Torque Converter Clutch (TCC) Solenoid
WARNING: This page is about a different car, the 2008 Ford Pickup, 2008 Ford F550 Super Duty, 2008 Ford F450 Super Duty, and 2008 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The Torque Converter Clutch (TCC) solenoid is a directly proportional Variable Force Solenoid (VFS). The pressure output of this 3-port device is proportional to the applied direct current supplied through an electronically controlled driver which varies the current between 0 and 1 amp from the PCM.