Display shows dO or Door Open and alarm sounds even when the door appears closed.

Safety first: Unplug the freezer before removing the door switch or working with wiring.

• Check door alignment: Ensure the door closes squarely and fully. Adjust hinges if the door is sagging and not pressing the switch.
• Locate door switch: The door switch is usually in the door frame. Press it by hand; the interior light should turn off and the alarm should stop.
• Test switch: Remove the switch from the liner, disconnect wires, and test for continuity with a multimeter while pressing and releasing the plunger. Replace if it does not change state.
• Inspect wiring: Check for broken or loose wires at the switch and where they enter the cabinet.
• Control board: If a new switch does not clear the code, the electronic control board may be misreading the input.