In this video

After reassembling and mounting the opener, it's crucial to adjust the travel limits to ensure the door opens and closes correctly without over-extending or straining the motor. First, activate the opener to cycle it up and down without the garage door attached (keep the emergency release tripped). Observe where the trolley stops at the 'open' and 'closed' positions. If the travel is too far or not far enough, adjust the limit screws on the side of the opener. Each screw controls a different limit (e.g., 'up' travel, 'down' travel). Turn the screw in quarter-turn increments, testing the travel after each adjustment. On the presenter's opener, a diagram indicates that turning counter-clockwise for the 'down' screw increases downward travel. Adjust until the trolley stops just shy of where it would normally connect to the door's bracket.