The sending eye on one of my garage doors doesn't light up. The receiving eye does stay lit however. I checked the wiring and nothing is bad... so it seems anyway. I don't understand why the receiving light is on but not the sending eye light. Of course the door will not go down. I also tried holding in the button on the wall to make the door go down to no avail. Does this make any sense. Normally if the eyes weren't alighned the sending light would be on not the receiving light.. someone help... thanks chris

Visually inspect wire from sender to operator(every inch). Or unit may be bad.
If sender is not working, receiving will think path is blocked and will refuse to let you close, some will allow you to hold button down to close, may need to turn of power once closed. You should have a release that you could pull to allow door to close manually.