| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable speed control apparatus of an automatic transmission that can perform safe and secure failure control by means of ascertaining surely the cause of the failure when such a failure occurs that an actual gear ratio is larger than that of a gearbox. SOLUTION: The variable speed control apparatus of an automatic transmission is provided with an actual gear ratio detection means for detecting the actual gear ratio of the automatic transmission, a failure judgment means, a failure check means for forcing to retaining for a predetermined time period, an off-state of a shift solenoid controlling actuation of a shift valve considered to have failed and checking the actuation of the shift solenoid, and a failure control means for memorizing failure of the shift solenoid and for performing failure-control established in advance. |
