A method and a relative test structure for measuring the coupling capacitance between two interconnect lines exploits the so-called cross-talk effect and keeps an interconnect line at a constant reference voltage. This approach addresses the problem of short-circuit currents that affect known test structures, and allows a direct measurement of the coupling capacitance between the two interconnect lines. Capacitance measurements may also be used for determining points of interruption of interconnect lines. When a line is interrupted, the measured coupling capacitance is the capacitance of a single conducting branch. The position of points of interruption of an interconnect line is determined by measuring the coupling capacitance of all segments of the line with a second conducting line.