When you say sensors, are you talking about the photo-eye that checks if obstruction is in path of garage door?
1)
You can buy sensors for $20-30. They seem generic
2) The new openers may be set up so by-pass is not an option.
Solution: In that
case, you can move sensors above the garage door and put them face
to face to see if that helps.
3)
The way the sensors work is this. One side produces beam of light. Other side receives light. The receiver keeps a circuit closed at all times when light is received. If no light, then the circuit opens up and an electronic part interprets the lack of signal and turns off opener.
Solution: one side produces light. It does not have a switch. The other side has the switch. You can disconnect (or cut) a wire see which side has the light. The other side has the switch ... cut the 2 wires on the side with a switch, cap them off, and then see if opener works. Next twist the 2 wires together and see if opener works.
4)
Fall-back position: Mark your wires and you can put it back the way it was.
