ABNORMALITY DETECTION DEVICE FOR FUEL PROPERTY DETECTION DEVICE

摘要

In order to accurately diagnose the abnormality of a fuel property detection device for detecting the fuel property on the basis of the capacitance between electrodes, disclosed is an abnormality detection device for a fuel property detection device. Said abnormality detection device is a device for detecting the abnormality of the fuel property detection device for detecting the fuel property on the basis of the measured value of the capacitance between a pair of electrodes installed in a fuel supply path of an internal combustion engine that can use fuel containing a predetermined fuel component having a characteristic that the dielectric constant changes according to the frequency of an electric field, said abnormality detection device being characterized by being provided with: a frequency switching means which switches the frequency of alternating voltage to be applied between both the electrodes to a plurality of frequencies; a measurement means which measures the capacitance at each of the plurality of frequencies; a storage means which stores frequency characteristic information that is information relating to the relationship between the fuel property and the frequency characteristic of the capacitance when the fuel property detection device is normal, and a diagnosis means which, on the basis of the result of the measurement by the measurement means and the frequency characteristic information, diagnoses the abnormality of the fuel property detection device.