Craftsman 1/2 HP GDO - Partially Opening
My 1995 Craftsman 1/2 HP garage door opener, Part No. 41A4315-6C starts to open the door, but then it immediately reverses. Doesn't matter if I am using my car remote(s), the outside keypad or the inside switch. When it occurs, the light flashes on and off and there is a clicking from the power unit for about 5 seconds. The door will shut if I hold the button inside the garage down, and it will open normally after that from any of the remotes. It only has a problem when trying to shut it. The sensors (that stop it from closing if blocked)are clear and seem fine. The rollers all appear in proper place, and are lubricated fine. What am I missing?