DIAGNOSTIC DEVICE AND SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a diagnostic device and a sensor which can early detect a functional defect and functional deterioration of a PM sensor at a low cost.SOLUTION: A diagnostic device of a sensor 10 which is arranged in an exhaust passage 110 of an internal combustion engine 100 and detects an amount of particulate matters in exhaust comprises: a time change rate operation section 2 which obtains a time change rate of the amount of the particulate matters detected by the sensor 10 during a period when a fuel injection amount of the internal combustion engine 100 is not more than a predetermined injection amount threshold; and an abnormality determination section 3 which determines abnormality of the sensor 10 on the basis of the time change rate of the amount of the particulate matters obtained by the time change rate operation section 2.SELECTED DRAWING: Figure 1