Match each control to the cavity diagram in the manual. Position alone is unreliable when several similar knobs share one long panel.
What the observation means
A temperature knob and a function knob can also belong to the same cavity. Labelling a problem 'the second knob' leaves its purpose unclear to someone who cannot see the cooker.
A useful next step
Record the cavity side, function name and temperature separately. If markings have worn away, obtain model-specific advice before heating. Do not identify unknown selections by turning each one on until a cavity becomes warm.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.