09 CX9 GT AWD trailer wiring ???

[kmmon1]

I installed a class 3 hidden hitch and also purcahsed the quick connect wiring harness that is plug and play to the stock tailights.. I have done these wiring before and has been simple, just plug into the taillight wiring harness and done. For some reason the CX9 kit states I need to run a Power wire all the way to the battery.... I have never seen this before.
My question is:
The 09 GT is from the factory set for the trailer kit, It is not an option. (Only option is the hitch and wiring) Is there a power wire already in the rear of this car so I do not need to run the wire all the way to the battery?? maybe pre wired from the factory so dealers or the factory do not have to run this wire.

Thanks
Kevin

[kmmon1]

I will try to see if it is pre wired, if not did you run it under car or through interior?

[ceric]

I have read an aftermarket T-connector instruction on eBay (made by Curt). The instruction also included running a wire from battery.
My guess is that all the tap point at the rear hatch area cannot supply enough current to drive several stop lights (75W - 3 stop lights, 25W each + 2 tail lights 10W each - together you are looking at nearly 100W - that is 100W/13V = 8A!).
It is probably safer to run its own power from the battery.
Again, my theory only.

[kmmon1]

I went to install my quick connect kit today and found an empty connector underneith the passenger side rear. The 09 GT AWD is pre wired for a trailer light connector. I will be selling the New quick connect i just bought because I dont want to run the power wire all the way up front, the connector in the back has no constant power or I would have just wired to that and been done. I tested the connector there are 6 wires, 2 blinkers, 1 brake, 1 driving lights, and I assume 1 ground and not sure of the other 1. I will be buying the generic 4 pole wire with converter and splicing right into that connector. I wish I knew before i paid $50 for the T-one connector. I am not sure what the other models and years have.

[ceric]

Tow prep is standard on 09 AWD.
Here is the news release at that time.

....
New or enhanced for 2009:

* Trip computer standard on all models
* Bluetooth phone capability added to Sport model
* Sirius satellite radio added to Moonroof, BOSE® Audio Package and Rear Seat Entertainment System Package
* Auto-dimming rearview mirror with Homelink® added to Grand Touring model
* Heated seats and heated outside mirrors added to Sport Power Seat Package
>>> * Trailer tow preparation standard on AWD

[kmmon1]

I did not check with mazda. It is a factory style 6 pin connector female, it had separate blinkers, brake light and running lights

[brightwhite]

OK. I just bought a tent trailer and am going through the wiring disaster Mazda has created.

I have an 08 Canadian GT with towing package. This comes with the upgraded transmission cooler and all that, but no hitch and no wiring.

I bought a Reese hitch and installed it last night. I also bought the wiring harness from Mazda. This harness only hooks up to the wiring in the Mazda, but not the trailer. That wiring harness only comes if you buy the hitch from Mazda which costs twice as much as the Reese/hidden hitch model.

Anyway, the problem is that the Mazda wiring harness is a 6 wire harness:
- power
- ground
- tails
- brake lights
- left turn
- right turn

It's missing the trailer brake wiring. So, I had to buy a module from Parts for Trucks to run from power, negative, ground and brakes. This cost an additional $120.

Anyone else hook up a 7 wire system to the their CX-9? Any tips?

[brightwhite]

oh really? OK, cool. When I get in there tonight, I'll check it out. What wire did you connect to the brake connector on teh 7 plug pigtail?

[U4IA]

I bought a Reese hitch and installed it last night. I also bought the wiring harness from Mazda. This harness only hooks up to the wiring in the Mazda, but not the trailer. That wiring harness only comes if you buy the hitch from Mazda which costs twice as much as the Reese/hidden hitch model.



Hi there,

I'll be doing the same in a few weeks. But mine will be an 09 GT so it's supposed to have the pre-wiring....and I'm a bit confused too.

Doesnt that harness you bought go from the pre-wire under the passenger seat, to the hitch? I guess what you're saying is that in 08, that pre-wiring doesnt exist? (And you need the hitch to get that wiring?)

If the brake wire is included in that that harness thats a bonus - I havent seen a photo of the mazda harness to see whats involved, but theres only 6/7 wires on the hitch connector.. (http://www.marksrv.com/wiring.htm)

If you have to go from scratch, then I think what you need is one of those t-connector trailer kits that plug into the lights, and run those wires to a new 7 pin connector on the hitch...

Then, if you need a brake controller you have to run the power/ground wires from the battery through the firewall, to the brake controller.

