Mazda CX-3 Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
Hello, I am planning to install a hitch, 4 pin trailer harness, 4 to 7 pin adapter and proportional brake controller in my 2018 CX3 GX. My friend (who is actually doing the work) wonders whether the car wiring harness is plug and play for a controller or whether he will have to splice in a wire. Does anyone have a wiring harness diagram that would show this information?
Thanks for all suggestions and comments.
 

·
Registered
Joined
·
191 Posts
Since Mazda doesn't recommend towing with the CX3, I would expect you will need to splice wires.

I've thought about a hitch on my CX3 for a small utility trailer or hitch mounted rack, but the warning in the manual has me concerned. What kind of hitch did you find to fit the CX3?
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #3 ·
The hitch is Curt 114183 and the four pin harness is Curt 56300. Both are specified for Mazda CX3 2016-2018. I found this info on Amazon, and on Curt, and spoke with a Curt person. Likely they all have the same info, so fingers crossed that it all fits! I'm hoping to get it done next week. If you search anywhere other that North America you will see that the towing capacity is 2000lbs, and in Europe speed limits for vehicles with trailers are lower, (60mph/96kph) so I'm running with that, and driving slowly and carefully. My camper weighs about 1750 loaded, apparently. I haven't tried it yet, because no hitch!

Electric brakes on the trailer add a layer of complexity (but also safety), and I had to get a 4-7 pin adapter (Curt 57674, generic fit) and a brake controller (also generic fit), which needs to run to the car's wiring harness, and whether that is plug and play is yet to be determined, so my friend may have to splice it in.
 

·
Registered
Joined
·
50 Posts
Good afternoon Ibeez,
I installed the same configuration as you are considering except for the trailer braking system, which I cannot be of any help. The trailer hitch is a simple 1 hour job and you do not have to remove the exhaust supports. As for the wiring for the trailer lights I ran the black power wire to the interior drivers side fuse box under the door scuff trims. I attached the wire using a fusetap. This is the link for the location of the slot.You want to use the mini fusetap Fuse Tap I tow a heavy 4 by 8 trailer and have not had any problems. You might want to consider strengthening the drivers side of the hitch attachment. good luck ans if you have any questions feel free to ask.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #5 ·
Thank you for the tips! I will pass all of this on to my friend.
May I ask, how did you "strengthen the driver's side of the hitch attachment"?
 

·
Registered
Joined
·
50 Posts
You can drill a hole between the two bumper support bolts with a right angle drill and bolt it with a galvanized or stainless steel bolt/washers/nut.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #7 ·
Thank you. I am going to show all these suggestions to my friend tomorrow. I think the brake controller and 7 pin adapter will have to wait until he finds a wiring diagram for the Mazda, because as this is a somewhat unusual set-up, information is scant about connecting to the brake electricals. He is going to install the hitch and 4-pin harness, and that way I can collect the camper this weekend, with any luck. I can't wait to get it home! I will report back with the results.
 
1 - 7 of 7 Posts
Top