A member of the FB group is attempting headrest monitors because he basically got an entire Interior out of a 2011 Grange. I found some of the info on identifix that just copied a lot of the Australian service info over from the Australian caprices because they had not made a specific version for the US yet. And keeping with Holden's and GM's practice the service info is wrong again in this case. The left and right monitor plugs show a 14 cavity plug is used but they have a picture of an 8 cavity. Wonderful.
Looking at the service programming links seems to me it is going to be a tough haul to get it working. Says the DVD module only programs the region one time? and to make changes have to contact a division of GM for authorization and security code? And the DVD module is VIN locked. Might Need Chris White on this one!!
Anyway here is some info. Will add to it as I find more:
Headrest plugs:
You will see on the wiring diagrams there are 2 option designations (U56 and the other)
I think one is for when the car has the DVD player in the ceiling (flip down) but not the headrest?? Maybe?? I think only the longer cars (WM's) got the headrest monitors.
System Diagrams:
Here are some PDF's of the System Description and Module Programming.
System Description
Module Programming - Mentions getting TIS approval
Getting TIS Approval
Here are some code Trouble Shooting guides that go into further detail how the system talks to each other:
DVD Control Module Faults
Data Communications Faults
Screen Voltage Faults