Common Reasons a Garage Door Sensor Stops Working (& How to Fix it)

Garages always need an additional measure to become safe. As door panels are heavy and people always frequent the garage, there’s a chance that accidents can happen. A traversing garage door can cause danger to kids and damage personal belongings. Vehicles may not be in the best position before a traveling panel closes the garage.
In 1993, garage door sensors became mandatory in the United States. It means that for every garage owner who wishes to install new doors, adding sensors is non-negotiable. Sensors save lives and things, and it’s only reasonable to have fully functional sensors all the time.
The issue arises when the sensors malfunction or stop working altogether. The mechanism of the doors in the garage doesn’t have any other auto-reversal detection devices to prevent damage. Let this guide help in finding the common reasons sensors stop working. In addition, we present possible solutions to help recover sensor issues.
Sensors are not properly aligned
Door sensors are always on the foot of the frame tracks. Usually, the installation of garage door mechanisms includes the sensors as well. These devices are around 6 inches from the ground. Both sensors must be precisely on the exact height placement as these devices should detect each other properly.
When the sensors don’t align well, the receiving sensor doesn’t detect the emitted light from the sender. Both sensors wont detect the presence of any item or person along the path. If there are obstructions on the pathway, these sensors won’t be able to signal an auto-reversal. It’s best to know how to adjust garage door sensors to align them again.

Solution: How to align garage door sensors
- Turn off the sensors from the power supply.
- Gather the proper tools for the alignment adjustment. Get a screwdriver, level, and long string.
- Loosen the screw of the sensor on one side and tie the string. Do the same for the other side and tie the other end of the string.
- Modify the placement of the sensors on the tracks slowly by moving the sensors up or down the tracks
- Using the level, ensure that both sensors are at the same distance from the ground. Check the string level from afar and move the sensor as follows.
- Tighten the screw in place and test the sensors again.
Sensors are dirty and not well-Maintained
Simple things can complicate a lot of situations. The same is true for fully functional sensors. Over time, dirt and fine particles will build up in the sensor mechanism. Because it always has outside exposure, it will likely accumulate dirt on its surfaces.
Dirt accumulation and moist photo eyes lead to malfunctioning sensors. When it rains, or there’s too much wind blowing dust around, the dirt and water harden around the sensor. For this reason, it’s much easier to mitigate the issue.
The garage door won't close
One of the signs that signify this problem is that the door panels don’t travel down. The sensor wrongfully detects some obstruction with the photo eyes. Then, the sensor signals the garage door opener not to lower down the door panels.
Solution: Schedule regular garage inspection
It’s always best to schedule a regular inspection around the garage. You don’t only benefit from a clean garage. It’s better to catch issues and solve the damages beforehand if you can. For dirty photo eyes, wipe down the photo-eye lenses and get rid of the dirt. Do this regularly to prevent “fake obstruction detections.”
There are damages to the sensor
Sensor damage often poses the most severe issues to the entire mechanism. Unlike a dirty sensor or a misaligned sensor, damages require professional services for repair. It takes expertise and experience to take apart sensors and figure out the damage. The most obvious sign is garage owners experiencing symptoms and warnings of a malfunctioning sensor.
Sensor wire damage
When there is wire damage in the sensor devices, it will cause problems to the system’s function. Loose wire lengths may be suffering from stress, preventing the sensors from working properly. Also, tangled wires with the opener can cause damage to the sensor in the long run.
Weather conditions play a significant role in wire damage too. Many wires are prone to corrosion. Without proper wire covering or any overheated spots, sensor wires can cause a shortage. Always check the receiving sensor for a constant beam of green light. Damaged sensors send all sorts of wrong signals even without any path presence.
Why are my garage door sensors not lighting up
- Excessive sun exposure prevents the photo beams from detecting the pathway
- Compromises during installation that lead to gradual damage
- Door sensors wear out from old age
- Wire damages in the system (both from opener and sensor)
- Overloaded wires that lead to damage
Solution: Garage door sensor replacement services
No matter what reason there is to replace the sensor, it’s always best to call in experts. There experienced technicians with license and training to help deal with damaged wires or sensor units.
Always invest in the services of experienced professionals who have the expertise and know how to replace garage door sensors. It’s best not to compromise the safety measures inside the garage.
Power issues affect the sensor
The first step is to check the cleanliness and alignment of the sensors. Next is to assess any present damage in the mechanism. If all things check out in these aspects and the sensors still don’t work properly, check the power supply.

Solution: Assess the sensor power supply
Sometimes, home wiring systems can be old and inefficient. As the power supply connects to sensor wires, it directly affects the sensors of the mechanism. Check if both sensor devices in the tracks aren’t flashing a beam of light. Fuses can blow due to drastic changes in the voltage, prompting an automatic shut-off.
Contact a garage door repair company for sensor repairs and inspections
Here at Centrum Garage Door Repair Garage Door Repair, we are a team of highly skilled professionals. We offer our sensor installation and repair for damaged sensor devices. We have the knowledge to handle any model and brand of sensors. Our team is always available to help deal with a safety feature that should be functional all the time.