CONTROL DEVICE FOR AUTOMATIC TRANSMISSION AND CONTROL PROGRAM FOR AUTOMATIC TRANSMISSION

摘要

A control device for an automatic transmission including a neutral control unit that executes neutral control for bringing the automatic transmission into a neutral state by reducing an engagement force for an engaged frictional engagement element; a speed ratio specifying unit that specifies an actual speed ratio of the automatic transmission on the basis of a rotating speed of an input shaft and a rotating speed of an output shaft; and a first failure determination unit that determines whether or not a failure is occurring in the automatic transmission on the basis of the actual speed ratio during execution of the neutral control. The first failure determination unit determines that a failure is occurring in the automatic transmission in the case where the actual speed ratio coincides with the speed ratio of any one of a plurality of shift speeds over a predetermined time.