Torque transmitting device control strategy for a nine speed transmission

摘要

A transmission includes an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. The transmission input member is connected to a dry launch clutch. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices are for example clutches and brakes. A hill hold control strategy is provided for locking the transmission without using the dry launch clutch by selectively engaging combinations of the clutches and brakes.