E9 error code, freezer may show alarm and temperature may rise unexpectedly.

Safety first: Unplug the freezer before working around the door switch or control board.

Steps:

• Locate door sensor: On upright Grundig freezers, the door switch is usually in the cabinet frame near the top or side; on chest freezers, it may be under the lid trim.
• Check magnet alignment: Ensure the magnet in the door aligns correctly with the sensor when the door is closed. Adjust door hinges if necessary.
• Test switch/sensor: Remove the switch or access the sensor. Use a multimeter to check continuity (for mechanical switches) or to verify reed sensor operation by bringing a magnet close and observing continuity change.
• Inspect wiring: Look for broken or pinched wires, especially near hinges.
• Replace faulty parts: Install a new Grundig door switch or door sensor if defective. Reconnect wiring securely.
• Reset and test: Restore power and confirm that the door alarm and E9 error clear when the door is closed.