Fault diagnosis method for motor lead screw driving door

The invention relates to a fault diagnosis method for a motor lead screw driving door. According to the method, fault diagnosis is conducted using characteristic parameters of a motor of a door system and combining current data collected by an electric car door control system (EDCU). Firstly, numerical differentiation is conducted on the collected data, a first-order derivative value and a second-order derivative value are obtained at the corresponding sampling points, after the first-order derivative value and the second-order derivative value are substituted into an electric equation, a motor output power variation rate is obtained, after a second discretization is conducted on the variation rate, a plurality of failure modes of the electric car door are identified by a rough set identification method.