I have a liftmaster formula 1 whisper drive garage
door opener that when I try to close it it locks,
but if I keep the button press it work it closes.
But to open it there is no problem. It has one beam light on each side of the garage so if something is in the way it's stop's those little
beam light's have a green light on the side. One of the light only has a green light I switched the green light's and only one is working. I also
completly disconnected them from the motor and checked the track's where the wheels go and they go freely? THANK YOU VERY MUCH FOR YOUR HELP