The electrodynamic flow control effect using an applied magnetic field has a potential of innovative technology for aerodynamic force control of atmospheric entry vehicle because of no requirement of mechanical devices. To control this effect and aerodynamic force, we proposed a new approach using exposed electrodes on the vehicle surface. If the induced electric current is bypassed via exposed electrodes, the electromagnetic field could be changed. In this study, the influence of the partial electrical conducting wall, which is consisted of insulating and conducting walls, is numerically investigated. As a result of the MHD simulation, flow field could be changed by the vehicle surface condition. Especially, in the frontal region of the vehicle where strong Lorentz force acts, if the conducting wall is installed to electrically short to the shoulder position, the electric field within this region and the electrodynamic effect is significantly changed. Additionally, stepwise drag variation could be made by selectable shorted electrodes.