<p>Premature electrical failures in rolling bearings have become one of the key bottlenecks in the development of electric vehicles (EVs), both now and in the coming decades. As a complex mechatronic system, the electric powertrain is subject to multiple excitation sources that influence its vibration behavior. Bearing electrical erosion damage (BEED) further intensifies this complexity, complicating fault diagnosis and hindering efforts to improve the reliability of EV powertrains. Therefore, understanding the dynamic impact of BEED is essential for developing effective monitoring and mitigation strategies. In this paper, a novel integrated mechatronic model is proposed to systematically analyze the influence mechanism of BEED on the vibration characteristics of the electric powertrain under various operating conditions. Firstly, the problem of BEED in EV transmission system is analyzed, the geometric features of damaged bearings are characterized, and a damaged bearing model is established. Then, based on a mechatronic framework, a comprehensive dynamic model is developed that captures the coupled effects of multiple excitations from mechanical, control system, and external excitation, and its accuracy is validated through experiments. Finally, the effects of damage dimensions and variable speed/load conditions on vibration responses of electric powertrain are investigated. The findings provide theoretical foundations for fault diagnosis and reliability optimization of highly integrated electric powertrain.</p>