| 摘要 |
An engine (1) is provided with a urea water supply mechanism (200) for supplying urea water to an exhaust passage (26). The urea water supply mechanism (200) includes a tank (210) for storing urea water, a pump (220) for delivering urea water, a supply pipe (240), a pump heater for heating the urea water in the pump (220), a passage heater for heating the urea water in the supply pipe (240), and a sensor for detecting the urea water pressure in the supply pipe (240). If the urea water pressure at the time when a drive signal is output to the pump (220) after initiation of heating control by way of the pump heater and the passage heater does not increase compared to the pressure before the drive signal was output, a controller (80) outputs a signal indicating an abnormality in the pump heater if the pump (220) is not operating and outputs a signal indicating an abnormality in the passage heater if the pump (220) is operating. |
