Falcon door operation is affected by proximity sensor. If you, or anyone, is standing
where the sensor -thinks- they are in the way (or anything else) it will not open. I've
had mine refuse to open because the sensor (on the vertical between the doors) was
dirty. Finally, sometimes the sensor is only slightly dirty but the sun is hitting it and
it can't tell if the area is clear ... so it takes the safe path and doesn't open. Even just
rain on the sensor can affect it (not often but I have seen it). - Jim in the PNW