A method for operating a Coriolis measuring device for measuring a density and/or a mass flow of a medium flowing through a pipeline, wherein the Coriolis measuring device comprises: At least one measuring tube for conducting the medium with one inlet (10.1) and one outlet (10.2), and one measuring tube wall (10.4) enclosing a measuring tube lumen (10.3); at least one exciter for generating measuring tube vibrations and one inlet-side first sensor (12.1) and one outlet-side second sensor (12.2) for detecting measuring tube vibrations, wherein the exciter and the sensors each have one coil device with at least one coil (13.1) and one magnetic device with at least one magnet (14.1), wherein the coil device and the magnetic device of each sensor are moved relative to each other by measuring tube vibrations, wherein an electrical measuring voltage is induced in the coil in the process; an electronic measuring/operating circuit for operating the exciter, for recording and analyzing the electrical measuring voltages, and for outputting measured values for density and/or mass flow and for diagnostics information, wherein the method has the following step: Recording the measuring voltages of the sensors and creating an asymmetry value sequence using the amplitudes of the measuring voltages for the purpose of performing diagnostics on the Coriolis measuring device, characterized in that the method has the following steps: Recording a measurement signal of at least one stabilization variable, creating a stabilized asymmetry value sequence based on the asymmetry value sequence as a function of the stabilization variable, wherein the stabilization variable is based on one of the following variables or a first or second time derivative: A resonant frequency of the measuring tube with medium or a variable derived therefrom, time or phase difference between measurement signals from the first sensor and the second sensor or a variable derived therefrom, temperature of the measuring tube wall, temperature difference between two measuring points on the measuring tube wall. At least one measuring tube for conducting the medium with one inlet (10.1) and one outlet (10.2), and one measuring tube wall (10.4) enclosing a measuring tube lumen (10.3); at least one exciter for generating measuring tube vibrations and one inlet-side first sensor (12.1) and one outlet-side second sensor (12.2) for detecting measuring tube vibrations, wherein the exciter and the sensors each have one coil device with at least one coil (13.1) and one magnetic device with at least one magnet (14.1), wherein the coil device and the magnetic device of each sensor are moved relative to each other by measuring tube vibrations, wherein an electrical measuring voltage is induced in the coil in the process; an electronic measuring/operating circuit for operating the exciter, for recording and analyzing the electrical measuring voltages, and for outputting measured values for density and/or mass flow and for diagnostics information, wherein the method has the following step: Recording the measuring voltages of the sensors and creating an asymmetry value sequence using the amplitudes of the measuring voltages for the purpose of performing diagnostics on the Coriolis measuring device, characterized in that the method has the following steps: Recording a measurement signal of at least one stabilization variable, creating a stabilized asymmetry value sequence based on the asymmetry value sequence as a function of the stabilization variable, wherein the stabilization variable is based on one of the following variables or a first or second time derivative: A resonant frequency of the measuring tube with medium or a variable derived therefrom, time or phase difference between measurement signals from the first sensor and the second sensor or a variable derived therefrom, temperature of the measuring tube wall, temperature difference between two measuring points on the measuring tube wall. Recording a measurement signal of at least one stabilization variable, creating a stabilized asymmetry value sequence based on the asymmetry value sequence as a function of the stabilization variable, wherein the stabilization variable is based on one of the following variables or a first or second time derivative: A resonant frequency of the measuring tube with medium or a variable derived therefrom, time or phase difference between measurement signals from the first sensor and the second sensor or a variable derived therefrom, temperature of the measuring tube wall, temperature difference between two measuring points on the measuring tube wall. A resonant frequency of the measuring tube with medium or a variable derived therefrom, time or phase difference between measurement signals from the first sensor and the second sensor or a variable derived therefrom, temperature of the measuring tube wall, temperature difference between two measuring points on the measuring tube wall.