Wine cooler displays E1 and will not cool properly; interior temperature rises above setpoint.

Safety first: Unplug the Gaggenau wine cooler or switch off the dedicated circuit breaker before removing any panels. Work with dry hands and avoid touching live terminals.

Step-by-step checks:

• 1. Power reset: Disconnect power for 5–10 minutes, then restore power. If E1 returns after a few minutes of operation, continue with diagnostics.
• 2. Locate the cabinet NTC sensor: On most Gaggenau wine coolers, the cabinet temperature sensor is mounted behind an interior side wall cover or behind the rear liner, usually near the middle of the compartment. Remove interior shelves and trim as needed.
• 3. Inspect wiring and connector: Check the sensor harness from the sensor to the main control board (often located at the top or rear). Look for pinched, cut, or chewed wires and loose or corroded connectors. Reseat the connector firmly.
• 4. Test sensor resistance: With power still disconnected, unplug the sensor from the control board and measure resistance with a multimeter. Compare to Gaggenau service specs (typically an NTC will read several kΩ at room temperature). An open circuit or 0 Ω indicates a bad sensor.
• 5. Replace the NTC sensor if faulty: Remove the old sensor (often clipped or lightly glued in place). Route the new sensor harness along the original path, avoiding sharp edges and moving parts. Reconnect to the control board.
• 6. Evaluate the control board: If the sensor tests good and wiring is intact but E1 persists, the main control board’s sensor input may be defective. Inspect for burnt components or corrosion. Replacement of the control module is typically required.
• 7. Reassemble and test: Reinstall all covers and shelves, restore power, and monitor temperature and display for at least 30–60 minutes.

When to call a technician: If you are not comfortable using a multimeter or accessing the control board, or if the control module appears damaged, contact an authorized Gaggenau service technician.