Turn off power to the garage door opener
Inspect both sensors for dirt, damage, or loose brackets
Loosen the mounting screws on both sensor brackets
Position both sensors at the same height
Aim the sensors directly at each other
Adjust the sensors until both indicator lights are steady
Tighten the mounting screws without shifting the sensors
Check that the sensor lenses are clean and unobstructed
Restore power to the opener
Test the garage door by closing it
Re-adjust if the door reverses or the sensor lights blink