Why Is My Garage Door Sensor Blinking Red

Garage doors are a source of convenience and security in our daily lives, just with a push of a button or a quick combination on a keypad. But when they start to malfunction, things can take a very frustrating turn.

The most common issues in garage doors usually involve improper opening or closing. These malfunctions often suggest a problem with the safety sensors. A frequently asked question in this department is: why is my garage door sensor blinking red?

garage door sensor blinking red

When the infrared sensors aren’t working properly, chances are one of the sensor lights will start blinking. The problem could be due to a blocked path between the sensors, dirty photo eyes, loose wires at the sensors or the motor, or simply bad sensors. In any of these cases, the transmitter’s remotes will fail to close the garage door.

Keep reading to find out more about the causes of a blinking red light on a garage door sensor and how you can fix the problem.

How do Garage Door Sensors Work

The first step to pinpointing and fixing an issue with your garage door sensor is to understand how this sensor works.

Since the early 1990s, automatic garage doors in residential areas have featured safety sensors to prevent the door from closing on a person or an object. Similarly, your garage door has one of those sensors to tell if something is blocking the door’s way before it closes.

As such, the sensor on your automatic garage door is an essential component to guarantee safety. If it does detect something in the path of the garage door, the sensor will reverse the direction of the closing door and return it to the open position.

So if the sensors on your garage door malfunction or stop working, not only does this cause inconvenience, but it also poses a serious safety hazard.

What it Means When a Garage Door Sensor Blinks Red

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Light indicators on a garage door serve to inform you of the status of the sensors. For example, if your garage door sensors are out of alignment, the exterior LED light may blink red when you try to close the door.

Of course, the color of the light depends on the manufacturer, but it generally goes like this: green lights mean that the sensors are functioning properly, whereas red blinking indicates an issue with the sensors.

If you do see your garage door sensor blinking red, the problem could be one of the following:

  • Obstruction of the sensor’s path — make sure nothing is blocking the sensor’s beam as this will prevent the door from closing, just like when your car is in the doorway.
  • Dirty sensor eyes — give your sensor lenses a good cleaning every now and then to avoid malfunctions. A lot of times, sensor lenses can be covered in dirt without you even realizing it. This happens when you neglect maintenance and don’t clean the sensor eyes for a long period, especially if you live in an area with a lot of wind and pollution or somewhere close to an intersection. All this causes dust and dirt build-up on your sensor’s lenses, preventing them from working properly.
  • Moisture affecting the sensor — sometimes, wetness from rain or your water sprinklers can get in and around the garage door sensors. This is a possible cause of the malfunction, so make sure your sensors are completely dry.
  • Sensor alignment issues — your garage door sensors may be blinking red because they’re misaligned. In this case, you should make sure that both sensors are lined up with each other.
  • Sensor damage — as with any electronic component, wear and tear could take a toll on your garage door sensor. As such, you should check the sensor for damaged wires especially if you’ve been using the same one for longer than ten years.

Troubleshoot a Garage Door Sensor that’s Blinking Red

The following are some basic troubleshooting tips that may help you fix the problem:

  • Check if there are any objects obstructing the doorway and remove them. Give the garage floors a good sweep and carefully inspect the sides to make sure there are no objects blocking the pathway of the sensor’s beam.
  • Give the lenses of your sensor a thorough clean from time to time even if you can’t see evident signs of dust covering them. Use a clean, dry, and lint-free cloth to get the job done.
  • Check the alignment of the sensors. If they’re not properly aligned, make the necessary adjustments to have them facing each other.
  • As we mentioned earlier, moisture in and around the sensors can be the cause of the malfunction. If you do notice wetness, dry the exterior and just allow the interior to dry up for some time before trying to open your garage door.

How to Test a Garage Door Sensor

Now that you understand how garage door sensors work and how to troubleshoot some of the common issues, you may want to test your sensor’s functionality. This can help you determine if your garage door sensor is really faulty and whether or not your troubleshooting worked.

To test your garage door sensor, grab any common object, such as a cardboard box, and put it in the path of the sensors. After that, try to close the garage door.

If the door reverses, your sensor detected the obstruction and is functioning properly. If the door closes on the box, you’ll need to look more into the problem with your sensor.

Conclusion

So why is my garage door sensor blinking red? When the infrared sensors aren’t working properly, chances are one of the sensor lights will start blinking.

The problem could be due to a blocked path between the sensors, dirty photo eyes, loose wires at the sensors or the mote, or simply bad sensors. In any of these cases, the transmitter’s remotes will fail to close the garage door.

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