The purpose of this study is to evaluate on a real urban driving cycle the performance of a plug-in hybrid-electric vehicle, which is part of a series of pre-marketing vehicles, taking into account the real driving conditions. For this purpose have been considered the driving style influence, the traffic level, the path slope and the comfort level requested inside the vehicle by the driver. In particular the influence of auxiliary systems consumption on the total consumption of the vehicle has been evaluated. Attention has been paid to assess the effect of auxiliary systems consumption on the autonomy of the vehicle on electric mode. The data were collected under real driving cycles in the city of Rome. The importance and innovation of this work consist of two principal concepts: (i) the auxiliary systems consumption and its influences on total consumption and (ii) the acquisition analysis under real driving cycle. Different drivers were involved during the acquisition campaign along several itineraries characterized by the features of a real urban cycle (length, slope, traffic light posts, etc.). The data acquisition was carried out on-board in real time using a measurement chain which included: OBDII (On - Board Diagnostic systems - second version), hardware, laptops and software. Acquired parameters were: traveled distance, speed, air flow, equivalence ratio, RPM, voltage, SOC (State Of Charge) of the batteries. The calculated variables from acquired data were: fuel consumption, consumption and incidence of auxiliaries on the autonomy in electric drive