LiftMaster opener will not close from remote; UP arrow LED blinks four times repeatedly.

Safety: Do not tape over or bypass sensors.

• Tighten brackets: Ensure both sensor brackets are firmly attached to the track or wall and do not move when the door operates.
• Fine-tune alignment: Even if LEDs are on, slightly adjust the sensors until the receiving sensor LED is brightest and most stable.
• Shield from sunlight: If direct sunlight hits the sensors, install small shades or reposition slightly to reduce interference.
• Secure wiring: Tighten all terminal screws at the opener and ensure wire nuts or splices are solid.
• Test multiple cycles: Run the door several times to confirm the error does not recur.