Speed change control apparatus for an automatic transmission

摘要

A speed change control apparatus of an automatic transmission has a transmission control unit. When determining a fault of a power-on/off determining section on the basis of engine load information from an engine control unit, the transmission control unit controls an oil pressure controller by regarding an engine as being in a power-on state in upshifting and by regarding the engine as being in a power-off state in downshifting. As a result, in either of upshifting and downshifting, the moment when a disengagement-side friction element of the transmission begins to slip and the moment when an engagement-side friction element is engaged are made proper. This makes it possible to surely prevent undesired rise in the engine rotation during the speed change in upshifting and inability in speed change in downshifting, which are caused by a fault of the power-on/off determining section.