The growing significance of photovoltaic (PV) monitoring systems and diagnostic methodologies is evident in their role in enhancing the power generation, efficiency, and durability of photovoltaic systems. The operational efficacy of these systems is primarily influenced by factors such as irradiation levels and cell temperature. Consequently, there exists a pressing need for dedicated scrutiny and scholarly investigation into the identification and diagnosis of defects within these systems, aiming for swift identification and rectification of failures in PV stations. This paper thus endeavors to introduce a diagnostic methodology focused on fault detection and categorization of eight types of faults occurring in shading, series resistance, shunt resistance, and bypass diode faults (disconnected, short circuited, shunted with resistor) within photovoltaic panels. This analysis employs two distinct algorithms: the initial algorithm employs the thresholding method, while the second algorithm is grounded in a Fuzzy Logic classifier (Sugeno model). Upon examination of the simulation outcomes, it becomes evident that the threshold method fails to identify all faults, necessitating the adoption of a more effective classification technique. Moreover, the Fuzzy Logic (FL) method has proven to be the most suitable approach for diagnosing PV module issues. The findings indicate that all specified faults are detectable in a discernible manner. These approaches have demonstrated proficient accuracy and efficacy in pinpointing and characterizing various faults within PV panels. Notably, our simulation endeavors were conducted utilizing Simulink/Matlab software.