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Hi guys.
I'm installing some things near the front of my Nb, and I need a constant 12v supply. The power cables aren't long enough to run to the 12v socket in the cabin.
I'd like it to be constant, as the items need to be on all the time.
Any suggestions would be appreciated.

On all the time or on only when the car is on?
There's a 12v (Only when car is running) feed for timing lights behind the pass. headlight, on NA's at least.

Haha, only when ignition is on/engine running.
I'm unsure if that is there on the Nb, but I can look it up.

For a constant non switched source you can use the central post in the fuse box.

Bear in mind, that's not fused so you MUST put one on your circuit.

Alternatively on the nb8a the ABS circuit is unused, so you can simply use the ABS pins in the fuse box.
It's rated for 20amp from memory.


I've got my driving lamps and compressor wired to the main post of the fuse box, via a relay.

Just noticed, you want it switched via ignition.

Both the methods I've said above are always live, regardless of the car being on or not.


If you're wanting to power anything more than a tiny device I'd be using a relay and having the ignition switched wire used only as the trigger, and using the main fuse box feed for he actual power.


What are you actually wiring in anyway?

I was actually considering using the fuse box, but wasn't aware it was always live.
Wiring daytime running lights (getting sick of people not seeing me), and a front facing camera that connects to my head unit (haven't figure out how to get the cables to there yet...).

Could also run a fuse tap from the fusebox in the interior through a grommet on the firewall to the engine bay. Through the same fuse for your hazards.

Fuse taps are gems.

All great info, thanks heaps for chipping in.
Thanks all for the info. A great help

Tigger wrote:I was actually considering using the fuse box, but wasn't aware it was always live.
Wiring daytime running lights (getting sick of people not seeing me), and a front facing camera that connects to my head unit (haven't figure out how to get the cables to there yet...).

On an NB, don't bother with daytime running lights, just turn your headlights on when driving, there's no penalty doing this like there is for NAs (ie. added wind resistance).

That's what I have been doing since a few close calls. However, I want them in my fog light area. NSW law states they can't be on unless visibly is extremely low, which I find stupid.
It sounds silly, but I don't want that area to go to waste lol.

Tigger wrote:I was actually considering using the fuse box, but wasn't aware it was always live.
Wiring daytime running lights (getting sick of people not seeing me), and a front facing camera that connects to my head unit (haven't figure out how to get the cables to there yet...).

Drl you're best to use a relay, not sure how much current hey draw, but a relay guarantees safety (of course, use a fuse as well)


As far as the camera goes, that's best mounted inside the car anyway, to avoid having the lens damages by stones/dirt etc.
For running the cables, simply run them around the windscreen pressed behind the plastic panels.
Then run behind the glove box and down to the cig lighter (either hard wire, or run the plug out to the socket)

Thanks for the tip, that'll make things nice and tidy.
Fuse and relay will definitely be the way to go.

Tigger wrote:That's what I have been doing since a few close calls. However, I want them in my fog light area. NSW law states they can't be on unless visibly is extremely low, which I find stupid.
It sounds silly, but I don't want that area to go to waste lol.

The foglights are very low so will unlikely be seen by others unless you're a long way away - this defeats your intent.

If you want to make use of the foglights, use them as vents for brake ducts, oil cooler ducts, or CAI ducts.

I'm just trying to save you time/money/effort by suggesting don't bother.

if you are wiring daytime running lamps and they are proper units you can pick up power from the starter motor. You dont need to remove fog lights - appropriate units e.g. Philips Daylight 4 will fit in the grille opening. The Philips units have proper switching and wiring provided. Its not a good idea to run headlights either --- the idea for DRLS is pretty obvious and now virtually standard on most cars.

DRLs? Headlights on low beam FTW

If you really must go for the second best solution, WIRE THEM TO GO OFF WHEN THE HEADLIGHTS COME ON. There are far too many fwits driving around at night with DRLs/'foglights' on, please don't be that person.