Garage door opener will not close from remote; opener lights flash twice and door reverses or will not move.

Safety first: Unplug the opener before working on low-voltage wiring. Use a step ladder rated for your weight and place it on a stable surface.

• Inspect wire runs: Trace the two-conductor wires from each safety sensor back to the opener. Look for crushed insulation where staples were used, chew marks from rodents, or pinched sections at the track brackets.
• Check terminal block: Remove the opener light cover. At the logic board, locate the sensor terminals (usually marked SENSORS or with icons). Confirm each pair of wires is fully inserted and the screws are snug.
• Test continuity: If you have a multimeter, disconnect the sensor wires at the opener and check continuity of each conductor from opener end to sensor end. Replace any cable that shows open or intermittent readings.
• Correct wiring: Ensure the white wires from both sensors go to the common terminal and the colored wires go to the sensor terminal. Reversed or crossed wires can trigger a 2-flash error.
• Replace damaged cable: If insulation is damaged or conductors are exposed, cut out the bad section and splice in new low-voltage garage door wire using weather-resistant wire nuts or replace the entire run.
• Restore power and test: Plug the opener back in and try closing the door. If the 2-flash error persists after wiring is verified, the logic board sensor circuit may be faulty and require replacement.