This dissertation contains the results of a 6 month-long internship at Maserati S.p.A. , in the Proactive Quality department, as a member of the team chassis. More specifically it aims at explaining , in a clear and easily understandable way, the process of resolution of a quality problem affecting the braking system of some models of the group. The extent of the study starts with the identification of the problem and ends with the identification of the root cause originating it. Explaining in detail the steps undertaken throughout each single phase of the project, with the ultimate objective of identifying the root cause of the problem and proposing some countermeasures.