Patent ID: 11125323

Abstract:
Selection solenoid valve (75) controls engagement/disengagement of travel clutch (31, 32) in synchronization with a selecting operation of selector lever (90) that selects a range position of belt-type continuously variable transmission (CVT). Selection solenoid valve abnormality diagnosing unit (8a) is configured to, when performing a selecting operation from no-drive range to drive range, if a time required for travel clutch (31, 32) to be judged to be engaged from a start of selection of the drive range is less than a predetermined time, judge selection solenoid valve (75) to be a maximum hydraulic pressure side abnormality. When performing the selecting operation of drive range→no-drive range→drive range, if a selecting operation speed condition indicating that a no-drive range selection time is shorter than a setting time (Tth) is satisfied, execution of abnormality diagnosis of selection solenoid valve (75) is not permitted. With this configuration, misjudgment is prevented.