The vehicle system is a multi-domain system that requires many branches of science and engineering. Therefore the development of the vehicle system requires the use of design methodologies that utilize simulations, which have grown increasingly sophisticated in recent years. Our research group proposed a simulation modeling method based on the VHDL-AMS language. This paper describes how VHDL-AMS is used to model of vehicle fuel consumption simulation. The fuel consumption is shown using proposed simulation model on the Japanese 10-15 mode. We examine the influence of the vehicle system with electrical load and hill climb resistance in the vehicle running resistance.