Abstract: The complex operation environment of railway transportation in China has brought great tests to locomotive operation safety and automatic driving safety protection control. In view of the application requirements of freight locomotive automatic driving system in the special scenario of Xinfengzhen Station-Ankang East Station of Xikang (Xi'an-Ankang) Railway combined with the requirements of air braking application rules and driver control habits, this paper introduced the research and application of the control method for through test of automatic driving system. The operation test of the freight locomotive automatic driving system in Xikang Railway shows that the control method plays an effective role in monitoring, inspecting and confirming the functional integrity of the train air braking system, achieves the expected effect, and provides an important protective guarantee for the safe operation of the train under the automatic driving control mode.