Patent ID: 8226532

Claim:
A control apparatus for an automatic transmission having a rotation transmission mechanism for transmitting rotation of a prime mover mounted on a vehicle to a speed change mechanism and an input clutch for controlling connection and disconnection of the rotation transmitted from the rotation transmission mechanism, the control apparatus comprising: a control portion that performs a neutral control including a release control that reduces a fluid pressure relative to the input clutch so as to reduce rotation transmission efficiency from the rotation transmission mechanism side to the speed change mechanism side via the input clutch when the vehicle is stationary, and an in-neutral control that adjusts the fluid pressure relative to the input clutch so as to maintain the rotation transmission efficiency via the input clutch at a low efficiency, wherein the control portion performs, during the in-neutral control, a check control that makes the fluid pressure relative to the input clutch fluctuate and, when determining as a result of the check control, that the rotation transmission efficiency via the input clutch is in a predetermined state set previously as a low efficiency, reduces the fluid pressure relative to the input clutch at termination of the check control by a set pressure and thereafter keeps the fluid pressure constant.