| 摘要 |
PROBLEM TO BE SOLVED: To determine whether there is anything unusual in a cooling liquid circulation state in an outside passage for allowing a cooling liquid for a water jacket for an engine to be extracted and then returned.SOLUTION: An engine cooling device includes: an engine outside passage for allowing a cooling liquid for a water jacket of an engine to be extracted and then returned; a control valve for controlling a circulation amount of the cooling liquid for the water jacket; an electric water pump for circulating the cooling liquid; and a control part for controlling the electric water pump. The control part determines whether there is anything unusual in a cooling liquid circulation state in an outside passage based on a change in a rotation speed of the electric water pump when a driving duty of the electric water pump is constant. |
