Thermal Management Integration Module (TMIM), which comprises components such as water pumps, runner boards, brackets, sensors, etc., is a multifunctional integrated component for electric vehicles. However, the water pump generates an excitation over a wide range of frequencies due to a wide range of speed variations. This excitation causes the TMIM to vibrate and generate noise. In this study, a TMIM that generates noise is studied and analyzed. Using the TMIM of an electric vehicle as a case study, a full-vehicle experimental test was conducted, revealing that the noise originates from the integration module. The finite element method is used to analyze the cause of noise generation. Given the characteristics of the TMIM, which comprise many components, high integration, and a complex structure, this paper simplifies the bracket, heat exchanger, sensor, and other components using the centralized mass point method. The modal state of the TMIM is obtained by impact hammer testing the TMIM and then compared with the modal state calculated by the finite element method to verify the feasibility of the finite element method. An optimization scheme was developed based on the results of the analysis. Finally, the optimized TMIM was tested. The results show that the proposed method can reduce the computational cost and meet the computational accuracy requirements. The method is effective in predicting noise sources, solving noise-related issues, shortening the design cycle, and reducing the cost of real-vehicle testing.