Hi there, if you have a stock setup such as rns or rcd variants, then the module (in the right rear of wagon) provides power to the camera (when reserve is engaged, obviously enough) and camera sends video feed (ntsc format) to the camera module and in turn that is sent to the head unit. (There's power and video from the module to the camera through the hatch grommets).
If you're planning an OEM upgrade such as MIB, you can use the original video cable and power wiring (as noted above) to power a new camera (8V0) from a new module such as a 7N0.
Hope that assists
R36 Wagon MY2010.5: Biscay Blue| Dynaudio and Nav| RVC| VW tow bar|
Mod highlights: ECU and DSG Tune| 3AA CCM and 7N0 Gateway| 3D colour MFD| MIB2 retrofit and 7N0 RVC| Quad LED tail, brake and indicator rings| Zimmermann Sportbrake rotors, composite pads| TPMS High| 2Q0 Blind Spot and RCTA| B8 rearview mirror|
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