On May 28, 1:52*am, "OMB" No-spam@this-address wrote:
Not sure what they are called, but I'm talking about the little devices low
on the garage door frame that detect when an object such as an animal is
under the door.

One of these got knocked out of alignment when something fell against it.
So now, the garage door won't close unless I hold the button down while it
closes.

I don't know how to align them so they work again. *I have not been
particularly observant as to whether there is supposed to be a light showing
on both of them, or only one. *Right now, there is a light only on one side
of the door frame.

Anyway, I'd appreciate some advice on how to align these devices. *It is a
16 foot opening, so laying a board across from one to the other is pretty
much out.

Bob

The "safety lights" / auto-reverse "electric eyes" that I've dealt
with have been very forgiving with respect to alignment.

I just "eye balled" them into alignment until both indicator lights
came back on.
The methods suggested by others will work...eye balling alignment is
quicker & "good enough".

The GDO systems I've worked on have had a red light on each
unit....system is aligned correctly when light on each unit
illuminates.