will from time to time be problems or failures, and it can be very frustrating if you cannot close your door.

Safety sensors are located in the bottom corners of your door, usually attached to the rail. On one side there will be a sending unit, and on the opposite side a receiver. They communicate using infrared light. The sending unit works like a flashlight, and the receiving sensor works like an electronic eyeball. Together they create an invisible (to humans) and intangible (you can’t touch or feel it) trip wire that will tell the motor to stop if there is an obstruction. If this happens, the door will reverse and the main lights will flash on and off several times as a warning that something is in the path of the door. The door can open, but will not close as long as there is something blocking the sensors from “seeing” each other.

By far the most common problem is loose storage, or nearby items blocking the sensor. Almost everyone has some items beside the tracks, in the corner of the garage. You know the usual culprits – shovels, brooms, hockey sticks, maybe your bike tire. All these common items can block a sensor and even though they may not be in the way of the door closing, it will still stop the door if the receiving sensor can’t see the sending unit. Fixing this is simple: keep all items at least 6 inches away from the garage door.

The next issue to look for is a misalignment of the garage door safety sensors. Simply put, this means the two sensors are not aimed at each other correctly. This happens more easily than you might think. If you have a garbage bin near the door you might accidentally hit a sensor with it when taking out the trash. If your garage is small or crowded, it’s easy to accidentally kick or knock one of the sensors when walking by. Sometimes a child or a family pet will play with a sensor or otherwise move it. Sometimes they just get loose over time and gravity pulls them down. Regardless of the reason they moved, you will need to ensure the sensors are aimed directly at each other. Each sensor has a small LED light. The sending unit will always be lit, but the receiving sensor will only be lit if it can see the sending unit. So if you see one light on and one is off, you have a problem! Simply loosen the sensor, and aim it as best you can. It should be parallel to the ground, and pointed strait at the sensor on the other side of the door. Make sure that once you have it aimed well you tighten it. You don’t want to have to realign it all over again!
Another simple thing to keep in mind is spider webs. They usually won’t be able to block the sensor, but garbage or leaves blowing around can get caught in the webs, and they will block your sensor! Always keep the bottom weather seal, the floor and the tracks clear of dirt, foliage and cobwebs.

One more thing to note is that like most electronics, water is not good for them. If you have water leaks, or you wash your car near the garage with the door open, be sure to keep the hose pointed the other way! In the same line of thinking, if your sensors seem to be aligned and nothing is in the way, inspect the wires going to the sensors. In some cases the wires can become corroded and this can cause them to malfunction too.

What’s that you say? Oh, you don’t have kids or pets and you don’t want to bother with those pesky safety sensors. Want to know how to bypass them? DON’T! Even if you’re not worried about safety, you should keep in mind that bypassing them can void a warranty. Both on the motor and the door. Also you should know that the safety sensors are not part of a simple NO or NC circuit, so you cannot bypass them with a jumper wire or resistor. In conclusion, simple housekeeping and a little common sense will keep your safety sensors and the rest of your garage in good shape for many years.