Follow the exact model's instructions. Cooker grills differ, and an open-door rule from one appliance must not be transferred to another.
What the observation means
The permitted position can affect cooling, control temperatures and the cooking arrangement. A combined oven-grill cavity may use a different rule from a separate grill on the same cooker.
A useful next step
Identify the grill type before use and keep its door in the stated position. If the manual and actual appliance do not match, obtain clarification. Do not wedge a door or bypass a switch to make the grill operate contrary to its intended arrangement.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.