| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a NOx sensor rationality diagnosing device, a NOx sensor rationality diagnosing method, and an exhaust emission control device provided with the NOx sensor rationality diagnosing device, which diagnose rationality of a NOx sensor at a desired timing without deteriorating driveability and fuel consumption even during operation of an internal combustion engine. <P>SOLUTION: This NOx sensor rationality diagnosing device diagnosing rationality of the NOx sensor arranged downstream of a reduction catalyst includes: a sensor value storage section monitoring transition of a sensor value detected by the NOx sensor; a reducing agent supply instruction section instructing a supply of a reducing agent so that a predetermined amount of ammonia is led to flow out to the downstream side of the reduction catalyst; and a rationality determination section determining the rationality of the NOx sensor by determining whether the transition of the sensor value is changed in response to the fact that the predetermined amount of ammonia is led to flow out to the downstream side of the reduction catalyst. <P>COPYRIGHT: (C)2009,JPO&INPIT |
