Certain programmes may not support probe-controlled cooking. A greyed-out option can therefore be an intentional restriction rather than a damaged sensor.
What the observation means
The oven's programme table determines compatible functions. A probe accepted in roasting may not be appropriate for grilling, cleaning or another special mode. Do not try to force access by entering hidden menus or using an adapter.
A useful next step
Check the supported combination before starting. If the approved mode still fails to recognise the correct undamaged probe, note the display message and connection state. Keep the probe out of cleaning cycles unless the manufacturer specifically states otherwise for that exact accessory.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.