| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an abnormality diagnostic device for an exhaust temperature sensor capable of diagnosing abnormality such as a fault of an exhaust temperature sensor for detecting exhaust temperature under a wide range of conditions.SOLUTION: An oxidation catalyst (5) and a DPF (6) are provided in an exhaust passage (4) of an internal combustion engine (1), and exhaust temperature sensors (11a and 11b) are respectively provided upstream and downstream of the oxidation catalyst. An abnormality diagnostic device for exhaust temperature sensor according to this invention estimates an exhaust temperature at the downstream exhaust temperature sensor based on a detection value from the upstream temperature sensor, and compares the estimated value with a value actually measured by the downstream temperature sensor, and determines that the exhaust temperature sensor has abnormality when the deviation is larger than a prescribed value.</p> |
