New trends were introduced in using photovoltaic (PV) energy which are mostly attributable to new laws internationally having a goal to decrease the usage of fossil fuels. The PV systems efficiency is impacted significantly by environmental factors and different faults occurrence. These faults if they weren’t rapidly identified and fixed may cause dangerous consequences. A lot of methods have been introduced in literature to detect faults that may occur in a PV system such as using I-V curves measurements, atmospheric models and statistical methods. In this paper, various machine learning techniques in particular supervised learning techniques are used for PV array failure diagnosis. The main target is the identification and categorization of several faults that may occur such as shadowing, degradation, open circuit and short circuit faults that has a great impact on PV systems performance. The results showed the techniques high ability of fault diagnosis capability. The KNN technique showed the best fault prediction performance. It achieves prediction accuracy 99.2% and 99.7% AUC-ROC score. This shows its superiority in faults prediction in PV systems over other used methods Decision Tree, Naive Bayes, and Logistic Regression.