The reliability of electrical connections becomes a crucial issue, because more and more connecting cables are involved in modern engineering systems. In this demo, the tested cable is a twisted pair of 10 meters, with faults created during the demo by locally untwisting the cable. Easily reparable for the purpose of demo, such geometrical deformations are soft faults, since they do not cause impedance discontinuity in the cable. A network analyzer connected to one end of the cable collects spectral data, which are processed by an algorithm in real time to estimate the characteristic impedance profile distributed along the cable. The faults created during the demo are detected, localized and quantified in real time through the estimated characteristic impedance profile. As the impedance estimation algorithm does not make any assumption about the shape of the characteristic impedance profile, this method is particularly suitable for the diagnosis of multiple and distributed faults. The demo will be shown in real time with a true cable connected to a network analyzer. A video is available online.