Automotive product engineering is highly complex. Understanding the implications and opportunities of introducing new technology needs to be identified as early as possible in the vehicle design process. These earlier design considerations have the potential to deliver right-first-time designs and maximize integration opportunities, resulting in efficient, effective, competitive and holistic design solutions.Integrating new technology into existing vehicle architectures can preclude and restrain the opportunity for engineers to invent, discover and deliver new design solutions. To avoid this potential loss of opportunity, it is necessary to trace back to vehicle-level assumptions and attributes to confirm the technology delivers the desired output. The vehicle and system analysis enables engineers to consider all vehicle attributes and how their sub-system can enhance other vehicle systems.This paper describes a case study using Function Analysis, within a systems engineering framework applied to the design and integration of a 48V mild hybrid system (mHEV) for a diesel powertrain. The key deliverables were to improve fuel economy (CO2 reduction) through improved usage of stop/start technologies and the recuperation of kinetic energy during vehicle deceleration events. This case study also illustrates vertical integration of mHEV system functions to vehicle attributes. Further it supports a practical approach to the specific development of new innovative ideas using lateral thinking. It also shows the reliance on systems engineering within a multidisciplinary system concept design environment. This process will expedite model based systems engineering.