Abstract: Vehicle door system is for passengers to get on and off, also an important barrier that protects passenger safety. To lower the failure rate of door system communication, the door system communication mechanism is expounded and the process of realizing train communication network control on doors is analyzed. The door system uploads the door status information and fault information to the TCMS (train control and management system) through MVB (multifunction vehicle bus), and displays door status on the HMI (human machine interface). Targeting the typical failure cases of HMIwarning door system communication abnormality, failure causes and treatment measures are sorted, and specific improvement suggestions are provided.