When the opener reverses the screw turns the opposite way and the nut travels back.
Garage door opener goes down a little then back up.
Here s a rundown of some of the possible reasons this can be happening.
Turn the down limit switch screw clockwise one turn with a flat blade screwdriver if the garage door closes and then begins to open back up.
If these can t see each other when the door is almost shut it will send a signal to the garage door motor to open back up.
If the door hits something hard it will reverse.
This is almost always the result of a dirty or obstructed safety feature.
If the door reverses and the lights blink 10 times there s still a problem with the sensors or something tripped them on the way down.
Check all of you conenctions and the installation of the new logic board.
If it moves all the way up now then the trolley should be okay.
If the door had hit a stop it would not have reversed.
Sometimes the sensors will be in alignment and just as the door gets close to being shut it will vibrate enough to push one sensor off.
Possible reasons why your garage door hits the floor then goes back up as is the case with so many issues at the home there s no one reason why your garage door closes then opens.
A careless or rushed parking job can cause the car s bumper to block the sensor.
There may be two nuts on one track.
Your garage door sensor works by having two photo sensitive devices on either side of the garage door.
By adjusting the starting position of whichever nut the opening and closing limits are set.
See if you can find a manual online and go throught the setup steps again.
The garage door will automatically go in reverse.
One for the opening limit and one for the closing limit.
Try running the opener with the door still disconnected.
In order to fix this you ll want to make small changes to the close limit setting until the door opener knows to stop once the door has reached the floor.
Garage door only travels a little way and then reverses does your garage door only travel a little way 6 inches or so and then reverse.
Your travel down setting needs to be adjusted.
If the door seems okay there may be a problem with the trolley or the opener itself.
If your garage door is closing fully and then reversing to open again then it may be due to a problem with the close limit switch.