[anom3]

The best / easiest method is just to run the wire to the front of the car. Thats how I have it set up... I have a dual cam (front + rear), so as far as power goes, its just the front piece that takes power... But the idea is the same as the rear needs to be plugged into the front.

A quick rundown would be:

a) Remove passenger side rear seat. Takes a couple of strong trusts and it comes right out. I am talking about just the part that sits under your rear end when you are sitting in the rear passenger side.

b) Remove passenger side rear "side pillow". The part that sits between your right hip and right shoulder if you are sitting in the rear on the passengers side. It pops right out, top first.

c) Remove passenger side C pillar. There is a torx screw behind the "air bag" plastic piece. There is no air bag there, so don't worry. Remove the torx screw, and its held in place by 2-3 clips. To pop it out pull it towards the center of the car / top mounted center brake light. Yes, this takes quite some force. Trim removal tools help lots here. This can be a little tricky, just bare in mind the clips essentially run along the rear window. So thats where you want to pop it out first before sliding it out.

d) Remove the large trim on the passenger side front seat that's right by the door. Not the one under the door (that should read "M3"), its the one right by the seat controls. Held in place by 6-7 clips. Start from one side and slowly pop it out.

e) Remove SOME (not all) of the gasket strip that sits between the door and the car on the front passenger side. I am talking about the long "circle" gasket that seals the front passenger door to the car. Attached to the car side. You want to pull off about 0.5 meters worth between the floor of the car (essentially where your feet are if you are sitting front passenger side) to just above the fuse box. This is where the wire will be hidden right before you fish it to the fuse box.

f) At this point you have everything you need to run a cable from the junction box (fuse box) to the rear of the car and hide the cable nice and clean.

That's how I did my rear camera setup. As mentioned, mine was 1-2 more steps as I had to run the cable up to the front camera... But essentially the same.

PS : If you really really want to tap something in the rear then the easiest would be the combox (assuming you have one). Look up the pin layout for the combox and splice into the wires there. Its KL30G, so it will turn off 30 minutes after the car has been locked / left idle and turned off. The combox is located at the furthers point under the trunk "floor" when you remove it, assuming you are standing at the back looking forward in the same direction you would be traveling if you were driving forwards.