The windshield wiper, as a critical subassembly for vehicle vision cleaning, plays an essential role in ensuring passenger safety. However, due to the specific structural characteristics and spatial layout of the wiper, it is positioned within the pedestrian protection headform test zone, thereby significantly influencing pedestrian protection safety ratings. To elucidate the impact of wiper components on the head injury criterion (HIC) derived from headform tests, this paper examined a total of 35 headform test points across various vehicle models within the company. We analyzed the primary reasons for the significant increase in HIC values in the wiper areas, which could facilitate the establishment of a correlation analysis mechanism between the spatial dimensions of the wiper regions and HIC. The paper explores the possibility of determining collision energy conversion efficiency based on the integration of synthetic acceleration-displacement (G–D) curves and proposes four spatial optimization strategies in accordance with the energy distribution patterns during collision intrusion. Through a synergistic analysis of energy conversion, the influence mechanism of these four optimization schemes on the HIC in the wiper regions can be deduced. The ultimate goal of this paper is to redesign the spatial layout of the wiper regions and develop related auxiliary subassemblies based on energy conversion scales. By controlling the energy distribution across various segments of the G–D curves, the aim is to reduce HIC injuries in the wiper regions, offering insights for the multi-scale optimization design of these areas.