Listed below are three common causes of problems experienced with sensors:
Misalignment: If your overhead garage door isn't working properly, it's possible your sensor is misaligned. Most modern garage door sensors are light-based, and they will often light up on the receiver side if the signal is being properly received. If the receiver side isn't illuminating, contact a technician to have the garage door sensor properly aligned. garage door sensor
Filthy Optics: