While the headliner is pulled down, I decided to install the microphone for the Alpine KCE-300BT BlueTooth module. I removed the OEM microphone and put it in the same location:



The mic cable was also run down the A-pillar and into the center console. The BlueTooth module itself was installed inside the storage box:



Finally in the headliner, is the question of that OEM backup camera. Not sure what I was expecting, but I didn't see anything that looked like it would be connected to a camera. A quick drive over to the dealership proved that it was indeed this little connecter towards the front:



...but again, this is not what you would expect video on. There was four wires taped together as per the schematic:



To be safe, I pulled the tailgate apart and checked for continuity on the wires:



Sure enough, these are the right wires. So I spliced a sheilded cable to the video feed (red V+, grey V-) and a red/black cable for the camera power (black B+, white GND):



From the factory harness:

Black = 12v (CA+) <-- accessory power must be brought to here
White = Ground (CGND) <-- ground must be brought to here
Red = Center of coax (V+)
Grey = Shield of coax (V-)

Again, these were fished down the A-pillar and over to the center console.

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