in the era of today's polluted cities, hybrid vehicles have become necessary. They help in cutting down emissions and also improve fuel economy. Higher cost limits commercial viability of hybrid vehicles. Hence, a large number of OEM's are coming up with Mild Hybrid vehicles. This paper explains about one such mild hybrid application, a 12V BSG (Belt Driven starter generator) which works as a smart motor-alternator device. The BSG assists the engine while acceleration, enables start-stop function and also converts kinetic energy of vehicle into electricity during deceleration. This paper focuses onBenchmarking and Target setting of a Belt Driven Starter Generator (BSG) for FIAT 2.0 L Multijet Diesel Engine.