Air fryer beeps and shows E4, will not start a cooking cycle.

Safety first: Unplug the air fryer before any inspection. Do not open the unit while it is connected to mains.

Steps:

• 1. Verify mains supply: If possible, test the outlet with another appliance or a multimeter. Ensure you are using the correct voltage (e.g., 220–240 V for EU/UK Daewoo models). Avoid using unstable generators or long, undersized extension cords.
• 2. Try a different outlet: Plug the air fryer directly into a known-good wall outlet without adapters or extension leads.
• 3. Inspect power cord: Check the Daewoo power cord for cuts, kinks, or burn marks. Replace the cord set if damaged.
• 4. Internal inspection (advanced): Remove the rear or bottom cover to access the terminal block and PCB. Check that all screw terminals are tight and that there are no signs of arcing or burning.
• 5. Check surge components: On the PCB, look for a metal oxide varistor (MOV) or surge suppressor near the mains input. If it is cracked, charred, or exploded, the board must be repaired or replaced.

Note: Overvoltage protection faults often indicate issues outside the appliance. If E4 appears only in one location or outlet, have an electrician check the supply. If it appears everywhere, the control PCB likely needs replacement.