| 摘要 |
<P>PROBLEM TO BE SOLVED: To interrupt power transmission at failure in changing shift positions with appropriate timing, in a vehicle equipped with a by-wire type shifting device for changing shift positions of an automatic transmission by an actuator. <P>SOLUTION: The fail-safe control interrupts the power transmission from a driving source to a driving wheel by releasing the clutch of the automatic transmission at the time of a failure in shifting. When the hydraulic fluid of the automatic transmission is at a low temperature (for example, below freezing), the viscosity of the hydraulic fluid is too high, and the response of the power interruption becomes low. By taking this into consideration, when the oil temperature at the time of a request for shifting is at low temperature (steps ST2 to ST3), the clutch of the automatic transmission is released simultaneously with the request for shifting, and power transmission is interrupted (step ST11). Thus, a delay in the release of the clutch at the time of a failure in shifting with a low oil temperature can be prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT |
