Display shows error shortly after selecting a cooking mode; oven does not start heating

Safety first: Disconnect power before removing the control panel.

• Check knob and shaft: Ensure the function knob is not cracked and that it firmly engages the selector shaft. Replace the knob if it slips or is damaged.
• Access selector switch: Remove the front control panel screws and gently pull the panel forward. Locate the function selector switch or encoder module behind the knob.
• Inspect for damage: Look for burnt contacts, melted plastic, or broken detents on the selector. Wiggle the wiring harness to ensure all connectors are seated firmly.
• Test continuity (mechanical switch types): Using a multimeter, verify that the correct contacts close in each selector position according to the wiring diagram. If contacts are intermittent or open in required positions, the selector is faulty.
• Replace selector/encoder: Disconnect the wiring harness, remove mounting screws or clips, and install a new Ariston function selector switch or encoder assembly. Transfer wires one by one to avoid misconnection.
• Reassemble and test: Refit the control panel, restore power, and verify that all modes can be selected without triggering the error.