3rd Gear: Powerflow
WARNING: This page is about a different car, the 2011 Ford Pickup, 2011 Ford F550 Super Duty, 2011 Ford F450 Super Duty, and 2011 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
In 3rd gear, SSA is commanded ON by the PCM/ TCM to apply the forward (1,2,3,4) clutch. SSB is commanded OFF by the PCM/ TCM to apply the direct (3,5,R) clutch. The forward (1,2,3,4) clutch connects the front carrier to the No. 3 sun gear and the direct (3,5,R) clutch is applied to transfer power from the front planetary carrier to the No. 2 sun gear, providing a 1.516 to 1 gear ratio.