Lock Up Pressure Control Solenoid Valve (SLU)
WARNING: This page is about a different car, the 2009 Pontiac Torrent and 2009 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.
The lock up pressure control solenoid valve is de-energized, allowing lock up control (12) fluid and TCC signal (13) fluid to exhaust through the solenoid.