The paper presents a mathematical model of the wheel vehicle drive system consisted with: special drive motor (radial induction motor, or PMSM motor) connected with drive transfer system, and drive elements (wheel axes). Magnetic fields distribution in traction motor, and tension of magnetic fields distributions in mechanical part of the vehicle are presented in the paper. Traction induction motors supplied with inverter decrease efficiency of the motor and sometimes present additional rotor and stator fault. Modern diagnostics method used of: FEM, BEA and random method has been used for faulty motor simulation and shows results of motor fault effects. Experimental results collaborate with the simulation and theoretical effects. ANSYS, JMAG and FEMM computer programs were applied in calculation of magnetic fields distribution for different faults state of the motors. On the base of magnetic field and force tension distributions were analyzed different failures situations and method of limitation their negative effects. Some laboratory experiments was realized for the traction motor.