[Monashee]

Replacing the 7-way harness on my truck. Harness is connected as per attached image.
Tested wires with my 12v test light and most are working correctly but...
I am getting a ground signal from both the Brown and White wires.
The White should be the ground and the Brown should be my tail lights.
Does this mean there is a short in the Brown (tail lights) wire?
Where would this wire be coming from? A fuse somewhere or just tapped into the truck's tail lights?
Not sure if it's the factory tow package or an aftermarket install... I do have a brake controller which is working.
Read a bunch of threads but it starts getting confusing when it comes to relays, kick panels, multiple fuse boxes, etc.

 

[Monashee]

Continued research... read a bunch more threads, the FSM (confusing!), and watched this video:

Check out the photos I took...
Missing kickpanel relays? Fuses OK. Unconnected wire at rear harness. 2 rectangular objects under hood?
Any ideas what's going on here?

 

[Monashee]

So the brown wire is splices into the truck's left tail light wire (postive wire).
With tail lights turned OFF, I get nothing out of the brown wire - correct.
With tail lights turned ON, I get a 12V reading from the brown wire - correct.
But, I'm also getting a ground reading from the brown wire (if I connect the multimeter or test light's positive terminal to the Black (12v constant) wire, or to the battery + terminal.
Tested the brown wire at both ends - at the trailer harness & at the tail light harness. Same results. No shorts or damage anywhere along the brown wire.
How can this be?!? If it's getting both a positive reading, and a grounding out, wouldn't something short out? Blow a fuse for my tail lights when I turn them on? I just don't get it.

 

[Sabretooth]

That looks like someone didn't wanna buy the trailer tow stuff from Nissan when they brought the pu and decided to do it themselves

In that second pic you have ? to wire the smaller split loom that wire looked like same color where is the wire in that going?

The forth pic is they are circuit breakers if you unscrew imprinted on top should be 10 20... 60amp

 

[Monashee]

I'm thinking I should just order the Nissan harness and do it correctly.

 

[V8 man]

Somebody did a LOT of work to avoid using the factory trailer wiring.

The boxes in the 4th picture are circuit breakers wired up for the brake controller and the charge wire on the hitch plug.
The factory tow fuses are in perfect condition because it looks like they did there best to bypass as much as possible.
Since this is a "custom" trailer wiring job, there is no off the shelf instructions on where to look for problems. It could be anywhere in the mess of wiring they added.

This is a good reason to use the factory wiring. It is a known. If something doesn't work there are published manuals on how it is wired.

I would suggest that your idea of using the factory wiring is a good idea.

 

[Monashee]

Ordered the factory wiring.