Circuit/System Verification
WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Verify that DTCs P0787, P0973, P0976, P2764 have not set, if so, diagnose first. With a scan tool, command the TCC Solenoid valve ON and OFF.