Oven display shows F12 and the clock/timer functions may be erratic or reset unexpectedly.

Safety first: Turn off power at the breaker before inspecting wiring.

Checks:

• Verify that the household supply voltage is within the specified range for the oven (typically 220–240 V AC) using a qualified electrician if needed.
• Inspect the oven terminal block for loose or discoloured connections; tighten screws and replace the block if heat-damaged.
• Check the mains cable for cuts or crushed sections.
• If external wiring is sound, the internal low-voltage supply on the control board may be failing; replacement of the control module is usually required.

Because this involves mains voltage and internal electronics, non-professionals should limit work to visual inspection and call a technician for board replacement.