Aiming at the limitation of traditional electronic standby control mode for car, a new type electronic standby control mode for car based on Profibus-DP is probed. With the mode, only an ECU is needed to achieve the whole systemic standby control. The standby control mode, the system function, the rules achieving Profibus-DP slave station and the design scheme of software and hardware are discussed. The feasibility and reliability for the mode are verified through the results of experiments.