Hitch Wiring Harness for 2012 CX9 Sport

jweaks

Contributor
:
Mazda CX-9 Sport 2012 & Mazda3 2018 Touring
I put a Curt hitch on my 2012 CX9 Sport and works great for my bike rack the last 2 years.
I just bought the OEM Mazda Wiring Harness, for light trailer use (I'm aware of the 2k limit) hoping that the plug-n-play connector would work, however pulled panels and saw no connector, then came back to the forums and concluded that only the Grand Touring and some Tourings have it.

So, suggestions for best way to get a harness hooked up on for my hitch?
1. Take the OEM harness to dealer and ask them to install?
2. Get a third party place to do an install?
3. Reference to CLEAR directions for using the OEM harness, but splicing into the blinkers, brake lights and getting power, etc., for a diy.

Thanks for any advice/help.
 
That looks awesome. Thanks so much. I'm just a little skiddish about my ability/time to run the power cable all the way to the front.
It would also mean I'm stuck with the OEM harness.
 
I don't see why you couldn't tap into constant +12v somewhere else other than the battery. You can't return the OEM harness for a refund? if not than you could consider selling it on eBay.
 
For what it's worth when we did that Curt wiring on my friend's non Touring we tapped into the existing 'cigarette lighter' power outlet in the rear of the vehicle insted of running a wire all the way up to the battery. It has been working well for some time with that setup.
 
For what it's worth when we did that Curt wiring on my friend's non Touring we tapped into the existing 'cigarette lighter' power outlet in the rear of the vehicle insted of running a wire all the way up to the battery. It has been working well for some time with that setup.

Exactly what I was thinking if you need 12v+ source back there. Perfectly located.
 
Any assistance on how to tap into that 12v outlet that's there in the back?

I've looked at it... will I be soldering, splicing, what? Do I remove that outlet, or by tapping in can I splice off leaving the outlet functional as well?
 
Sent a quick reply to the message. However, for others you can use a 'tap' that you can purchase at any parts store. It's the type that is split and goes over the existing hot line and the one from the harness goes into a slot, pinch the tap and it makes the connection between the two....
 
Sent a quick reply to the message. However, for others you can use a 'tap' that you can purchase at any parts store. It's the type that is split and goes over the existing hot line and the one from the harness goes into a slot, pinch the tap and it makes the connection between the two....

This is what you can use. You can pick them up @ any auto parts store, I think even Wal-Mart carries them in the automotive section, they come in a few different sizes for different gauges of wires.

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Thanks so much to you both.
Anyone know the gauge of the hot wire coming into that 12v accessory outlet that I'll be tapping into?

Also, any need to still put the inline fuse in the setup, since there is already a fuse upstream from the outlet?
 
Thanks so much to you both.
Anyone know the gauge of the hot wire coming into that 12v accessory outlet that I'll be tapping into?

Also, any need to still put the inline fuse in the setup, since there is already a fuse upstream from the outlet?

My guess would be 18 gauge, the red one pictured should work for you (I think they are 18-22 gauge standard). Make sure you have a good pair of pliers too to clamp down hard on that before you flip the cover over (i.e. clamp the metal down into the wires first, it's easier and applies even pressure to make sure it's a good fit).

As for the fuse, I would say it's not a bad idea if you ever plan to use the outlet at the same time as the trailer wiring, as the load will be increased. Also a good idea to isolate a problem if the trailer lights ever stop working, you can check that fuse first.
 
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Thanks... is it the red/yellow wire going to the outlet that I tap into? (or the black one?)

It's the red/yellow one, right? That's + right? The circuit is completed cause the assembly had a ground going to the chassis?
 
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