The invention relates to a method for connecting a pipe (3) for liquid or gaseous media with a plug connector (4), wherein a first casing section (12) of the plug connector (4) is deformed by means of a pressing tool in such a way that a pipe (3) positioned between the first casing section (12) and a second casing section (15) of the plug connector (4) is clamped. During the pressing process, the pressing force applied to the pressing tool is detected and a pressing force increase per unit of path length is calculated from the travel of the pressing tool and the pressing force. The detected pressing force increase per unit of path length is compared to a minimum required pressing force increase per unit of path length, and in the event, that the determined minimum required pressing force increase per unit of path length is not met, the plug connector (4) is identified as faulty.