Patent ID: 6996499

Claim:
A gas sensor abnormality detecting device made to detect the presence or absence of abnormality of a gas sensor having a cell in which a pair of electrodes are formed on a solid electrolyte material to output a signal corresponding to a composition of a measured gas on surfaces of said electrodes through a signal line connected to said electrodes, said device comprising: signal inputting processing mechanism for temporarily inputting a test signal including an alternating-current component through said signal line to said cell undergoing abnormality detection, said alternating-current component being above 1 kHz; response signal detector for detecting a response signal developing in said signal line in response to the inputting of said test signal; and decision processing mechanism for comparing a detection value of said response signal with a prescribed value and, if said detection value resides in one of regions defined by said prescribed value, making a decision that a disconnection abnormality occurs in said cell undergoing the abnormality detection.