CX-9 OEM Trailer Hitch, wiring?

I just installed the Curt hitch and wiring harness. I don't know about the Amazon harness, but the one I bought plugged in on the passenger side of the car, on the side of the trunk compartment. It's pretty easy to do, just takes about 30 minutes. For the record I don't have the towing package, from what I read all current CX-9's have the wiring in the car, mine did and it plugged right in.

This link is to a youtube video of the install. https://www.youtube.com/watch?v=DdHgr0-P6vU

Not sure if this applies to the pre-2016 model though.
 
Did you install it like they did in the video with the wiring coming out the rear hatch? While it may work, there has got to be a better way than that.
 
Did you install it like they did in the video with the wiring coming out the rear hatch? While it may work, there has got to be a better way than that.
I did install it like that, and yes there's a better way but I chose not to go there this time. I also installed the same hitch and wiring harness in my wife's CX-5 and ran the wiring through a grommet in the trunk floor. It's cleaner, but the wiring is always exposed to the elements (not really a big deal here in SoCal). I figured I'd try it their way this time and see which lasts longer.

Another option would be to run the wiring under the trunk sill cover, inside the bumper cover down to the hitch. This would be very clean, but I don't think the wiring provided is long enough to snake through this route.
 
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I called the dealer parts department to ask if mine was set up for the wiring. I gave him th eVIN and he looked it up. Said no its not set up for the wiring. So I will get the CURT wiring.

I trying to decide if the Draw Tite hitch is worth the $30 more than the Curt. I don't know why Curt has that plate welded on top.
 
I just installed the Curt hitch and wiring harness. I don't know about the Amazon harness, but the one I bought plugged in on the passenger side of the car, on the side of the trunk compartment. It's pretty easy to do, just takes about 30 minutes. For the record I don't have the towing package, from what I read all current CX-9's have the wiring in the car, mine did and it plugged right in.

This link is to a youtube video of the install. https://www.youtube.com/watch?v=DdHgr0-P6vU

Not sure if this applies to the pre-2016 model though.

In the US, there is no indication about a tow package option, but your saying that your car has the towing package connection in the rear?

I've been trying to find out a way to know if we have that tow package or not without taking apart the rear panels.

Im also trying to figure out how this affects the solution to getting a 7 pin connection as well.

I recently found out that the airstream Basecamp rv trailer is only 2500lbs, and thought it'd be fun to rent one for a weekend, but it requires a 7 pin connection.
 
The factory wiring is for a 4-pin trailer connector. tail lights, left signal, right signal, negative.

7-pin connectors will use these, plus you'll have to run wiring from your electric trailer brake controller to the connector (and power to the controller), #10 power wire for battery charging (cabin battery as well as break-away brake power), auxiliary line sometimes unused, sometimes for back up lights. For reliability with trailer brakes I never use twist connectors and don't like crimp connectors. Solder & shrink tube are the most reliable. I run a #12 negative wire from the brakes to the connector and from the connector to the negative battery post, not bonded through the chassis. Reliability is everything with brakes.
 
In the US, there is no indication about a tow package option, but you're saying that your car has the towing package connection in the rear?
That's correct. The connection was behind the panel on my car and I did not specifically purchase a tow package.

I've been trying to find out a way to know if we have that tow package or not without taking apart the rear panels.
Taking off the panels is actually pretty easy, but as far as I'm aware, the only way to know is to peek back there.

Im also trying to figure out how this affects the solution to getting a 7 pin connection as well.
I think PTguy can answer that better than me, good luck!
 
I'm ready to get the wiring now that I've got the hitch installed. I see the T-One harness from eTrailer is $47 and OEM is $48 on MazdaSwag. Any reason to get one vs the other?
 
etrailer sold me a 2" CURT hitch for my 2016 CX9. It arrived with the powder coating chipped (just FYI they won't discount for shipping damage) anyway, they have a great tutorial video on their site that walks you through it. You need to loosen and lower but don't need to remove the muffler ass'y. The plastic filler panel comes of permanently. I was able to do the job solo using jackstands and the hitch fits nice and tight under the bumper. Wiring the wiring for the trailer connector was easy enough, but you do have to remove both taillights and run the power wire all the way up to the battery (under the shielding under the car) Will post photos later if I remember.
 
I called the dealer parts department to ask if mine was set up for the wiring. I gave him th eVIN and he looked it up. Said no its not set up for the wiring. So I will get the CURT wiring.

I did exactly the same and was told the same from the dealer - that there was no wiring behind the panel.

I trying to decide if the Draw Tite hitch is worth the $30 more than the Curt. I don't know why Curt has that plate welded on top.
 
Did you install it like they did in the video with the wiring coming out the rear hatch? While it may work, there has got to be a better way than that.

you can drop the wire down the left side taillight cavity and pop it out under the car with no modifications to the car - then just zip tie it along until you reach the hitch center.
 
On our 2018 the Mazda wiring was plug and play. And well worth it. No running wires up front or taking out the tail lights. Just removing most of the back interior.
 
I did install it like that, and yes there's a better way but I chose not to go there this time. I also installed the same hitch and wiring harness in my wife's CX-5 and ran the wiring through a grommet in the trunk floor. It's cleaner, but the wiring is always exposed to the elements (not really a big deal here in SoCal). I figured I'd try it their way this time and see which lasts longer.

Another option would be to run the wiring under the trunk sill cover, inside the bumper cover down to the hitch. This would be very clean, but I don't think the wiring provided is long enough to snake through this route.
For the record I did end up going back and revising the wiring. I spliced in a section of wire to make it longer and then ran it across the trunk (underneath the mats) and through a grommet in the trunk floor, then back over to the hitch. I then secured it to the hitch with zip ties. Much easier to access the wiring now, but it did take about 30 minutes of work to soldier /heat shrink everything.
 
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