Galanz freezer displays E4 and may not defrost properly, leading to ice buildup on the evaporator.

Safety: Unplug the freezer. The defrost heater operates at mains voltage; do not test it live. Wear insulated gloves.

• Access the evaporator and heater: Remove interior shelves and the rear panel to expose the evaporator coil. The defrost heater is usually a metal or glass-encased element at the bottom or woven through the coil.
• Inspect for obvious damage: Look for burnt spots, broken heater tubes, or melted wiring. Check the defrost thermostat/thermal fuse (small round or capsule device clipped to the coil) for signs of overheating.
• Test the heater: Disconnect heater leads. Measure resistance with a multimeter. A typical heater will show low resistance (e.g., 20–200 Ω). If it reads open (OL), the heater is bad.
• Test the defrost thermostat/fuse: At freezer temperature, the thermostat should be closed (near 0 Ω). If it is open and never closes when cold, it is defective.
• Replace failed parts: Install a new Galanz defrost heater and/or Galanz defrost thermostat/thermal fuse as needed. Secure them in the original positions and ensure wiring is routed away from sharp fins.
• Check wiring and board: Inspect the harness from the heater area to the main control board for burns or breaks. At the board, reseat the defrost circuit connector. If the heater and thermostat test good but E4 persists, the control board defrost relay may be faulty and the main control board may need replacement.
• Reassemble and monitor: Reinstall the evaporator cover, restore power, and allow 24–48 hours. Check that frost does not build up heavily on the evaporator and that E4 does not reappear.