Confirmed, the radio does power on when the vehicle is not turned on or even have the key in the ignition.
I tried with the PIU harness and the civilian one, without the paddle shifters being attached. Neither got the switches to work. I checked the wiring diagram book I have and there are no different diagrams for the controls... Incidentally the part number printed on the back of both the civilian control and the PIU control was the same.
Point of info, even the cruise control buttons which are common among the 2 controls failed to work. So I suppose its possible that the control is broken.
I do not know how to program the buttons, I was attempting to see if I could activate the civilian controls by changing the left control model number in the SCCM in Forscan. There are multiple options with similar part numbers and variant -x at the end. For example the part number on all 4 controls is listed as L8A1F-9E740, both left and right sides and both civilian and PIU left control.
In Forscan under the SCCM the left control is listed as LB5T-9E740-B* while the right is H1BT-14K147-A* / LB5T-9E740-D*. But I could not set any other options for either the left or right control as Forscan failed saying there was an error.