An empty drum does not reproduce the moisture, fabric movement or sensing conditions of a suitable laundry load. Its duration or heat is therefore not a dependable standalone performance test.
Understanding this situation
Some programmes respond to the contents, and model behaviour varies. Running repeated empty hot cycles can also be unsuitable when a fault or safety concern is already present.
A useful next step
Use observations from ordinary permitted use and record the load and settings. Let the engineer choose appropriate tests. Do not infer a particular failed part because an empty cycle ended quickly or the cabinet felt different without laundry inside.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.