| 摘要 |
PURPOSE:To surely detect the abnormality of a heat-sensing member by comparing the engine rotating speed with the preset value when forcefully opening an idle rotating speed control valve provided with an opening restricting mechanism restricting the maximum opening of a valve body with the heat-sensing member according to the ambient temperature. CONSTITUTION:An idle rotating speed control valve (ISC valve) M3 has a valve body M31 operated by a solenoid and an opening restricting mechanism M32 restricting its maximum opening with a heat-sensing member according to the ambient temperature and is controlled by a control means M5 in response to the operation state of an internal combustion engine M1 detected by a detecting means M4. The ISC valve M3 is forcefully opened by the preset opening for the preset time by a forced opening means M6 after starting, the engine rotating speed is compared with the preset value by a comparing means M7, if the engine rotating speed is larger than the preset value, a failure detecting means M8 detects that the ISC valve M3 has a failure. The abnormality of the heat-sensing member is surely detected, and the quick rise of the rotating speed due to an unexpected failure can be prevented. |
