Expert Garage Door Sensor Repair Malibu A garage door sensor is a crucial part of the entire system. It is designed to keep the door from closing on cars, people, pets and other objects that may be in the way. The sensors can be found on either side of the door, a little above the floor. Once the door is activated, the sensors let off a low-beam voltage which completes the electrical circuit. When the sensor fails to work the way it…