Run the blue brake controller output to the 7-pin (once you figure out how to snake it through the vehcile)

Then, find the 12V power lead on the brake switch and attach it to the brake controller input.... I don't have the wiring for the CX-9 but I do have it for the CX-7 so hopefully its the same. (red/white wire) http://www.the12volt.com/installbay/forum_posts.asp~TID~85374

I havent taken delivery yet, but I'm hoping to just get the mazda harness and it will magically plug into the pre-wire and tada.. :)

Can anyone confirm the mazda part # on that harness, or any other insight into this? (0000-8E-M03)

[brightwhite]

I will take some pix tonight of my experience.

[brightwhite]

OK, the install of the Mazda wiring harness was trouble free for the most part. Tomorrow night, I'll be installing the brake line adapter. I found the brake wire (heavy red wire coming off the brake pedal. Now I just need to get through the firewall to connect to the Reese box.

If you have a 7 wire trailer harness you need this piece. The 4 line Mazda harness does not offer trailer brake connections from what I understand and cannot be connected to the 7 wire trailer harness.

[brightwhite]

It doesn't plug in anywhere. You have to tap 5 wires and ground the sixth. I took pix. Will post those once I get the braking adaptor installed.

[U4IA]

Has anyone else with a 09GT figured this out. We got our CX-9 today but I cant see anywhere that a wire harness connects to.

We had the dealer order the hitch cable ($120?) but I'm still not seeing anything under the rear passenger seat to connect it to....

The dealer wasnt too sure about this either..argh.

[brightwhite]

OK, I posted a set to my Flickr account. I still need to get some shots of the completed wiring, but this should give you a good idea of where it's going.

http://www.flickr.com/photos/jeffandsam/sets/72157619136141070/

[brightwhite]

I thought they had a prewired plug that the harness plugged into. That's the same thing I did, minus the additional brake control.

They do. But, you have to buy the Mazda hitch which costs $200 more than the Reese one I bought and it's not as strong. The wiring harness only comes with that (in Canada anyway).

Plus, it's not wired for a 7 prong, only a 4, and therefore doesn't have trailer brakes or a direct link to the battery which you'd need to do anyway.

[brightwhite]

It wires directly into the white Mazda connector you can see in my hand. It's then got a splitter/joiner for the brake lights and turn signals. I bought a Modulite and used that instead.

All told, wiring the trailer hitch setup cost me:
- $220 for Reese hitch
- $25 for Mazda harness
- $65 for Modulite brake/turn adapter
- $12 for 2 inline fuse holders
- $50 for wire/connectors
- $120 for Reese braking module
- $15 for 7 prong trailer plug adapter

So, about $500 or so and a few skinned knuckles. :)

Pretty happy with how it came out though.

[vikefan7]

So how much did you really save by doing it all yourself? Sounds like a lot to me, but I've only had to put a hidden hitch in and never got around to adding the connectors for the trailer. Are you going to get the transmission cooler as well?

[brightwhite]

So they sell the pigtailed connector that has to be tapped, THEN the harness to the socket plugs into that.

And you have to buy the hitch with the harness?

Exactly. Total rip off. Especially since the Mazda hitch is only a Class 2, and the aftermarket hitches I found were all Class 3. Not really a big deal since even Class 2 can do the 3500lbs, but still.

I saved about $500 in total over getting Mazda to do the install using Mazda parts.

My dealer quoted me $800 to install the complete package, which did NOT include the brake adapter and would have left me with a 4 flat wiring harness, not the 7 pin round harness I needed.So after getting them to do it, I'd still have required the brake package and a 7 pin adapter and have needed to still run wires through the firewall which was a total pain in the ass.

I'll try to snag a few pix of the completed setup in the next few days. I'm pretty proud of how it all turned out.

[brightwhite]

Are you going to get the transmission cooler as well?

My GT has the cooler already. All 2008 AWD CX-9s sold in Canada have the towing package, but no hitch or wiring.

I towed the 2,900 lb trailer for 3 hours on Sunday from where I bought it and the CX-9 barely broke a sweat. It was pretty awesome.

[U4IA]

Just for information, I pulled out the entire back storage compartment on my 09 CX-9 and the pre-wire cable is taped against another wiring harness on the right hand side kinda below the tail light..

So whats the part # of the pigtail mazda connection in your picture? Its exactly what I need but I've phoned a few dealers and they can't find it...?

[vikefan7]

Wow, that's ridiculous. I can't believe it's that much to have that installed by the dealer. Hopefully someone is able to find the trans cooler for you CX9SportOwner....

[U4IA]

No, its a 6 pin square connector, I'm pretty sure it connects to the harness in that picture that brightwhite is holding...

The outputs all seem to be correct though - I tested with a multi meter and checked brake ,turn signals and running lights... I'll get some pics this weekend hopefully if I get the correct cable..

I had the dealer order a 'cable' they thought was the right one, they're paying for it but its over $100 and I don't think its the right one. I'll pick it up later this week and see.. maybe you cant order the $30 cable withought the entire factory hitch still?

