Don t fault their hesitation there are several reasons for this frustrating behavior.
Garage door moves back and forth.
Sometimes garage doors close half way change their mind and go back up.
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Garage doors come with a reverse mechanism which serves as a safety feature.
If that doesn t fix the problem take a look at the auto reverse function.
I installed 2 of these jan 2015 and they have been doing.
Run the garage door opener to move the trolley back and forth along the garage door opener rail to check for binding.
Disengage the door from the trolley by pulling the emergency cord if none of the basic checks reveals a simple explanation for why the door won t open.
Replace the rail or trolley if damaged.
Open and close the door manually checking for smooth door operation.
I think the problem is the outer carriage and inner carriage have so much clearance they rock back and forth.
The door will move back and forth sometime 1 2 inch sometimes 1 foot.
They seem to either love teasing you or fear closing.
Oddly enough it seems to follow a sequence every 3rd push of button it seems ot move the most about 1 foot the green led blinks 4 times.
It may need adjustment in order to function properly.
Causing the loud rattling.
Have a garage door repair technician fix the door and tracks if the door binds up on the tracks.