If it falls to the floor you may have a broken balance spring on the door frame.
My garage door slides down after opening.
Sometimes the door will open all the way up after it slides back and the light will turn off.
Slipping down a few inches after opening posted.
There are two different types of spring systems for garage doors.
Once the door is up all the way it s resting on the horizontal parts of the track and the resistance of the motor to turning because it is low geared should prevent it coming back down.
It depends on the particular door but if you have a two car garage with on wide door getting 7 years out of a set of springs is pretty good.
Second because of the weak springs the clutch brake in the opener may be.
Once it slides down does it go back up and stop in the correct place if it doesn t maybe the gear or gear shaft on the motor is stripped.
Probably due for a spring failure.
If your garage door slips down below the header after you have opened it you garage door springs need to be adjusted.
Took cover off and gears appear to be fine.
They need to be set to open the door fully without the opener.
Torsion springs are mounted directly above the door and need to be wound with special tools.
No pieces of plastic to show wear and tear.
On 5 10 16 at 1 33 pm to sicboy.
First is your door springs are in need of adjustment.