F18 is displayed and the refrigerator may show a door alarm even when the doors are closed.

Safety: Disconnect power before adjusting door hardware or accessing sensors.

Steps:

• 1. Check door closure: Ensure the door closes fully and the gasket seals all around. Look for items inside blocking closure.
• 2. Inspect hinges: Tighten loose hinge screws and adjust the door height/angle so it aligns properly with the cabinet.
• 3. Test door switch/sensor: See door switch fault steps. Replace the switch or sensor if it does not change state when the door moves.
• 4. Magnet check: For magnetic sensors, verify that the magnet strip in the door gasket is intact and not damaged.
• 5. Control board: If the sensor is working but the alarm persists, the main control board’s door input circuit may be defective.

Note: A persistent door alarm can also indicate a wiring issue in the door harness, especially on models with through-the-door features.