Sommer opener refuses to close the door, beeps or flashes, and displays E3; door will open normally.

Safety: Do not bypass or tape over safety sensors. They are required for safe operation.

• 1. Check sensor LEDs: Each Sommer photo eye should have an indicator LED. Confirm both are lit solid when the door is clear. A blinking or off LED indicates misalignment or wiring issues.
• 2. Clean the lenses: Wipe both sensors with a soft cloth to remove dust, spider webs, or moisture.
• 3. Align the sensors: Loosen the wing nuts and gently rotate each sensor until both LEDs are solid. Tighten the nuts while holding alignment.
• 4. Inspect wiring: Follow the low‑voltage wires from the sensors back to the Sommer head. Look for staples through the wire, cuts, or corrosion at the terminals. Re‑strip and re‑terminate wires if needed, matching polarity as indicated on the opener.
• 5. Test operation: Try closing the door with the wall button. If it only closes when you hold the button down, the sensor circuit is still not satisfied.
• 6. Replace faulty sensor: If one LED will not light even with good wiring, replace the defective Sommer photo eye pair as a set.