In an inspection procedure of a completed product of an automatic transmission main body at a unit factory, a control system transmits a control signal to an actuator to receive characteristic data (hardware performance information) output in response to operation of the automatic transmission main body according to the control signal. The hardware performance information of the automatic transmission main body is brought into correspondence with hardware identification information, and set in a database as learning value data. The learning value data of the automatic transmission main body is transferred to a vehicle factory to be aggregated in a database management system at the vehicle factory. When the automatic transmission main body is assembled with an electronic control device, learning value data of the automatic transmission main body is read out based on the hardware identification information from the database management system, and written into an AT_ECU during the inspection procedure of a completed vehicle at the vehicle factory.