Hi guys, new to the site so hope this in the right place.
I've just bought a 2006 hummer h2 import and there are some bits not working.
The head unit is an aftermarket system so i think that could be the reason for some of it.
The rear console does not seem to have any power to it and there seems to be something missing:


The headrest monitors (hummer not aftermarket) work but do not display anything so i doubt they are connected to anything.
This cable is poking out from the rear console, can anyone identify it?

It appears to have a live and a negative and what looks like either an aerial connection or an av connection. not sure if it is linked with the monitors etc.

Any help would be welcome.
thanks
Niall