Curt Plug-and-Play No-Splice Trailer Wiring Harness Out For Bronco

[BudgetBronco]

The Curt guide says the same:
If using the converter as a powered module for a two-wire system, the red brake wire must be grounded

There was a little delay between letting off the brake pedal and the lights going off so maybe grounding the red wire would fix that. I'll experiment with that when I permanently install the box after I find a good 12V circuit to use.

Please do let us know! I am also curious what you use for grounding point, or drill a new one. I tested the bolt right below the driver side tail light connectors for continuity to ground and it was grounded so I was thinking of using that since it would be convenient and no drilling needed

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[VoltageDrop]

Please do let us know! I am also curious what you use for grounding point, or drill a new one. I tested the bolt right below the driver side tail light connectors for continuity to ground and it was grounded so I was thinking of using that since it would be convenient and no drilling needed

As luck would have it, I think I just answered that question. I'm happy to report that even the base model (with no tow provision) does have the 3 connectors for the trailer tow module. The middle connector (C4397A) has two blue-red wires, which are 12AWG 30A and 40A circuits straight to the battery. As @flip showed in his towing thread below, Ford used the actual connector body to "cap" these connectors so all you need is the pins and you can cleanly tie into these to power the Curt box (and whatever else you might want back there). There's a nice ground stud above and forward of these connectors that I'll use for the Curt ground.

I'm still going to mount the box on the frame rail since it's set up to tie into the tail lights outside the body and it should be easy enough to run the power and ground wires through the tail light grommet and have them inside where corrosion won't be an issue as long as MIC 3.0 doesn't leak.

PS: Look at all that wasted storage space. That cavity toward the rear even goes into the base of the sport tube. I might have to cut a hole in the trim panel and put a door into that area... this 2-door needs all the nooks and crannies it can get!

Here's flip's solution, which he created using the Ford box that requires splicing. Now that there's a plug-and-play solution I wouldn't go that route but his power connector solution still applies.
https://www.bronco6g.com/forum/threads/tow-package-arrived-contents-inside.17659/page-12

 

[72BroncoSand]

The Curt guide says the same:
If using the converter as a powered module for a two-wire system, the red brake wire must be grounded

There was a little delay between letting off the brake pedal and the lights going off so maybe grounding the red wire would fix that. I'll experiment with that when I permanently install the box after I find a good 12V circuit to use.

What’s the best way to ground the “ floating red wire”?

 

[VoltageDrop]

What’s the best way to ground the “ floating red wire”?

Good question. I don't want to remove those red wires from the connectors since they help seal them so I might just cut the red wire before it forks then splice it to the white wire and run a single ground wire into the cabin.

 

[skoorb76]

As luck would have it, I think I just answered that question. I'm happy to report that even the base model (with no tow provision) does have the 3 connectors for the trailer tow module. The middle connector (C4397A) has two blue-red wires, which are 12AWG 30A and 40A circuits straight to the battery. As @flip showed in his towing thread below, Ford used the actual connector body to "cap" these connectors so all you need is the pins and you can cleanly tie into these to power the Curt box (and whatever else you might want back there). There's a nice ground stud above and forward of these connectors that I'll use for the Curt ground.

I'm still going to mount the box on the frame rail since it's set up to tie into the tail lights outside the body and it should be easy enough to run the power and ground wires through the tail light grommet and have them inside where corrosion won't be an issue as long as MIC 3.0 doesn't leak.

PS: Look at all that wasted storage space. That cavity toward the rear even goes into the base of the sport tube. I might have to cut a hole in the trim panel and put a door into that area... this 2-door needs all the nooks and crannies it can get!

Here's flip's solution, which he created using the Ford box that requires splicing. Now that there's a plug-and-play solution I wouldn't go that route but his power connector solution still applies.
https://www.bronco6g.com/forum/threads/tow-package-arrived-contents-inside.17659/page-12

Where does one get the pins? Also need to change the fuse to a 15 amp Mcase fuse to protect your wires and controller

 

[VoltageDrop]

Where does one get the pins? Also need to change the fuse to a 15 amp Mcase fuse to protect your wires and controller

I've asked flip for the part number but a 10-12 awg spade connector fits well so for now I'll likely use that and hot glue it into the connector shell.

 

[VoltageDrop]

Where does one get the pins? Also need to change the fuse to a 15 amp Mcase fuse to protect your wires and controller

I got this project wrapped up today. I used the spade connector and used electrical tape to hold it in until I get the connector pins. Grounding the red wire did fix the delay my lights had after letting off the brake pedal. I put the box on top of the frame just in front of the bumper, which allowed me to do all the splicing behind the tail light.

