What exactly do garage sensors do?

Garage door sensors help to detect if something is underneath your garage door. There’s a few types of garage sensors available, the main one being a photo eye (or safety eye) sensor – which are made of two small components that appear like cameras, placed on opposite sides of the garage door frame, usually between to and six inches above the floor. When the photo eye sensor is activated, a photoelectric beam is sent across the door opening. If anything blocks this beam, like an obstruction in the door opening, the sensor will prevent the garage door from closing, if the door is closing while the sensor detects an object, the door will reverse directions and open. If photo safety eyes become misaligned, they won’t function, as they cannot create a beam, causing it to think something is blocking the door.

Determining Garage Door Sensor Misalignment

1. Visually inspect the garage to determine if sensor eyes are misaligned and manually close the garage door. Look at the light on one of the photo eyes – it is working and aligned when it has a solid yellow or green light – then check if the other photo eye has the same color. If either photo eye has a flashing light, there is a misalignment.
2. Manually Adjust the sensors to correct the misalignment. Measure the height of each sensor from the ground to make sure that they are the same, and adjusting them to make them equidistant – use a level tool if you need it. Sensors can sometimes become misaligned when loose – and a sensor is loose if it wiggles back and forth. Look for a nut or screw that you can manually tighten after the photo eye is realigned. Then a test to see the issue is fixed using the garage remote.
3. Your garage door sensors could be broken due to a range of issues. This will cause them to malfunction or refuse to work even when properly aligned. First, try to wipe the sensor clean with a clean microfiber cloth. It’s possible that UV rays from the sun have damaged the sensor due to its infrared light. Try to reposition photo sensors so that the transmitting sensor is on the side of the door that does not experience direct sunlight. You might also want to install a sun shield in front of the sensor to block out the sun’s rays while not blocking the sensor beam. If the sun has been hitting the sensors for a long time, you might need to replace them. 

Additionally, power issues can be impacting your garage photo eye sensors. If there is no light on both or either of the sensors, check the power supply, try to plug in and unplug the sensor or check your circuit breaker to make sure the circuit has not tripped. Sometimes loose or torn wires can disrupt the power on your sensor – this usually indicates its best to fully replace the garage door sensor.