FIELD: checking and diagnosing computer-aided control systems. SUBSTANCE: method and device are meant for diagnosing dynamic sections inserted in feedback circuit. Diagnostic entity is system that has two dynamic feedback components. Method involves pre- determination of entity check time, integration of input test signal and signals picked off entity outputs, determination of estimates of entity transfer functions, computation of diagnosing parameter of second dynamic component, determination of rated value of second-entity diagnosing parameter, computation of first-entity diagnosing parameter, and determination of rated value of first-entity diagnosing parameter; serviceable entity is replaced by that to be diagnosed and, using above-found parameters, diagnosing parameters of dynamic components are determined by above-described method; faults are recognized by their deviation from rated values. Device implementing this method has triggering circuit, test signal source, nonlinear function generator, first unit of entity being diagnosed, second unit of entity being diagnosed, three multiplying units, three integrating units, four dividing units, three adders, two tolerance check units, and two amplifiers. EFFECT: enlarged functional capabilities. 2 cl, 4 dwg
