2007~2015 CX-9 Trailer brake controller installation?

Hello, I need help installing my brake controller and converting my 4 pin to a 7 pin. Has anybody done this and have pictures for guidance? I can't seem to find a T harness adapter for Tekonsha p2, the best routes to run wiring and the best way to install the controller. I own a 2013 Mazda CX9 AWD that did NOT have the factory Tow hitch installed.

I was told there is pre wiring for the brake controller bit I can't find any domineering on it. Also, I already have a 4 way plug installed

Also, if anyone has tips, tricks and pre trip prep (fluid or fuel optimizer recommendations) that would be awesome, I'm about to travel from Kansas to Virginia hauling a Aurora light by forest river.
 
You cannot convert a 4-pin to a 7-pin. You could do the reverse if you had a 7-pin connection on the car and towing a trailer with 4-pin wiring. From your 4-pin you can reuse the brake light & turn signal and tail light wiring. You need to add a 12v charge wire, larger capacity negative wire, and brake actuating wiring, and probably won't use a back up light.

What is the tow rating of your car? What is your state law requiring trailer brakes? What is the fully loaded weight of that trailer?

I've never seen prewiring for a brake controller. Anyway, go to etrailer.com for the best set up for your car.

I strongly recommend a proportional brake controller. I strongly recommend running the negative wire from the trailer through the 7-pin plug direct to the battery negative terminal with a #10 or 12 wire. Nothing is more important here than reliable trailer brakes, and you need the most reliable connections. Do not use wire nuts; do not ground the negative through the car body. You will need a 40 amp circuit breaker and #10 wire for the charge wiring from the battery positive post to the 7-pin plug.
 
Just curious, what is the towing capacity of a CX-9? I wouldn't think it was high enough to pull a trailer that required brakes.
 
In the US, the first gen is rated at 3500 pounds with the tow package and 2000 without it.

Overseas, it's rated differently (higher, I think).
 
Be mindful that tow ratings are total weight. Including the weight of the trailer and any cargo you're hauling, the cargo in the hatch, and even *you*.
 
I had a very successful trip with my 2013 Mazda CX9 AWD. We drove from Kansas to Virginia with absolutely no issues.
Setting the power depending on the topography.
Not using cruise control to avoid the shifting issues discussed in this forum.
Focus on weight distribution and keep it light. This will make or break your trip!

If you aren't sure about your weight go to the local dump and roll over the scales with your rv empty and record the weight then, once you load your RV, roll back over the scales and subtract the difference. - That's your load weight. Take into consideration, your own weight as well as any passengers, cargo, fuel, hitch assembly (sway bar, ect)
Follow your guidelines on load limits to keep it close to 3500 or less. This is the trailer weight plus any additional cargo. (In the trailer and the vehicle)

Installed hardware:
Tekonsha P2 brake controller
Blue Ox Sway Controller (a life saver and required, in my opinion)
Forrest River Aurora Lite (2,969 lbs)
 
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There are different weight maximums that must be observed.
  • Max trailer weight is the total weight of the loaded trailer alone...batteries, propane, water, groceries, bikes, etc.
  • Gross combined weight rating GCWR is the max limit of the total weight of everything from the front bumper of the tow vehicle to the tail lights of the trailer...tow vehicle, people, luggage, boats on top, hitch, trailer, trailer's full contents. GCWR can be hard to find for some vehicles.
  • Gross Vehicle Weight Rating GVWR is the tow vehicle max allowable weight including driver & passengers, luggage, full tank, and the weight of the hitch and trailer's tongue weight. The tow vehicle will also have maximum axle weight ratings for the front and rear ends.
  • Trailer brake requirement is either specified by tow vehicle brake ability or state regulations. My state requires trailer brakes on trailers over 3,000 pounds of actual weight, but some tow vehicles requires trailer brakes on trailers lower than that weight. (I'm not sure what happens when one tows into a state with with lower limits...probably it doesn't get checked unless you crash.)
All weight limits must be observed, and preferably give yourself some margin by coming in under the limits.

There are several very good proportional trailer brake controllers on the market. Horizon's Prodigy P2 or P3 are excellent and sold under several brand names including Tekonsha, Reese, and Draw-tite. These proportional controllers detect the rate the vehicle is slowing and apply the trailer brakes proportionally. Avoid the timed controllers. It makes no sense to have the trailer brakes increase braking depending on how long your foot is on the brake pedal.

There are several weight distributing trailer hitches with built in sway damping. All work much better than the old friction sway damper bar. Blue Ox is one good one. Equal-i-zer and Curt are also good. Weight distributing hitches work to lift the tow vehicle's back end to level it so the trailer tongue weight is evenly distributed both ends of the tow vehicle. This gives much better, safer handling of the tow. The weight distributing spring bar rating needs to be matched to the trailer tongue weight.

When we had a travel trailer I went through a couple of unsatisfactory types of sway damping hitches then settled on a Hensley Arrow sway elimination hitch. Expensive and worth every penny when gusting side winds blew and my rig stayed arrow straight down the road. The ProPride 3P hitch might be a modern update of the Hensley Arrow hitch. (The Equal-i-zer would have been my budget back up better-than-most sway damping hitch.)
 
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