wires for trailer brake controller '24 Ranger?

[Jason B]

Is there anything stopping us from getting one of these and self-installing? I can't find the part on the major supply sites but found a few used. If the no-tow package units still have 7-pin wiring, does that mean the TRM module could plug-n-play? Other than harness compatibility, there is the question if you can even flash the unit once installed, or if it will fail to be recognized by its parent module? Haven't found any examples on here yet of someone taking this step. If not, I may take the leap to test but may need some insight from the hive mind on the flashing process, if even possible without a dealer.

I think this is the module, although I don't see any more info of what wiring is needed.
Original 2024-2025 Ford Ranger Module Trailer Brake ML3Z-19H332-R | Levittown Ford Parts

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[pezdyspensr]

So we are in the same boat it sounds. I tossed a Curt hitch on and would like to wait until I can do this right for the rest. On another thread I was told that if I have the Towing app on Sync then I must have a TRM, but I can't see one behind the kickplate and I don't have the gray plug associated with the TRC install. My rear bumper wiring looks same as your photos though so it seems the 7pin capability is standard with all Ranger wiring assemblies. That would imply there is some kind of wiring capacity to get a TRM installed, though it remains to be seen if one could be programmed once installed. Do you have the Towing app?

The only thing I did was install a Draw-tite receiver I bought from Amazon.
I haven't added the 7 -pin. I was waiting to see if Curt, Ford or any other manufacturer would offer a 4/7 harness that plugs into the existing bumper harness. All the wires for the 4/7 pin are there, at least on my truck. I just don't understand why Curt doesn't have all the wire on their harness or why adding the 7-pin means losing the 4-pin. As it stands, with Curt, you have to run wires to the cab for the trailer brakes, reverse lights and 12V power.
After a plug and play becomes available, I will add a TBC from RedARC or similar for around $200, rather than the more expensive Ford OEM parts. You can get the 4/7 pin from Ford, but the only offer the entire harness on the rear bumper, something like $600.

 

[Jason B]

Yeah, the Tow app is on the screen.
Even though we don't have a 'tow package' we can still tow with a ball on the bumper, or with the added receiver, that's why there is a 4-pin plug there. But that's limited to 3000 lbs.
FYI, I haven't had the need to tow anything yet, and don't know if I'll ever need a TBC, but I might add one 'just in case".

 

[pezdyspensr]

Yeah I generally tow light, but not having the capability in the moment feels foolish with a truck like this.

So if anyone has any actual experience with installing a TRM, wiring, and flashing it I would love to hear about it.

Yeah, the Tow app is on the screen.
Even though we don't have a 'tow package' we can still tow with a ball on the bumper, or with the added receiver, that's why there is a 4-pin plug there. But that's limited to 3000 lbs.
FYI, I haven't had the need to tow anything yet, and don't know if I'll ever need a TBC, but I might add one 'just in case".

 

[pezdyspensr]

So did you ever find a dealer willing to pop in a TRM and flash it? I am pretty sure they are available, but the question is more about supported wiring, or if the no-tow uses a different harness assembly than the others?

Ok, that is good to know. A this point, I'm thinking about tapping into a brake light, maybe even the CHMSL from the BCM.



This is what Ford said yesterday, that I don't have a trailer brake module. Just to confirm, the connector you mentioned has 4 wires: Power, Ground, BOO and Blue Trailer brake. Yes, they all work except that BOO (GRY/ORG) wire.



I'll have to ask the tech at the Ford service center on Monday about the BOO signal at the BCM. The real challenge is finding a tech who is competent enough to backup settings and methodically troubleshoot this without introducing other issues.

As for the 7-pin connector, there is no issue there. That is wired correctly by a local shop (not Ford).

Thanks for all your input and suggestions!

 

[HWMTB]

Hey there RangerDangerStranger,

Not sure if I'm the guy you referring to but, yeah, this was my situation exactly. I looked back in the thread and I guess I failed to report back that I did manage to get my RedArc controller working. I had to find the Brake On-Off signal from the center mounted brake light. I've been towing a small RV around and haven't had any trouble with trailer brakes. They work as expected. As for emergency braking... so long as that center brake light illuminates, the trailer brakes activate. I haven't been in a situation that activated emergency brakes (hope I never am) so I don't know for sure.

was a guy in this thread who was looking at adding a TBC to his Ranger without the basic tow kit. I believe he found the connector, but the brake signal from the BCM wasn't active in it, and there was no way to practically activate it from what I remember.

 

[Jason B]

Yeah I generally tow light, but not having the capability in the moment feels foolish with a truck like this.

So if anyone has any actual experience with installing a TRM, wiring, and flashing it I would love to hear about it.

