Question:
I'm having trouble with a 9 year-old Overhead Door Legacy
garage door.
The sensors work fine when the door is within 2' of closed,
but they both lose power (both lights, green on one sensor,
red on other, go out, and the sensor voltage at the motor
unit goes to zero) as the door opens. Sometimes they come
back on as the door nears 4' of closed, always back on
within a foot or two.
Symptoms lead me to believe I have a lose connection
somewhere, but I don't know much about garage door
openers. Anyone know how the short would be related to
the garage door's position?
Answer:
I would guess that it must be something in the control unit. Thinking
of a poor solder joint on a circuit board. But that would not explain
why it would lose power relative to the position of the door. Still, if
you open the unit it would be worth while to go over the joints with a
solder iron. Sometimes the joint looks fine until you look at it with a
microscope.
I assume you are talking about sensors to open the door if it shuts on
an object (like you). Sensors may be disabled at the very end so they
don't reverse the door as it hits the actual floor. The disabling
switch, or mechanics that operate it, may be the problem.