The China Locomotive Remote Monitoring and Diagnosis System (CMD System V2.00) is one of the core and fundamental subsystems in the locomotive information system of China State Railway Group. It serves as an integrated platform for data from various on-board systems of motorized train sets and locomotives, as well as a wireless transmission platform between the vehicle and the ground. It can achieve locomotive positioning, dynamic tracking of "person-vehicle-diagram", and conduct status monitoring, remote diagnosis, and troubleshooting of on-the-way locomotive equipment. In 2023, Chengdu Yunda completed the R & D of CMD System V2.00 under the unified deployment of China State Railway Group Co., Ltd. Compared with the first-generation product, the system utilizes new technologies such as Beidou Generation III, 5G, and WIFI6 to enhance data transmission capabilities. It isolates the information network and the control network of locomotives/motorized train sets through a security access board to prevent illegal access to the microcomputer control system.