Display shows dF or DEF, and the compressor cycles differently than usual.

Safety first: No immediate disassembly is required. Do not bypass safety devices.

• Wait for cycle to complete: If dF appears briefly and then clears within 20–40 minutes, this is likely a normal automatic defrost cycle.
• Check temperature: Use a thermometer to ensure the freezer returns to its normal operating temperature after the defrost period.
• Persistent dF: If dF remains on the display for several hours and the compressor does not restart, unplug the unit for 5 minutes, then plug it back in. If the compressor still does not run, test the defrost sensor and heater circuit as you would for a defrost fault.
• Board replacement: If the control remains stuck in defrost with a good heater and sensor, the main control PCB defrost relay may be stuck and require replacement.