Conditions for Setting the DTC: P0742
WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The TCM commands TCC ON, and the TCC slip is between -20 RPM and 30 RPM for 6 seconds, 3 times during the same ignition.