Train fault diagnosis method and device and train display

The invention discloses a train fault diagnosis method and device and a train displayer, and the train fault diagnosis method comprises the steps that train operation data transmitted by all devices contained in a train control system are obtained in real time, a dynamic polling algorithm is applied to detect fault information in the train operation data, and a fault list is generated; receiving a fault diagnosis request of a user based on any fault information in the fault list; performing feature processing on the fault information in response to the fault diagnosis request, and drawing a fault curve; and according to the fault curve, using a preset diagnosis algorithm to carry out fault positioning, and obtaining a fault diagnosis result. According to the train fault diagnosis method, the actual running condition of the train is considered, the polling priority of each device in the current polling period is dynamically updated in combination with the change of the device state in each period, the load bal