We developed to have an automatic transferring function of a two-motors-driven electrical scooter for women or seniors to use conveniently it since it has been previously to operate it in manual only. The function would be implemented by using master and slave micro-control units(MCU) in the system with the given input and output signals. The simulation and test of the system results show that the transition conditions of either higher accelerating speed and/or higher torque are demonstrated at the worst conditions, which means that the transition points might be set either at the 70% of accelerating speed or from the 100% of load torque. The developed equipment is very useful and has good performance in the real test and would be used for top brand and might be applicable to any other types of green cars.