DIAGNOSIS Your safety sensors are misaligned or obstructed. The blinking light and beeping is the opener's standard alert that it can't see a clear path.
FIX Check the alignment of the two small plastic sensor units on either side of the garage door track, near the floor.
1. Look at the LED on each sensor. One should have a steady green light, the other a steady amber light.
2. If either is blinking or off, something is blocking the beam (a broom, box, or cobweb). Clear it.
3. If clear, gently adjust the bracket of the blinking/off sensor until both lights are solid.
IF THAT DIDN'T WORK The sensor wiring might be damaged. Inspect the thin white wires running from the sensors back to the motor unit for pinches, cuts, or loose connections at the terminals (marked 1 and 2 on the back of the opener).
HEADS UP Never bypass the sensors to force the door closed. The opener will not operate with the sensors disconnected—it's a critical safety feature to prevent closing on a person or pet.