| 摘要 |
<P>PROBLEM TO BE SOLVED: To easily diagnose degradation of a gas sensor such as a hydrogen sensor. <P>SOLUTION: The hydrogen sensor is provided with a reference detection element and a normal detection element. Each detection element is constituted of a pair of detection element and temperature compensation element. At normal times, the concentration of gaseous hydrogen is detected by the normal detection element by supplying power to the normal detection element. For degradation diagnosis of the normal detection element, power is supplied to both of the normal detection element and the reference detection element, and the concentration of a prescribed concentration of gaseous hydrogen is simultaneously detected by each of the detection elements. By comparing the output value of the normal detection element with the output value of the reference detection element, degradation of the normal detection element is diagnosed. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
