Display shows E15 and the refrigerator may beep continuously or show a door-open warning even when doors are closed.

Safety: Unplug the appliance before adjusting hinges or accessing door sensors.

• Check door closure: Ensure the door closes fully and evenly. Look for items or shelves preventing full closure.
• Inspect door gaskets: Check for twisted, torn, or hardened gaskets that prevent a tight seal. Warm the gasket gently with a hair dryer and reshape if needed.
• Test door switch/sensor: Manually press the door switch or place a magnet near the sensor area and observe if the alarm stops (with power on for testing only). If not, the switch or sensor may be faulty.
• Adjust hinges: If the door is sagging, adjust the top or bottom hinge screws to realign the door so it seals properly.
• Replace faulty sensor or switch: Install a Grundig-compatible door switch or magnetic sensor if it fails continuity tests.
• Reset and test: Restore power and verify that the door alarm behaves correctly and the E15 code clears.

If the door hardware and sensors are good but the alarm persists, the main PCB alarm circuit may be defective and require professional service.