Diagnostic module for testing the tightness of a container

Abstract

In a diagnosis module for leak testing a container of a tank ventilation system of a motor vehicle, which has a reference leak through which a volume flows and is matched to a permissible leakage of the container. The reference leak is constituted by a number of diaphragms disposed in series in the flow direction, in which each of the diaphragms have a throttle opening (25 27). The advantage of this diagnosis module lies in the large diameter throttle openings, which are less susceptible to malfunction when there is a permitted leakage hole that has a significantly smaller diameter.

Dependencies are inferred from the claim text.