Question about liftmaster Chamberlain Garage Door Opener Transmitter 300MC

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The door wont close.

It open fine but when I truy and close it it react as though somthing is blocking it. It stop and beggin to blink. I have to hold the button until it close.

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Assuming you have an electric eye across the door, one side may have gotten moved so that they no longer 'see' each other. There is usually an indicator light on on side that will light up (usually red or green) when the eyes 'see' each other. If they are not 'seeing' each other then they make you go into override mode which requires the button to be held down.

Try re-aligning and see if that helps

Posted on Feb 09, 2009


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