The invention provides a method of controlling an ink jet recording apparatus on which a liquid container is to be detachably mounted, the liquid container having a piezoelectric device for detecting the liquid. The method includes the steps of: detecting a characteristic value of the piezoelectric device by a detection section provided inside or outside of the ink jet recording apparatus; judging whether or not the characteristic value satisfies a predetermined condition by a judging section provided inside or outside of the ink jet recording apparatus; and controlling the ink jet recording apparatus so that the ink jet recording apparatus is set in an operable or a non-operable state based on a result of the judging step. It is possible to judge whether or not the piezoelectric device is normally operated, to confirm the liquid of the predetermined volume is contained in the liquid container, to detect deficiencies of the liquid container and the piezoelectric device, and to detect a gradient of the liquid container.

 
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