The Golf can have the factory reverse system from other models (generally Tiguan 5N0) installed, there are a few caveats that must be checked first as some components in the car must be a particular revision or higher.
Gateway needs to be 3C0 907 530 H or higher. For the Tiguan or Passat controller you need to use a 9-byte long CAN gateway (L or N at the end), the Touareg controller may only require a 8 byte controller.
Kufatec sell a harness that connects the RNS510 to the reverse camera controller for 89 euros.
Parts required for install (not using the hatch/boot release detailed below)
Reverse Controller Tiguan- 5N0907441
Reverse Controller Toureg – 7L6907441B (not recommended)
Reverse Controller Holder – 5N0909537A
Camera – 5N0980551A
Cable for Camera 3M – 000098654A
Using VCDS/Vagcom you need to code the CAN gateway (19), the RNS510 (37 or 56), the RVC controller with 0010007 and then perform a camera calibration.
Camera mounting option – rear hatch/boot release
Integrating the camera into the rear pop up hatch release has been a project I’ve been looking into for a while, this is now made easier by the release of the MK6 Golf as this has a camera integrated into the hatch release.
Golf 6 hatch release – 5K0 827 469J
Passat CC boot release – 5K0 827 469H
Mounting gasket is the same for Golf 6, Passat CC and Golf 5. Switch for the hatch/boot release is the same as well.
Both Golf 5 and Golf 6 use the Q CANBUS gateway.
Using an aftermarket reverse camera with the RNS510
I’m currently working on this as part of another project so the information here is sketchy for the time being.
In the Radio Configuration II there is a Byte 3, Bit 6 (Backup Camera Low – without control module)