| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a thermostat failure determining device capable of detecting presence or absence of a failure of a thermostat by monitoring warming-up performance of an engine at a cold start. <P>SOLUTION: The failure determining device for a thermostat 16 provided in a circulation path 13 for cooling water 12 of an engine 1 includes a water temperature sensor 18 detecting a temperature of the cooling water 12 having passed through the engine 1; and a control device 19 input with a detection signal 18a from the water temperature sensor 18 to monitor temperature rising of the cooling water 12 at a cold start, and calculating a predicted water temperature of the engine 1 from starting to determine a failure of the thermostat 16 if the temperature of the cooling water 12 is not exceeding a threshold when the predicted water temperature reaches a valve opening temperature of the thermostat 16. <P>COPYRIGHT: (C)2012,JPO&INPIT |
