AGA oven shows F12; one or more oven cavities do not respond to temperature settings.

Safety first: Disconnect the oven from mains power before removing the control panel or knobs.

• Check knob and shaft: Remove the function selector knob and inspect the shaft for cracks or rounding that could prevent proper engagement.
• Access selector switch: Remove the front control panel to expose the function selector switch. Look for signs of overheating or melted plastic.
• Test switch contacts: Using a multimeter, check continuity between the appropriate terminals in each selector position according to the wiring diagram. Lack of continuity where expected indicates a faulty switch.
• Inspect wiring: Ensure all spade connectors are tight and not heat-damaged. Replace any discolored or brittle wires.
• Replace selector switch: If contacts are burnt or intermittent, replace the function selector switch with an AGA-approved replacement.