Trying to save some money...

This http://www.courtesyparts.com/relay-poll-p-305795.html States that its for 2006+ models so I'm assuming my 2005 doesn't need an additional relay?

And as for this harness http://www.courtesyparts.com/nissan-wir ... -9486.html Do I NEED it or can I cut the factory connector off from under the dash and just wire it directly to the controller wires with some butt-splices?

Instead of using the harness suggested here http://www.courtesyparts.com/receiver-h ... Path=6833& I'm going to attempt to cut the connector off a 7-way from a 2008 Toyota Tacoma that I have and use it, they all have universal wiring anyway so It should be easy to tap into the 4 Flat and splice into the 7-Way. I'll have to run additional wires I'm sure for battery(+), Electric Brake, and Backup Lamps

Am I right in thinking I do not have to buy any of the stuff from the original post if I just splice and run the needed wires?

This is my harness connected to my existing 4-Flat Plug:

At the grey connector the wires change colors, and there is an extra yellow wire heading somewhere back to the vehicle...
This is basically how the wiring goes through the grey connector:

Black to White (GROUND)
Green to Green (Turn/Stop Right)
Purple to Yellow (Turn/Stop Left)
Red to Brown (Tail Lamp)
Yellow to "BLANK" (????)
"BLANK" to "BLANK"
Anyone know what the mystery YELLOW is?

I also have this blanked off connector back there:

It has 1 Purple Wire and 1 Brown wire, What are they for????

And finally under my dash I have this connector:

It has 1 orange, 1 red, 1 brown, 1 black, and 1 white wire, I assume it's my brake controller harness
This is a rough layout of the wires/colors as seen from the connector face


Can anyone tell me what wire goes to what? anyone with a Nissan harness that can tell me what color wires match up with mine?
If I had a clear picture of the nissan harness wires or a rough layout like i made I could use these instructions: "1) Open the front drivers door. Slide the driver's seat rearward as far as possible.
2) Push the parking brake underneath the cockpit to make room.
3) From underneath the cockpit, find the Wiring Harness connector taped to a wiring harness.
4) Peel off the tape and connect the Wiring Harness cable.
5) Wire color designation for electric brake Wiring Harness:
WIRE COLOR:
RED/GREEN - Vehicle stop lamp switch to trailer brake connector
Black - Brake connector ground
BROWN/WHITE - Trailer brake controller switch output
RED/BLUE - Trailer brake controller illumination
RED - Fused trailer brake controller battery feed (B+)"

My new 7-way has 4 wires that will tap into the existing Flat-4 socket
and 3 wires that I'm not sure where to tie-in/connect/run to, perhaps the yellow mystery wire in the grey connector or the brown or purple wire in the black connector?:

BLACK - Battery (+) 12v <-- do i just run this straight to the battery or can i tap in somewhere

BLUE - Electric Brake <-- I assume this goes to the controller, but is there a wire I can already tap into?

Yellow- Back-Up Lamp <-- where do I take this one?

bump?

I have a reese brake controller. The controller has the following colors...Red, White, Blue, Black. They look like this...
X O
XXOX
Coming from the brake controller...
Top left is Red. It matches with the green from the vehicle.
Bottom left is White. It matches with black from the vehicle.
Next to White, is Blue. It matches with Brown from the vehicle.
The O is blank.
Bottom right is Black. It matches with Orange from the vehicle.
Top right O is blank.
However coming from the vehicle is a red wire, which fits in my harness but does not have a match. Let me know if this helps.

Any update on this?

Just finished installation of 7 way towing harness and Tekonsha IQ electric brake controller. Learned a few things:

1. It was all "plug and play."
2. The Nissan rear 7 pin towing cable plugs into and replaces the 4 pin cable, with the exception that you remove the plug on the brake connector an snap in.
3. You must purchase and snap in a "towing relay" in engine compartment that makes trailer lights work. Nissan part 25230-7996A, $38. Or Auto Zone part "Duralast Relay" 20228 for $18. I used the Auto Zone.
4. The Nissan dealer's ebrake controller harness did not come with a plug for the Tekonsha. I bought a Tekonsha cable. And will return Nissan's back.
5. The ebrake controller snapped into a matching plug above the gas pedal behind the dash. It was zip tied to other wires and not in any kind of electrical box.
6. Installed a sway bar on weight distribution hitch.

http://airstreamdiary.blogspot.com/2011 ... rness.html

Towing 18' travel trailer GVW and hitch weight below vehicle limit.