Freezer interior temperature fluctuates widely; some days food is very hard, other days slightly soft, without user changes.

Safety first: Unplug the freezer before accessing controls or wiring.

Step-by-step checks:

• 1. Monitor with thermometer: Place a freezer thermometer inside and log temperatures over several days to confirm fluctuations.
• 2. Inspect sensor connections: Access the cabinet NTC sensor and ensure its connector is tight and free of corrosion.
• 3. Mechanical thermostat models: If equipped, gently tap the thermostat housing while running; if the compressor cuts in and out erratically, replace the thermostat.
• 4. PCB inspection: Check the main PCB for loose connectors or signs of heat damage.

When to call a technician: Intermittent faults can be difficult to diagnose; a technician with access to service data and test equipment may be required.