This paper presents a modification to increase the robustness of the methodology used to eliminate the multiple estimation problem, of fault location methods based on the impedance estimation. The approach here proposed uses the power system parameters and the available measurements at the main power substation. Tests are carried out on different power systems, analyzing the effect of fault resistance and load current on the fault location. The obtained results show that it is possible to obtain a unique fault location, eliminating the multiple estimation problems even in the case of 40 Ω impedance faults. This method also helps to improve the power continuity indexes in power distribution systems by the determination of the faulted node.