| 摘要 |
Provided is a competence diagnosis system for a urea water temperature sensor that can prevent a misdiagnosis when urea water is replenished in a urea tank. A competence diagnosis system for a urea water temperature sensor 129 includes a competence diagnosis unit 127 that diagnoses a failure of a temperature sensor 121 provided in a urea tank 105 by comparing a urea water temperature measured by the temperature sensor 121 with an ambient temperature. The competence diagnosis system for a urea water temperature sensor 129 includes a urea water level condition determination unit 128 that stores a urea water level, which is measured by a level sensor 120 provided in the urea tank 105, in a storage unit 130 immediately before key-off, obtains a level difference between the urea water level stored in the storage unit 130 and a current urea water level after key-on, and allows a diagnosis by the competence diagnosis unit 127 through temperature comparison when the level difference is less than or equal to a predetermined threshold value. |
