| 摘要 |
PROBLEM TO BE SOLVED: To provide a diagnosis device for surely detecting grand short-circuit between a linear solenoid valve and its driving circuit. SOLUTION: The driving circuit 2 consists of a switching means 3 for supplying a current to the linear solenoid valve 1 in accordance with an input ON-OFF signal to variably adjust a valve opening, a current detecting means 4 for detecting a current flowing from the switching means 3 to the linear solenoid valve 1, and a control means 5 for outputting the ON-OFF signal to the switching means so that the linear solenoid valve has a target opening in accordance with a current value detected by the current detecting means 4. The diagnosis device 10 diagnoses grand short-circuit between the driving circuit 2 and the linear solenoid valve 1. Herein, a grand short-circuit detecting means 5 is provided for detecting the switch-over of the ON-OFF signal to be input to the switching means 3 and for determining a trouble of the grand short-circuit when the frequency of ON-OFF switch-over per predetermined time is a predetermined frequency or less. COPYRIGHT: (C)2008,JPO&INPIT |
