Safety first: Unplug the microwave before accessing internal components.

Step 1 – Reset and test: Disconnect power for 10 minutes, reconnect, and try a simple microwave‑only heating cycle. If F08 appears immediately, the sensor circuit is likely faulty.
Step 2 – Locate the sensor: On Indesit combination microwaves, the cavity temperature sensor is usually mounted on the top or rear of the oven cavity, often behind a small metal cover.
Step 3 – Inspect wiring: With the cover removed, check the sensor wiring harness for damage, burns, or loose connectors. Reseat the plug at both the sensor and PCB ends.
Step 4 – Test sensor (advanced): Disconnect the sensor and measure its resistance with a multimeter at room temperature. Compare with the specification in the service manual. A reading of near 0 Ω (short) or infinite (open) indicates a failed sensor.
Step 5 – Replace sensor: If faulty, replace the NTC sensor with the correct Indesit part. Route the wiring away from hot surfaces and moving parts.

Note: If a new sensor does not clear F08, the control board input may be defective and require replacement.

Microwave shows F08 and will not start; grill or convection functions (if fitted) may also be disabled.

Possible Causes