I also have OEm headrests with pioneer avic-z1 unit. So far had no luck, but will keep loking and will keep posted if i find anything.
If i dont find any answers ill just start experimenting with the lil jumper box to see what is what. It would be easier to do that if I could get a male for the connector pictured bellow. It would be easier to work with. Anyone know this connector type: (the big white one)
Also took some more pics of the Box that the two headrest dvd units connect to, and the other connectors
HummerNewbie, which pioneer do you have?