The high-voltage system of new energy hybrid vehicles is prone to pose interference threats to the traditional low-voltage electrical circuits. This paper selects the low-voltage wiring harness of the fuel pump as the research object, examines the complete electrical circuit structure of the oil pump, and analyzes the internal mechanism by which the high-frequency impact current of the oil pump triggering failure of the low-voltage wiring harness conductors and insulation; combined with the current-carrying capacity of the wiring harness and the overcurrent verification design logic, it quantitatively assesses the risk of overcurrent thermal damage based on real vehicle cases, establishes a set of risk analysis process for impact overcurrent of the low-voltage wiring harness, and provides corresponding design durability life indicators for each electrical component of the oil pump link in the hybrid vehicle model.