No Torque Converter Clutch Apply

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

Checks	Causes
Torque Converter Assembly (1)	Diagnose torque converter for possible internal damage.
Fluid Pump Cover Assembly (219)	Inspect for worn, damaged, or sticking converter feed limit valve (220) and spring (221). Inspect for worn, damaged, or sticking TCC control valve (227) and spring (226). Inspect for damaged stator shaft.
Control Valve Lower Body Assembly (307)	Inspect for worn, damaged, or sticking torque converter clutch (TCC) regulator apply valve (355).
4-5-6 (with Turbine Shaft) Clutch Assembly (56)	Inspect for damaged turbine shaft. Inspect for damaged turbine shaft O-ring seal.