The opener can self diagnose any issues.
Garage door opener stops and flash twice.
In both cases your safety eyes will not glow steadily.
To unlock your garage door opener push the lock button for 5 seconds.
It informs you of an issue by flashing the diagnostic led light a certain amount of times.
One is the arrow keys found on the opener and the second is through the small led light located next to the learn button.
At times the garage door opener can malfunction and the garage door will not open or close.
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.
If this doesn t fix your problem then the problem is more than likely the safety reversing sensors.
Counting garage door opener flashing led light door not moving read more.
One flash indicates that your safety sensor wire may be open broken or disconnected if your opener flashes twice then your sensor wire is either shorted or the black and white wires could be reversed.
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.
Press and hold the up button till the garage door is in the fully opened position press the adjustment button to confirm.
The garage door opener light will flash twice and the down button will begin to flash press and hold the down button till the garage door reaches the fully closed position.
The amount of times they flash corresponds to a specific opener issue.
Once you push this button the light on the garage door opener will flash twice.
Liftmaster comes with two methods of self diagnosis.