The guiding thought under the fault safety was expounded, through qualitative analysis, the fault safety was controlled in different levels. For the first time, the guidance safety strategy was divided into SOL 1-4 levels. It was analysed that how to hand over the control taking over right to the driver in case of fault. Carry out necessary and correct guidance safety protection control in view of various faults of locomotives, according to the content and state of the fault, and guide the train to manually take over, slow down or stop. The test shows that HX,D,1 locomotive automatic train driving system achieves the purpose of the safety and smooth operation of the train.