They both have lights and both lights should be on.
Garage door opener goes down but not up.
Now it may be the lower limit switch itself but it s more likely to be a relay or ic problem.
To reconnect the garage door to your liftmaster garage door opener manually close the garage door pull the emergency release handle down.
Check if the limits are properly set.
There is a latch in the circuit that keeps the down motor on until the lower limit switch is tripped.
This brain can wear out in time so you could need a replacement.
T his is a pretty uncommon problem but one that can happen after you ve first installed your garage door opener.
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.
Adjust the limits as needed.
To fix this issue increase the down limit one quarter turn.
Try making small adjustments.
Go along with your safety reversing sensors.
This is related to the up limit switch.
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.
Garage door starts down then stops and goes back up or safe t beam system malfunction.
However if your garage door doesn t bounce back up then you know you have a problem.
If your garage door hits it bounces up and starts to open again your garage door is working well.
If the door goes up but you can t make it go down you probably need to adjust the sensors.
Your garage door s logic board is the brain of your garage door opener.
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.
If it is a new installation check the postion of the door arm.
Two things stop the lower direction travel of an overhead door.
When the logic board wears out it can cause your garage door to close then open and vice versa without explanation.
Now press the remote control.
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.
This is almost certainly an electronics problem.
Now point the safety sensors at each.
Try opening the garage door with the remote and see what happens.
Check if the safe t beams red led light is flashing.
Disconnect the pre wire from the garage door opener.
There is one on each side of the door.
Get logic board replacement.
Other things could be wrong but they are in the weird category.