Question about liftmaster Chamberlain Garage Door Opener Transmitter 300MC

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Garage wont open competely

When door is attached it will not open. will work properly when door is not attached

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There is a trip lever along the garage door track.
When door goes up, it trips the lever and turns off the opener.
The trip lever is adjustable. Loosen it and move back 1" or so.
If that is not far enough, move it back 1/2" more.

Posted on Apr 20, 2013


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