Satisfactory operation performance of electrical systems depends heavily on different factors, namely sensors accuracy and system components. This paper presents easy fault detection, isolation method against currents measurement failure for grid connected photovoltaic system, were DC offset, and scaling errors are considered. This method does not need any extra hardware. It is based on analytical analysis of d-axis components of line current at the grid angular frequency ωg and 2ωg. These components are extracted through band pass filters in order to generate two residuals, which are employed for fault detection and isolation. Simulation results present the effectiveness of the proposed technique. An experimental platform was carried out to validate the obtained simulations results.