| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust emission control system controller capable of detecting the generation of a precipitate while keeping actuating a motor for driving a urea water pump, and ensuring high detection responsiveness.SOLUTION: A determination unit 33 determines whether a precipitate is generated in a urea water passage portion 16 from the number of revolutions of a motor 18 detected by a number-of-revolutions detection unit 32. If the precipitate is generated in a urea water passage 21, the resistance of urea water flowing in the urea water passage 21 increases and the number of revolutions of the motor 18 driving the urea water pump 15 changes. The determination unit 33 determines whether the precipitate is generated on the basis of a change in the number of revolutions of the motor 18. As a result, it is possible to detect the generation of the precipitate while keeping actuating the motor 18 driving the urea water pump 15. |
