If you define a resource cost in a part's ModuleSystemHeatRadiator, while the radiator will consume resources as defined, upon depletion of the required resources the radiators do not shut down, prevent you from activating them, or otherwise stop providing cooling power in any way despite displaying a UI warning.
If you define a resource cost in a part's ModuleSystemHeatRadiator, while the radiator will consume resources as defined, upon depletion of the required resources the radiators do not shut down, prevent you from activating them, or otherwise stop providing cooling power in any way despite displaying a UI warning.