craftsman garage door opener
I have a 1/2hp craftsman opener (139.53647SRT1 built June 1996). When attempting to close the door, it stops ~6" from the floor, goes back up and the lights blink. I've done the following:
Checked the sensors--the green lights are on both the gun and receiver.
relubricated the door and tracks.
increased downward pressure (door stops between half way down and 6" from floor...returned to original setting).