An apparatus for pumping a fluid by means of a piezoelectric pump is provided. All moving parts, including the valves and core, are piezoelectrically motivated. The preferred embodiment includes a piezoelectric ceramic tube having conductive bands adhered to the outer surface. The conductive bands and an inner surface electrode define tube regions which serve as valve and reservoir pump regions. A sensing circuit senses the voltage on the outer electrodes of the innermost of the piezoelectric regions to detect the presence of faulty pumping operation. The sensing circuit utilizes the piezoelectric effect that results from internal loading of the core.