July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!
Module Power, Ground, Data Communication, Control Switch, and Liftgate Motor
WARNING: This page is about a different car, the 2013 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Module Power, Ground, Data Communication, Control Switch, and Liftgate Motor Wiring Schematic