Since first introduced in the middle of 1990’s, brake system with electric control transmission, called ‘Brake by Wire’, have gradually started to embodied in a complex braking system like EHB, EMB because its lots of benefits . But, there will be some safety-related risk if we use the system without consideration of electric failures. In this study, along with analysing international harmonization regulations(UNECE Regulation 13-H), a vehicle equipped with partial electric control transmission have been tested according to the present KMVSS No.90-1 for brake system and surveyed braking response on surfaces having different friction coefficient after setting various electric signal failure mode in hydraulic control unit, and the result of the study will be reflected on the KMVSS in future.