Abstract: To address the problems of lack of technical information on imported equipment RF modules, long repair cycles, and high repair costs, this study proposes employing ANSYS HFSS for modeling and repair analysis. The approach involves modeling and simulating the RF circuit, as well as simulating the faulty RF circuit module. By comparing the output parameters of the simulation model with those of the fault simulation model, the cause of circuit malfunction is identified, therefore the circuit faults is accurately located. The results show that this method can quickly simulate and compare the insertion loss, standing wave ratio, and other indicators of RF circuit in different states. Simulate and analyze the reasons for the decrease in impedance matching performance, signal transmission performance, and signal isolation performance of faulty RF circuits, and combine product fault parameters to quickly and accurately the fault reason. This method can shorten product repair time, avoid secondary damage caused by repeated disassembly and assembly of RF modules, improve product repair efficiency, and lower repair costs.