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Trailer Brake Lights problem with Ford/Redarc controller

mtmanchris

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2021 Ford Ranger FX4 4x4 with factory tow package. I bought new in 2021 and have about 68000 miles on her now. I got a piece of equipment that weighs about 5000#, so I upgraded my trailer to a 2 axel, 7500# trailer with brakes on both axels.

I am used to towing with my Chevy 2500, but it is getting old and the Ranger should - and does - tow this new rig fine.

However, I needed a brake controller so I had a Ford/Redarc controller installed at the dealer. They located a new old-stock unit that they ordered and installed. I probably paid too much, but I live in the mountains of Western NC and want every advantage with the crazy drivers around here.

The controller is great as far as stopping the trailer, easy to adjust, looks factory, etc.

The problem is: When I manually activate the controller, the trailer brake lights don't come on, nor do the truck brake lights. My understanding is that this is the way it should happen. When using the peddle, everything works. When pushing the controller the brakes on the trailer work, but no lights are activated.

Does anyone have any thoughts. I think there is much more knowledge on this thread than at the dealership.

Thanks for any help! And I'm sorry if this has been discussed. I searched and read a lot!
CJ
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RangerBill

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2021 Ford Ranger FX4 4x4 with factory tow package. I bought new in 2021 and have about 68000 miles on her now. I got a piece of equipment that weighs about 5000#, so I upgraded my trailer to a 2 axel, 7500# trailer with brakes on both axels.

I am used to towing with my Chevy 2500, but it is getting old and the Ranger should - and does - tow this new rig fine.

However, I needed a brake controller so I had a Ford/Redarc controller installed at the dealer. They located a new old-stock unit that they ordered and installed. I probably paid too much, but I live in the mountains of Western NC and want every advantage with the crazy drivers around here.

The controller is great as far as stopping the trailer, easy to adjust, looks factory, etc.

The problem is: When I manually activate the controller, the trailer brake lights don't come on, nor do the truck brake lights. My understanding is that this is the way it should happen. When using the peddle, everything works. When pushing the controller the brakes on the trailer work, but no lights are activated.

Does anyone have any thoughts. I think there is much more knowledge on this thread than at the dealership.

Thanks for any help! And I'm sorry if this has been discussed. I searched and read a lot!
CJ
Yes, that is the way it works since the brake controller pushbutton activates the trailer brakes, but the truck has no way of knowing that you pushed the trailer brake button. I believe that normally you would use that button if the trailer is starting to sway, so you would just momentarily press it to straighten out the swaying. You wouldn't be using it to stop or slow the truck.
 

06Warrior

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I have the same brake controller on my 20’ XLT and installed it my self last year when Ford still had it in stock.

I don’t tow our travel trailer much but did notice last year it didn’t work correctly. I couldn’t adjust it with the knob. It really only worked when I pressed the button in.

Turned out the connector in the headliner was loose and the center high mount brake light stopped working.

I needed to fix it the day before our camping trip. I pulled the head liner down and cut the connector off and solder the wires together.

I also disconnected the connectors to the unit under the dash where I placed it, reconnected it and reset the unit and it worked fine for the camping trip last month.
 
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mtmanchris

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Yes, that is the way it works since the brake controller pushbutton activates the trailer brakes, but the truck has no way of knowing that you pushed the trailer brake button. I believe that normally you would use that button if the trailer is starting to sway, so you would just momentarily press it to straighten out the swaying. You wouldn't be using it to stop or slow the truck.
This is what I am used to on the older controllers, but my understanding is that the redarc will send a signal to both the truck brakes lights and trailer brake lights to activate when the manual button is pushed. I think this is a good safety feature and would like it to work. I'm worried that something was wires incorrectly at the time of install.
 
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mtmanchris

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I have the same brake controller on my 20’ XLT and installed it my self last year when Ford still had it in stock.

I don’t tow our travel trailer much but did notice last year it didn’t work correctly. I couldn’t adjust it with the knob. It really only worked when I pressed the button in.

Turned out the connector in the headliner was loose and the center high mount brake light stopped working.

I needed to fix it the day before our camping trip. I pulled the head liner down and cut the connector off and solder the wires together.

I also disconnected the connectors to the unit under the dash where I placed it, reconnected it and reset the unit and it worked fine for the camping trip last month.
Sounds like it is working now. Which must be a relief.
I usually do my own installs, but didn't this time. So trouble shooting may be more of a pain. I'm debating whether to look for the problem myself, or take it back to the dealer.
Can you tell if the trailer brake lights come on when you manually activate the controller?
Thank
CJ
 


06Warrior

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Sounds like it is working now. Which must be a relief.
I usually do my own installs, but didn't this time. So trouble shooting may be more of a pain. I'm debating whether to look for the problem myself, or take it back to the dealer.
Can you tell if the trailer brake lights come on when you manually activate the controller?
Thank
CJ
Unfortunately I won’t be able to check it for almost 2 weeks due to a health issue but soon as I can I will.
 

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This is what I am used to on the older controllers, but my understanding is that the redarc will send a signal to both the truck brakes lights and trailer brake lights to activate when the manual button is pushed. I think this is a good safety feature and would like it to work. I'm worried that something was wires incorrectly at the time of install.
This is not true. The truck sends a signal to the Redarc to activate the trailer brakes, not the other way around.
 
