| 摘要 |
<P>PROBLEM TO BE SOLVED: To correctly determine a closing failure of a selector valve, in a cooling system provided with a selector valve for limiting the circulation of a coolant between an engine coolant passage and a bypass passage. <P>SOLUTION: Even if the coolant temperature sensor of either an engine coolant temperature sensor 21 or a heater inlet coolant temperature sensor 22 (bypass coolant temperature sensor) cannot be determined normal or abnormal, a device for determining a failure of a selector valve determines that the selector value 10 is in a closing failure by using a normality determined coolant temperature sensor (engine coolant temperature sensor 21, for example) before carrying out the normality determination of the coolant temperature sensor that is not determined normal yet. Thus, the coolant temperature sensor abnormality can be discriminated from the closing failure of the selector valve by using the normality determined coolant temperature sensor (engine coolant temperature sensor 21, for example) without the use of the coolant temperature sensor (heater inlet coolant temperature sensor 22, for example) that is not determined normal or abnormal yet, so that the closing failure of the selector valve can be determined correctly. <P>COPYRIGHT: (C)2012,JPO&INPIT |