I used red 12 AWG for the power wire and the included black 12 AWG spliced to the box red and white wires using heat shrink 14-16 AWG butt splice connectors because I didn't have bigger ones and somehow the wire fit in there. I used split loom to cover the wires as much as possible. I couldn't figure out how to remove the tail light but that would've saved some foul language while snaking the wires through the grommet!

I was able to feed the connectors between the body and the bumper so I didn't go around the ends of the bumper like the instructions show. I zip tied the green wire along the cross member above where the hitch mounts. It all ended up fairly tidy.

 

[Lifeliberty]

So, not plug and play at all.. i can wait

 

[BlueBoy]

I recently installed the Curt hitch, plug-n-play wiring, and a 7way plug on my FE. I did the install similar to the Ford OEM in that everything is on the inside w/ cuts through each brake light grommet for the plug install. Thanks to @flip from Ruxer Ford for the initial write up and assistance with the correct pin connectors to tap into the 12v supply in the back. I used one pin for 12v to the Curt module and the second one to provide 12v supply to the 7way plug. All I am missing is the brake controller supply line (dont have yet) to power electric trailer brakes. I ran 7way wires into rear of Bronco through a rear floor grommet on the drivers side and sealed all cuts with rtv. Wrapped most all wires I added with blk cloth wire tape to prevent chafing.
Parts list:
Curt hitch #13493
Curt T-connector 5646
from Amazon.com:
Hopkins 7-way/4-way bracket 40978
Hopkins multitow 7way/4way plug 40974
Hopkins universal multitow harness connector 40985

View attachment 227552

 

[flip]

Bravo!

 

[Broncola]

Any response from Curt? I’m still a ways out from this project. Will probably run just the hitch for awhile, as I have no toys with lights yet. Swapping the pins per @VoltageDrop seems easy enough though.

I want to mount the module inside near the rear cargo power source. Not sure how feasible routing the wires and passing all the connectors through the grommets will be though.

Minor update: I called Curt today and spoke with somebody from the Product team. He asked me to send VIN, pics, description of problem, etc and said he would discuss it with the Engineering team. If I get any information from them I will share it here.

 

[BudgetBronco]

Any response from Curt? I’m still a ways out from this project. Will probably run just the hitch for awhile, as I have no toys with lights yet. Swapping the pins per @VoltageDrop seems easy enough though.

I want to mount the module inside near the rear cargo power source. Not sure how feasible routing the wires and passing all the connectors through the grommets will be though.

No meaningful reply!! Here is the email I sent on Dec 15, to which he replied to to only say that it was received and there were no questions.
"Hi Jeff, just following up to ensure you got both of my emails. Any questions from Engineering? I think you guys would want to treat this with urgency, since you are selling a product that does not work."

 

[cbrownabq]

I recently installed the Curt hitch, plug-n-play wiring, and a 7way plug on my FE. I did the install similar to the Ford OEM in that everything is on the inside w/ cuts through each brake light grommet for the plug install. Thanks to @flip from Ruxer Ford for the initial write up and assistance with the correct pin connectors to tap into the 12v supply in the back. I used one pin for 12v to the Curt module and the second one to provide 12v supply to the 7way plug. All I am missing is the brake controller supply line (dont have yet) to power electric trailer brakes. I ran 7way wires into rear of Bronco through a rear floor grommet on the drivers side and sealed all cuts with rtv. Wrapped most all wires I added with blk cloth wire tape to prevent chafing.
Parts list:
Curt hitch #13493
Curt T-connector 5646
from Amazon.com:
Hopkins 7-way/4-way bracket 40978
Hopkins multitow 7way/4way plug 40974
Hopkins universal multitow harness connector 40985

View attachment 227552

Awsome work! I will be doing this on my badlands because I need 7-pin. Have you used this and confirmed everything is working? If so, I will email my dealer and remove tow package!

 

[BlueBoy]

Awsome work! I will be doing this on my badlands because I need 7-pin. Have you used this and confirmed everything is working? If so, I will email my dealer and remove tow package!

I have used it and everything works the way it should, minus the feed from a brake controller. I haven't acquired the FORD Brake Controller Module yet because I want to research where the actual wires that feed the factory 7-way plug are located and see how feasible it is to bring the signal to the wires I have coming in from the rear floor grommet. I will update when I get it figured out.

 

[BlueBoy]

Bravo!

Good afternoon Phil, would you have access to a wiring diagram and/or info that shows the brake controller and where the signal gets routed to in the back of the Broncos? If easy enough, I will add the controller and then run the signal to the wires I have coming through the floor grommet.

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