Transmission Control Module (TCM) Replacement
WARNING: This page is about a different car, the 2009 GMC Canyon and 2009 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.
If the TCM is replaced, TCM Reprogramming must be performed. Requiring special tool EL-49642 SPS Programming Support Tool and Tech 2. See Service Programming System (SPS)