In this work, a novel and innovative methodology for evaluating the operational range of power modules in terms of current and power capabilities, based on electro-thermal transient simulations is presented. The innovation of the proposed method lies in its ability to integrate multi-domain simulations into a unified workflow, combining finite element thermal modeling, parasitic extraction, and system-level power loss computation. This integration enables a comprehensive and accurate assessment of the dynamic electro-thermal behavior of power modules under realistic loading conditions. The goal is to estimate the working conditions of a power module over time, providing a current-versus-time profile that the device can sustain without exceeding critical thermal limits.