| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately diagnose a fault of an exhaust emission control device including a catalyst having oxidizing capability. <P>SOLUTION: The fault diagnosis system includes: the catalyst disposed on an exhaust passage of an internal combustion engine and having the oxidizing capability; an oxidizing capability detection device for detecting the oxidizing capability in exhaust downstream further than the catalyst; and a diagnostic device for diagnosing a fault of the catalyst by comparing a value of oxidizing capability in the exhaust detected by the oxidizing capability detection device with a value of oxidizing capability in case the catalyst is in normal condition. Since the fault of the catalyst causes the oxidizing capability in the exhaust to be reduced, the system diagnoses the catalyst is in fault if the oxidizing capability in the exhaust is reduced. <P>COPYRIGHT: (C)2013,JPO&INPIT |