When you plug in the 4-pin trailer connector, does the truck indicate 'trailer connected'? If it does, you already have a TRM. OR maybe I'm not understanding what the TRM does. What you don't have is a TBC, trailer brake controller. Rangers that have the basic tow option, have the receiver and 7/4-pin, but not a TBC. Rangers with the Advanced Tow Package have the TBC.

 

[HWMTB]

Hey Pezdyspensr (love the name!),

I haven't visited this topic in several months and my retention of the research I did since February is spotty. The dealership told me told once a Ranger (without tow package) leaves the factory, there is no way to add it afterward because Ford did not make the parts available. Maybe that has changed since February? Based on the link you shared in an earlier post, it might have!

As for the wire harness, I'm near certain it is the same harness as the basic/advance tow models; the only thing missing in the non-tow model is the TRM (in my opinion!) which I believe completes the circuit to/from the brake on-off signal and brake controller harness under the dash board. Again, this is my opinion; I have no facts to support it.

All that being said, I do have a working brake controller installed at this time and I've been pulling a 16' travel trailer (about 3500lbs) without an issue.

If you manage to get the brake controller working in your non-tow Ranger and you connect a trailer, I can tell you that the computer will recognize it! Sounds good, right? Nope. You can enter the trailer details and the computer will nag you about the trailer being overweight or dangerous.

The fix? Tell the truck nothing is in tow! Then, use Tow/Haul driving profile so the transmission shifts correctly. Don't rely on the computer to calculate "Miles to Empty" accurately. Plan ahead for fuel stops, especially if you are driving over mountains.

So did you ever find a dealer willing to pop in a TRM and flash it? I am pretty sure they are available, but the question is more about supported wiring, or if the no-tow uses a different harness assembly than the others?

 

[pezdyspensr]

Thanks for the clarifications! I have info from another thread whereby a Ranger owner who works in parts at a dealership successfully addressed this issue on a Bronco whereby they installed a TRM, harness, dash switch and used internal Ford programming to good success, which makes me think that it is possible. Dealerships seem to run their own versions of Ford policy when it comes to this stuff.
That said, I saw in an earlier post of yours that you were able to plug the Redarc into an available harness behind the kickplate? I am not finding the available grey plug for a TBC that others posted, and they all have the TRM and basic tow, so I wonder if you can confirm if yours is the same? And is it sticking out of the main harness bundle that flows into the firewall left of the brake? Or is it tucked further back behind trim? I am hoping I have this available at all. If not, I may be in an even worse position than you. The only difference of mine being a no-tow is that it's also an STX and not an XLT. Not sure if they skimped on wiring between models.

Hey Pezdyspensr (love the name!),

I haven't visited this topic in several months and my retention of the research I did since February is spotty. The dealership told me told once a Ranger (without tow package) leaves the factory, there is no way to add it afterward because Ford did not make the parts available. Maybe that has changed since February? Based on the link you shared in an earlier post, it might have!

As for the wire harness, I'm near certain it is the same harness as the basic/advance tow models; the only thing missing in the non-tow model is the TRM (in my opinion!) which I believe completes the circuit to/from the brake on-off signal and brake controller harness under the dash board. Again, this is my opinion; I have no facts to support it.

All that being said, I do have a working brake controller installed at this time and I've been pulling a 16' travel trailer (about 3500lbs) without an issue.

If you manage to get the brake controller working in your non-tow Ranger and you connect a trailer, I can tell you that the computer will recognize it! Sounds good, right? Nope. You can enter the trailer details and the computer will nag you about the trailer being overweight or dangerous.

The fix? Tell the truck nothing is in tow! Then, use Tow/Haul driving profile so the transmission shifts correctly. Don't rely on the computer to calculate "Miles to Empty" accurately. Plan ahead for fuel stops, especially if you are driving over mountains.

 

[HWMTB]

Yes, that’s right, the blue light pulses once and goes away when I push on the knob. Otherwise there’s no light.
I’ll try to find a trailer to test with soon.
Thanks.

G

Did you ever get your brake controller running correctly? I had the exact same issue with a non-tow package Ranger. And I don't think it has to do with the tester. If you still have the issue, I suspect your aren't getting the brake light on/off (BOO) signal.

