The embedded flash technology can be subject to complex defects creating functional faults. In this paper, we describe the different steps in the electrical modeling of 2T-FLOTOX core-cells for a good understanding of failure mechanisms. First, we present a first order electrical model of 2T-FLOTOX core-cells which is characterized and compared with silicon data measurements based on the ATMEL 0.15 mum eFlash technology. Next, we propose a study of resistive defect injections in eFlash memories to show the relevance of the proposed simulation model. At the end of the paper, a table summarizes the functional fault models for different resistive defect configurations and experimental set-ups. According to these first results and with additional analysis of actual defects presented in [1] we are then able to enhance existing test solutions for eFlash testing.