Try making small adjustments.
Garage door opener goes down but not up.
Go along with your safety reversing sensors.
Now it may be the lower limit switch itself but it s more likely to be a relay or ic problem.
When the logic board wears out it can cause your garage door to close then open and vice versa without explanation.
Your garage door s logic board is the brain of your garage door opener.
Adjust the limits as needed.
This will cause the trolley to move into position and reconnect to the garage door.
If your garage door hits it bounces up and starts to open again your garage door is working well.
Check if the limits are properly set.
If the door goes up but you can t make it go down you probably need to adjust the sensors.
T his is a pretty uncommon problem but one that can happen after you ve first installed your garage door opener.
This is almost certainly an electronics problem.
This is related to the up limit switch.
Now press the remote control.
Try opening the garage door with the remote and see what happens.
To fix this issue increase the down limit one quarter turn.
You ll then want to test it again and if it s not right keep adjusting the down limit nob until your garage door hit the board and bounces back up.
However if your garage door doesn t bounce back up then you know you have a problem.
Connect the white wire from the sensor to the white terminal of the garage door opener and then the black and white wire to the grey terminal.
If it is a new installation check the postion of the door arm.
To reconnect the garage door to your liftmaster garage door opener manually close the garage door pull the emergency release handle down.
If the door then goes down when you press the button hit the button again before the door hits the ground and see if it goes up.
It s important to get this switch at just the right distance from the motor so that the door is able to close all the way but the motor also knows to stop running.
Now point the safety sensors at each.
Two things stop the lower direction travel of an overhead door.
There is a latch in the circuit that keeps the down motor on until the lower limit switch is tripped.
Other things could be wrong but they are in the weird category.
Make sure only the safe t beams that came with this garage door opener are installed.
Garage door starts down then stops and goes back up or safe t beam system malfunction.
This brain can wear out in time so you could need a replacement.
Disconnect the pre wire from the garage door opener.
Now put a step ladder under your garage door opener and climb it.
They both have lights and both lights should be on.
