Freezer beeps and displays F1, temperature too high and food starting to soften.

Safety first: Unplug the freezer from the mains before removing any panels or touching wiring. Do not work on live circuits.

Step-by-step checks:

• 1. Power reset: Unplug the freezer for 5–10 minutes, then plug back in. If F1 clears and does not return, it may have been a temporary glitch.
• 2. Locate the freezer sensor (NTC): On most IKEA upright and chest freezers (often manufactured by Whirlpool/Electrolux), the freezer temperature sensor is clipped to the evaporator cover or mounted on the rear wall inside the freezer behind a small plastic cover. Remove baskets and inner back panel if needed.
• 3. Inspect wiring: Check the sensor wires for cuts, pinches, or signs of ice damage. Ensure the connector is fully seated at the sensor and where it plugs into the main control board (usually behind the top/front control panel or at the rear under a metal cover).
• 4. Test the sensor: With the appliance unplugged, disconnect the sensor and measure its resistance with a multimeter. At around -18°C, most NTC sensors used in IKEA freezers read between 8–30 kΩ (check service sheet if available). If the reading is open (OL) or shorted (near 0 Ω), the sensor is faulty.
• 5. Replace the sensor if defective: Remove the old NTC from its clip or bracket, route the new sensor along the same path, and secure it away from moving parts or sharp edges. Reconnect to the harness and reassemble panels.
• 6. If sensor tests OK: Inspect the control board for burnt components or corrosion. If wiring and sensor are good but F1 persists, the electronic control board is likely faulty and should be replaced by a qualified technician.

When to call a professional: If you are not comfortable testing resistance or accessing the control board, or if replacing the sensor does not clear the error, contact an authorized IKEA/Whirlpool/Electrolux service center.