I'm totally amazed at how little the dealers know about some of this stuff with the cx-9....

[brightwhite]

Added more photos to my Flickr set that show Reese brake module, Modulite wiring harness, battery wiring and final hitch install.

Starts here:

http://www.flickr.com/photos/jeffandsam/3592831679/in/set-72157619136141070/

vikefan7, you're right, it's way too much. I enjoyed the process, but was surprised by how many 'extras' I needed.

CX9-Sport, the 6 wires map as follows: 12v aux, ground, left turn, right turn, brakes and running lights. No trailer brakes and you still need the other module to convert your turn and brake signals to a single input. That's what that extra Mazda harness or the Modulite does for you.

[brightwhite]

Oooo, good call. Still need to run it through that damn grommet in the fire wall. What a pain that was!

[U4IA]

Oooo, good call. Still need to run it through that damn grommet in the fire wall. What a pain that was!

I got some pics I'll post soon... that part was pretty easy I thought...

Just pull out the battery - on that huge firewall grommet is a little nub that sticks out on the top left... poke a hole with something sharp - I used a dental pick. Spray a bit of silicon spray on it, and feed your wires through...

I guess I wasnt thinking about the brake/turn signals coming out as seperate wires... What was the advantage to the drawtite box vs the factory harness?

I was going to take out the coin holder - how hard did you have to force it to pop out? (Or is there a trick)

Thats not the part number the dealer ordered me regardless.. so not sure what I'm gonna get. (headshake

[brightwhite]

Yeah that's where I ran mine too. Still was a pain.

The advantage of the drawtite module was that you can't get the Mazda one without buying their hitch. They cone together.

Coin holder just pops out.



Just pull out the battery - on that huge firewall grommet is a little nub that sticks out on the top left... poke a hole with something sharp - I used a dental pick. Spray a bit of silicon spray on it, and feed your wires through...

I guess I wasnt thinking about the brake/turn signals coming out as seperate wires... What was the advantage to the drawtite box vs the factory harness?

I was going to take out the coin holder - how hard did you have to force it to pop out?

[brightwhite]

Nah, it's an engine, I don't care how it looks. ;) I barely wash the outside of my cars at all anymore. Too many more important things to do.

[U4IA]

Yeah that's where I ran mine too. Still was a pain.

The advantage of the drawtite module was that you can't get the Mazda one without buying their hitch. They cone together.

Coin holder just pops out.

Hmmm, ok i'm slow (lol) but what you're saying is that even if I have that pigtail connector from Mazda that connects to my pre-wiring, I still need some 'box' (mazda or drawtite) to combine the left/right and brake signals?

I just googled and it does appear there are a few little boxes that do this...

ie. http://www.expeditionportal.com/forum/showthread.php?p=365269

[brightwhite]

I'm not sure what's available for the 09s, as you have that box pre-wired in and maybe your dealer can get the proper adaptor.

Keep in mind that LED taillights require a more powerful adapter with higher power output/input. The Modulite Lite is the least expensive one I found.

[U4IA]

So I was going to post that I had this all figured out, but I got the harness from mazda and went to install it today...

Was a little confused when I tried to plug it in and realized that the vehicle pre-wire is a 6 pin female, and the mazda harness is a 6 pin female as well.

It has the mazda black box which has a flat-4 pin on one side, and the 6 pin connector which I assumed plugged into the pre-wire connector...even includes that grommet which I guess replaces the existing one below the jack.. there werent any instructions in the box, just some a troubleshooting flowchart.

So either this connector is for a 07-08 cx-9, or theres yet another connector you need.. I can always cut the end off and wire it up accordingly but that seemed to defeat the purpose of the pre-wiring...

[brightwhite]

I just bought some female blade connectors and hooked them into the male unit I had. You could like do the same with male connectors and a few inches of wire and save yourself some soldering.

[U4IA]

Yes, I'm just going to make some jumpers between the two...

Now, I found something interesting. The mazda harness I have includes the black box which is identical to the modulite. It needs 12V power to run the lights...

On the factory pre-wire connector theres a pin that didnt do anything. So I noticed theres a fuse missing that says 12V Trailer in the glove box.

So i put a 15amp fuse in, and now I get a solid 12V back there....

I'll just run the black box converter off that 12V and hopefully thats enought power. Its on a 15 amp fuse so it should be..

I just wish the dealer actually knew what i was asking as this is the cable they said would be correct, but it doesnt actually connect...(boom02) (the date on this cable says 07 so its obviously for a 07-08 non pre-wire)

Kinda wondering what the actual 09 trailer kit includes...

[brightwhite]

yeah, that sounds just like what I should have been able to buy if it wasn't only available with the hitch up here.

