Stereos
How a Reversing Camera Is Wired Into Your Car
A reversing camera looks like a simple product. A small camera at the back, a picture at the front. The part people underestimate is everything in between: the wiring run through the length of the vehicle, the trigger signal that tells the screen to switch, and the power source that keeps the camera from draining your battery.
Here is what actually happens when a reversing camera gets wired into a car, and where installs go wrong.
The four connections every reversing camera needs
Whatever brand you fit, the wiring comes down to four jobs.
1. Camera power
The camera needs 12V. On almost every install this is taken from the reverse light circuit, because that circuit is only live when the car is in reverse. That means the camera powers up exactly when you need it and draws nothing the rest of the time.
The catch is that some modern vehicles use pulsed or CAN-controlled reverse lights rather than a simple 12V feed. On those, tapping the light directly gives you a flickering image or a camera that will not power up at all. A relay or a voltage stabiliser solves it, but you have to know to look.
2. The video signal
The camera’s video cable runs from the rear of the vehicle to the head unit or monitor at the front. That is a long run, typically along one sill under the carpet or trim, then up into the dash.
Two things matter here. The cable should not be run alongside high-current wiring, or you get interference lines across the picture. And it should never be run through a door aperture where the weather seal gets compressed against it, because that is how the cable eventually chafes through.
3. The reverse trigger
This is the wire that tells the screen to switch to camera view automatically when you select reverse. It is separate from camera power, though on many kits they share the same source.
Without it you have a camera that works only if you manually switch inputs, which nobody does under pressure while reversing out of a tight space.
4. The screen
Your camera has to display somewhere. You have three options:
- An existing factory screen. Sometimes possible, often not, depending on whether the vehicle supports an aftermarket video input.
- A new head unit with a camera input. The cleanest result, and it upgrades your stereo at the same time.
- A standalone monitor or mirror-mount display. Cheapest, but it is an extra object stuck to your dash.
Where the run actually goes
On a typical sedan or hatch the cable path is: rear bumper or number plate housing, through a grommet into the boot, along the sill under the door trim, under the carpet through the cabin, up the A-pillar or through the glovebox, into the back of the head unit.
That means removing rear trim, at least one door sill, some carpet edge, and the head unit itself. It is not difficult work, but it is fiddly work, and every trim clip you break is a clip you have to replace.
On a ute, van, or motorhome the run is longer and the rear mounting is more exposed to water and road grime, so gland sealing at the camera end matters much more.
DIY or get it fitted?
Honest answer: if you have wired accessories before, own trim removal tools, and are comfortable pulling your head unit out, you can do this. Plenty of people do.
What people underestimate is time. A first install typically takes three to five hours once you factor in figuring out the trim, running the cable properly rather than shoving it under the carpet, and diagnosing why the picture is flickering.
Get it fitted if any of these apply:
- Your vehicle has CAN bus controlled lighting
- You want the camera integrated into a factory screen
- You are fitting a new head unit at the same time
- You would rather not be the person who broke six trim clips finding out where the cable goes
The Atlia Vision range
We build our own camera range under the Atlia name, in three versions:
- Atlia Vision 1 — HD fish eye lens with night vision, front and rear capable, for a wider field of view
- Atlia Vision 2 — front and rear view camera, the general purpose option
- Atlia Vision 3 — metal body construction, the pick if the camera is going somewhere exposed
You can see the full range on our reverse cameras page.
Getting it fitted at Touchstone Automotive
We install reversing cameras at our Auckland workshop, including cable routing, trigger wiring, and integration with either a new head unit or your existing screen where the vehicle supports it. If you already have a camera, we will fit that too.
Tell us your make, model and year and what you want it displaying on, and we will come back with a quote.
