Air fryer beeps and shows E4; cooking cycle will not start or stops immediately.

Safety first: Unplug the unit. Do not attempt to run the fryer again until the fault is identified; a shorted heater can be a fire risk.

• Step 1 – Visual inspection of heater: Remove the basket and look at the heating element. Check for broken coils, heavy carbonization, or metal parts touching the element that could cause a short.
• Step 2 – Access heater terminals: Remove the outer housing to reach the heater terminals and wiring. Inspect for burnt connectors, melted insulation, or signs of arcing.
• Step 3 – Test heater resistance: Disconnect the heater wires from the PCB. Measure resistance across the heater terminals. Compare to the service manual or typical values (often 10–40 Ω depending on wattage). A reading near 0 Ω or visible short to chassis indicates a failed element.
• Step 4 – Check for short to ground: With one meter lead on a heater terminal and the other on the metal chassis, verify there is no continuity. Any continuity suggests the element is shorted to ground and must be replaced.
• Step 5 – Inspect PCB: Examine the main control board for burnt tracks, cracked solder joints at the heater relay, or damaged components. Replace the PCB if there is visible damage or if E4 persists after replacing the heater.
• Warning: Do not bypass fuses or relays. Always replace with genuine Moulinex-rated parts.