First part of master thesis explains theoretical background used for proposed method. Root – cause analyse, DSM modelling, and methods for DSM analysis are explained in brief. In second part of thesis proposed method is described in case study of the shaft. Case study brings short explanation about parameter - based DSM modelling, relationship strength quantification, and analysis of numerical parameter - based DSM model for problem cause identification. Last part of this thesis is application of proposed method on ALSTOM company problem.