| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a failure diagnostic device for a particular filter, which performs failure diagnosis of the particulate filter at higher accuracy. <P>SOLUTION: The failure diagnostic device compares a value detected by a PM sensor provided on the downstream side of the particulate filter with an estimated sensor PM accumulation amount to discriminate the presence or absence of a failure in the particulate filter (S112-S115). At this time, it executes the discrimination of the presence or absence of the failure in the particulate filter on condition that the ratio of a significant estimated sensor PM accumulation amount which is estimated in accordance with an integrated value for only flow-out PM amounts integrated when there is a great difference between the flow-out PM amounts in the normal state of the particulate filter and during a failure thereof, to the estimated sensor PM accumulation amount is a reference ratio or higher (S111). <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
