Air fryer will not start; display shows E1 shortly after power-on or when trying to begin a cooking cycle.

Safety first: Unplug the air fryer from the mains and let it cool completely before opening any covers. Do not work on a hot appliance.

Step-by-step checks:

• Power reset: Unplug the unit for 5–10 minutes, then plug back in and try again. Sometimes the control board will clear a transient sensor error.
• Inspect sensor wiring: Remove the top or rear cover (depending on model) to access the heater assembly. Locate the small wired probe (NTC sensor) clipped near the heating element or air outlet. Check for broken, pinched, or burned wires and reseat the connector on the main PCB.
• Check sensor resistance: With a multimeter set to kΩ, measure resistance across the NTC sensor leads at room temperature. Typical Philips NTCs read between 50kΩ–100kΩ at ~25°C (exact value varies by model). An infinite reading indicates an open sensor that must be replaced.
• Inspect PCB connector: Check the NTC connector on the main control board for corrosion, bent pins, or cracked solder joints. Reseat the plug firmly.
• Replace faulty parts: If the sensor is open or physically damaged, replace the NTC temperature sensor / sensor harness specific to your Philips model. If the sensor tests good but E1 persists, the main control board may have a failed sensor input and should be replaced by a qualified technician.

Warning: Do not bypass or short the temperature sensor; this can cause overheating and fire risk.