I got a new (to me – it was my mum’s!) car back in 2022, for baby hauling. Cars came a long way in the 12 years since it was made, so I added the following to it:
- 1 – Front and rear dashcam
- 2 – Head unit with car play
- 3 – Front and rear sensors
- 4 – Reversing Camera
Item 2 required item 4, and since I was going to be pulling large portions of it apart anyway, I figured may as well do all of the above..
Reversing cameras require power to run the camera, and that is also sent to the head unit to know when to show the camera, so I needed a feed from the reversing lights to go to the camera and to the head unit. I had installed the sensors back in 2022, but the wire joiners I used were crap, so I didn’t want to do that again, and the wire from the tail lights I hooked into was inconvenient to get to. So a friend suggested using the trailer hookup. I found that, but the documentation on exactly which wire does which isn’t super easy to find – each of the circuits is documented seperately in Subaru’s documentation, so you can’t just say “what is the pinout of connector R79?”
So here it is:
R79
- 10 – Blue – FB-1 F/B FUSE NO. 1 (BAT)
- 9 – Brown/Yellow – Reversing Light
- 8 – Black/Yellow – GND
- 7 – Black/Yellow – GND
- 6 – Red – Rear fog light
- 5 – Blue/Black – Turning – Right
- 4 – Light green – Turning – Left
- 3 – Brown – Brake
- 2 – Pink – License Plate Light
- 1 – N/C – N/C
So for the camera, pretty obviously you want Brown/Yellow and Black/Yellow. Run a wire from the front to back and also to the camera. Simples, right? Well, once you fish it and the video cable and the dashcam USB cable through the tiny tube to the liftback, sure.. The first camera I got was a piece of poop, so I got a second one which is much better – I recommend this one – https://www.aliexpress.com/item/1005005764743719.html
The more complex question was for the reversing sensors – they require 12V, Brake, Reverse and Negative. You wouldn’t want to use pin 10, as that is live all the time and will drain your battery, so I hooked mine up to 6 – Red – this means the reversing sensors shouldn’t work unless you have your lights on.. except I found they did anyway, so it must also work without it. Your mileage may vary.
Hope this helps someone one day!