This paper deal with due to the additional equipment established on the vehicle fire accident cases. Recently, vehicle was recognized as other living spaces and it was increasing installation of additional devices such as a black box, multivision, additional battery and so on. However, these additional devices were established on the vehicle by non-specialists such as the general public user or manufacturing and distributors of additional devices since the vehicle factory. Resulting from the additional equipments due to installation errors in these additional equipments connected to the electrical wiring insulation damage or electrical breakdown occurs, and finally leading to a fire caused by the additional equipments. Therefore, additional equipment established on the vehicle due to a fire in order to prevent accidents during the manufacturing process of these devices are installed. If not installed unless the manufacturing process, the installation of additional equipments established by professional who knows the vehicle structure that will be able to prevent the fire.