 

[RangerDangerStranger]

let me add a little knowledge from earlier in the thread. The basic tow package trucks have a module that feeds everything needed in the seven pin connector. There's also a connector that you can plug into a aftermarket like ared arc made for the bronco which will give you a trailer break signal. A trailer brake controller. for non-tow package trucks, that seven pin module is not there. There is a more basic one for the four pin also, it seemed that the gray connector which would feed the trailer brake controller was there, which has power, ground, break on off and output to the seven pin. Everything was functional except the brake on off signal which comes from the body control Module was not active on the non-tow package equip trucks. The workaround was to tap the high amount of stoplight, which was done on the previous model as well,. That would give you your brake on off, signal under normal conditions and automatic emergency breaking. However, as yet I haven't seen the high mounted stoplight, tested under automatic emergency breaking. It can be done easily. Very slowly backing up towards a soft object like a bush with automatic emergency breaking on while not touching the brake pedal. The truck will automatically break and you can see if that light goes on. Now the 2025 had an option for the stock trailer brake controller without the advanced tow package. I'm not sure how well that would integrate into a 2024 but that also doesn't help the non-tow package equipment trucks. As far as I know, though even the non-tow package equiped trucks had that Connector for the trailer brake controller, even though the BOO signal is not active.

 

[goober71]

Did you ever get your brake controller running correctly? I had the exact same issue with a non-tow package Ranger. And I don't think it has to do with the tester. If you still have the issue, I suspect your aren't getting the brake light on/off (BOO) signal.

I have not tested it with a trailer with electric brakes yet. From what I understand, once I connect a trailer with electric brakes, the blue light will be on and steady, detecting the brakes. Will try this as soon as I can find a trailer with electric brakes. Any volunteers in the Houston/Sugar Land area with campers?

 

[HWMTB]

Thanks for the clarifications! I have info from another thread whereby a Ranger owner who works in parts at a dealership successfully addressed this issue on a Bronco whereby they installed a TRM, harness, dash switch and used internal Ford programming to good success, which makes me think that it is possible. Dealerships seem to run their own versions of Ford policy when it comes to this stuff.

This makes logical sense to me! I also saw several comments about the similarities between Bronco and Rangers.

That said, I saw in an earlier post of yours that you were able to plug the Redarc into an available harness behind the kickplate? I am not finding the available grey plug for a TBC that others posted, and they all have the TRM and basic tow, so I wonder if you can confirm if yours is the same? And is it sticking out of the main harness bundle that flows into the firewall left of the brake? Or is it tucked further back behind trim? I am hoping I have this available at all. If not, I may be in an even worse position than you. The only difference of mine being a no-tow is that it's also an STX and not an XLT. Not sure if they skimped on wiring between models.

This is interesting.... I definitely have the non-tow package (which I think lacks the TRM) and there is indeed a connector that accepts the RedArc brake controller wire harness. The connector has a "cover" on it and it is tucked up along the left footwell, zip tied to a large wire bundle near the firewall. See the picture below: The RED STAR is the "cover", the RED ARROW points to the connector in question. The YELLOW square shows female end of the RedArc harness.

 

[HWMTB]

let me add a little knowledge from earlier in the thread. The basic tow package trucks have a module that feeds everything needed in the seven pin connector. There's also a connector that you can plug into a aftermarket like ared arc made for the bronco which will give you a trailer break signal. A trailer brake controller. for non-tow package trucks, that seven pin module is not there. There is a more basic one for the four pin also, it seemed that the gray connector which would feed the trailer brake controller was there, which has power, ground, break on off and output to the seven pin. Everything was functional except the brake on off signal which comes from the body control Module was not active on the non-tow package equip trucks. The workaround was to tap the high amount of stoplight, which was done on the previous model as well,. That would give you your brake on off, signal under normal conditions and automatic emergency breaking. However, as yet I haven't seen the high mounted stoplight, tested under automatic emergency breaking. It can be done easily. Very slowly backing up towards a soft object like a bush with automatic emergency breaking on while not touching the brake pedal. The truck will automatically break and you can see if that light goes on. Now the 2025 had an option for the stock trailer brake controller without the advanced tow package. I'm not sure how well that would integrate into a 2024 but that also doesn't help the non-tow package equipment trucks. As far as I know, though even the non-tow package equiped trucks had that Connector for the trailer brake controller, even though the BOO signal is not active.

I can confirm this is accurate. I have the non-tow package and needed to tap into the center-high mounted brake light signal to get the BOO. Once this was done, the RedArc works brilliantly.

 

[HWMTB]

I have not tested it with a trailer with electric brakes yet. From what I understand, once I connect a trailer with electric brakes, the blue light will be on and steady, detecting the brakes. Will try this as soon as I can find a trailer with electric brakes. Any volunteers in the Houston/Sugar Land area with campers?

EDITED 9/18/25, 15:18 EST - I just saw another thread you started and I see where you stated you DO HAVE a tow package. If that is the case, then maybe your test will be different than what I experienced. Sorry to add to any confusion.

LOL... I'd be happy to help if I was nearby. This is EXACT same thing I did for testing. If your Ranger is like mine (XLT with no tow package), I don't think your going to be happy with the results. See the post #237; he summed it up really well. The missing piece of the puzzle will be getting the BOO to the brake controller, which in my case, is a RedArc.

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