Method for examining piezoelectric injector utilized as actuating element of valve of internal combustion engine in motor vehicle, involves classifying actuator unit as incorrect, when parameter exhibits deviation from preset value

摘要

The method involves determining impedance values for a set of frequency values within a preset frequency range. A characteristic attribute parameter of the impedance values is determined, where the impedance values are dependent on the frequency. Examination is made whether the characteristic attribute parameter exhibits a deviation from a preset expectation value. A piezoelectric actuator unit is classified as incorrect, when determined that the characteristic attribute parameter exhibits deviation from the preset expectation value. An independent claim is also included for a device for examining a piezoelectric actuator unit, comprising an impedance value determination unit.