Interesting about the fuse. Since mine wasn't prewired in, I wonder if I have that fuse and where it grabs 12v from? The harness I have wired off the power adaptor on the right side of the trunk, so I ran a 20a fuse right off the battery instead.

[U4IA]

Question for those that installed a brake controller, I could swear someone said the brake sense wire was red/white, but that wire is 12V hot, and 0 when brake depressed...

I'm pretty sure it's the green/yellow which is 0V and then 12V when the brake is depressed.. (cold side of stop switch)

[brightwhite]

With the Reese box I put in, there was a solid red wire that looked out of place. I'm pretty sure it was wired in from my remote start, so that's what I tapped. I'm not sure what colour wire it led to.

Saying that though, this wire does get 12v when the brake is depressed and nothing when the pedal is in the normal position.

[brightwhite]

Is the brake controller a positive or negative input?

Not exactly sure what you mean, but mine has both positive and negative inputs direct from the battery. No chassis ground wire.

4 wires total:
+ 12v (white)
negative (black)
brake tap (red)
brake out to trailer (blue)

[U4IA]

It's a tekonsha P3... According to the instructions - 'STOPLIGHT SWITCH - CONNECT TO COLD SIDE (VOLTAGE ONLY WHEN PEDAL IS PUSHED)'

I didnt see any red wires hanging out.... but regardless I wired it up to the green/yelllow wire off the switch...

I'd have this done by now but two little ones keep consuming all my free time :)

[kmmon1]

I completed my install without a brake contoller, I hooked up the trailer and everything is fine. I bought the universal wiring kit with the Black box, I cut the ends and put on the flat prong connectors and plugged them right into the mazda connector, I only used the running lights, left blink, right blink, and brakes. In the factory connector they are all separate. I am still not sure what the others are for someone said 12v aux, But i never got power out of the other 2.
Very simple to do, Cost about $20 for the wiring kit, from any auto parts store. And a simple test light completes the job.
I dont need the brake controller so did not look into it...

[cbmel]

Added more photos to my Flickr set that show Reese brake module, Modulite wiring harness, battery wiring and final hitch install.

If I'm seeing the pictures correctly, you pulled the 12V for the Modulite from the power tap on the passenger rear panel. Isn't that powered only when the key is "on"?

[brightwhite]

If I'm seeing the pictures correctly, you pulled the 12V for the Modulite from the power tap on the passenger rear panel. Isn't that powered only when the key is "on"?

No, that gets a constant signal, but I'm running a wire all the way from the battery to the Modulite and into the trailer 12v. The 12v from the lighter plug is going to the accessory wire on the trailer connector.

[cbmel]

No, that gets a constant signal, but I'm running a wire all the way from the battery to the Modulite and into the trailer 12v. The 12v from the lighter plug is going to the accessory wire on the trailer connector.
Can you tell me specifically the route that you took to run the wire to the battery? I get to try doing an install tomorrow, assuming UPS ever gets here.

[brightwhite]

What CX-9 Sport said.

Also, the accessory wire is used on the 7 pin connector. Presumably to power things like interior lights etc. On the 7 pin you have the following:

- Power
- Ground
- Left turn/Brake
- Right turn/brake
- Tail lights
- Trailer Brakes
- 12v accessory

[cbmel]

No, that gets a constant signal, but I'm running a wire all the way from the battery to the Modulite and into the trailer 12v. The 12v from the lighter plug is going to the accessory wire on the trailer connector.

You're right - although the front one is switched, the back one is hot. Given that the modulite that just arrived via UPS only has a 10 amp fuse, what would be the problem with pulling the power from there, rather than running the wire all the way to the battery?

[brightwhite]

You're right - although the front one is switched, the back one is hot. Given that the modulite that just arrived via UPS only has a 10 amp fuse, what would be the problem with pulling the power from there, rather than running the wire all the way to the battery?

I considered it to save effort, but in the end I went all the way to the battery. It just gives you a cleaner signal with nothing else on the wire and you have the chance to run a heavier gauge wire too. I'm not sure if there's anything else on that circuit, but it's only running 16 or 18 gauge wire and the Modulite wants 12 or bigger.

[U4IA]

I ended up tapping into the existing pre-wire harness for the 12V for the mazda 'box'. It looks like a modulite and is probably similar.. I did notice the wire guage is a bit small, but there shouldnt be that many amps going through it. We're only powering a tent trailer lights!

I kinda assumed that had I actuallly gotten the correct factory mazda box it would plug in there anyways so should be safe... we did test the wiring and it seems ok... I guess if we have issues I'll know where to look first.

As for running power for the brake and charge line I ran them under the drivers kick panel, down under the door sill, and then back under the passenger sill and under the hard molded carpet between the 3rd row and the body..