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D K

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Not to bring a thread back from the dead, but does anyone have pictures of the installation?
 

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There are numerous threads on this install and even a YouTube video, however this specific Redarc TBC with included Lumen module is no longer in production and the only way to get this specific (combination) was from Ford, the combo adds the extra Lumnen module for brake pedal (Brake Lights) input as the brake lights are (Can Bus) if the truck triggers (AEB) feature, this unit taps the CHMSL for that input via the brake light signal - I would have to locate the exact thread its in - But I went (In-Depth) on the operation and why it matters, any of the aftermarket TBC's will work , it's just that they will not include any (AEB) tie in if the Automatic Emergency Braking - triggers the trailer brakes will not engage as you will not be physically pressing the brake pedal, granted you are only talking about a few seconds for your actual reaction to hit the brake but it is enough to offset a heavy trailer and momentum push the truck forward or jackknife the trailer.

I personally do not tow with my truck so others may be able to give you the best options outside of this (combo) as by now I highly doubt you will find one since they have been discontinued for some time now, note as others have reported numerous sites list it in-stock only to be refunded the money and informed out of stock - discontinued.
This is the unit you really want - If you are lucky to get one

I actually found the thread with the operation breakdown regarding the Lumen module

Ford warns that Active Cruise Control can NOT be used with an aftermarket trailer brake controller | Page 14 | 2019+ Ford Ranger and Raptor Forum (5th Generation) - Ranger5G.com
 
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airline tech

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To understand the difference -
if you physically press the brake pedal the TBC activates the trailer brakes - normally

If AEB or ACC is triggered - that brake pedal input is no longer in play, and the truck can apply the brakes automatically - the truck's brakes apply but not the trailer braless, however when the brakes automatically apply, the brake lights also apply without you even touching the brake pedal.

The extra Lumen module - picks up (Brake Light) applied via the CHMSL and the trailer brakes apply along with the truck's brakes as the module allows for a pickup of that light (on) signal the standard TBC's without this module - do not see it and only use the physical movement (Input) of the brake pedal from the (Brake Switch) or BOO signal
 

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Thanks for that, although, I wouldnt want AEB with a trailer hooked up anyway. Also, I dont know why I would want the light trigger if it didnt come from the brake pedal.

I probably easily have over a 100K towing and I can't remember a single time that I thought it would be a good idea for the trailer brakes to come on when manually hitting the trailer brakes.

I might be missing something though..

There are numerous threads on this install and even a YouTube video, however this specific Redarc TBC with included Lumen module is no longer in production and the only way to get this specific (combination) was from Ford, the combo adds the extra Lumnen module for brake pedal (Brake Lights) input as the brake lights are (Can Bus) if the truck triggers (AEB) feature, this unit taps the CHMSL for that input via the brake light signal - I would have to locate the exact thread its in - But I went (In-Depth) on the operation and why it matters, any of the aftermarket TBC's will work , it's just that they will not include any (AEB) tie in if the Automatic Emergency Braking - triggers the trailer brakes will not engage as you will not be physically pressing the brake pedal, granted you are only talking about a few seconds for your actual reaction to hit the brake but it is enough to offset a heavy trailer and momentum push the truck forward or jackknife the trailer.

I personally do not tow with my truck so others may be able to give you the best options outside of this (combo) as by now I highly doubt you will find one since they have been discontinued for some time now, note as others have reported numerous sites list it in-stock only to be refunded the money and informed out of stock - discontinued.
This is the unit you really want - If you are lucky to get one

I actually found the thread with the operation breakdown regarding the Lumen module

Ford warns that Active Cruise Control can NOT be used with an aftermarket trailer brake controller | Page 14 | 2019+ Ford Ranger and Raptor Forum (5th Generation) - Ranger5G.com
 

airline tech

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The Brake Light - On with AEB - lets the vehicles behind you - see brake lights be it from you hitting the brake pedal or the truck automatically braking for you.

The standard TBC uses the pre-wired loop that is in the LH Kick Panel (blue taped wrapped) and capped off. The (Violet / White) wire is the TBC input for the brake pedal being applied and when you press the brake pedal the TBC sends the brake apply signal to the trailer along with the truck brakes.

The Lumen module - skips that input and uses the CHMSL as the brake applied (input) so if you or the truck applies the brakes the trailer will apply the brakes via the TBC

So, the only difference is where the brakes applied signal comes from, if using the standard TBC the trailer will only apply the brakes If you physically press the brake pedal as the TBC will not see the brakes being applied (automatically) by the truck

FYI - There is an option in the IPC Menu - to turn off AEB but its only good for the current ignition cycle then it resets to active
 

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Thanks for that, although, I wouldnt want AEB with a trailer hooked up anyway. Also, I dont know why I would want the light trigger if it didnt come from the brake pedal.

I probably easily have over a 100K towing and I can't remember a single time that I thought it would be a good idea for the trailer brakes to come on when manually hitting the trailer brakes.

I might be missing something though..
If the truck senses an imminent crash, it will automatically apply the truck brakes. If the TBC is connected to the brake pedal switch for the brake signal, the trailer brakes won't be applied with disastrous results possible.
 
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Cabose-1

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I had the rearc on my 2022 ranger. I used the wires on the driverside footwell. It worked just fine. Hit the brakes manually and brake lights came on truck cruise control came off. I would check the wiring st the connection points. Make sure its all working. I dont know about emergency braking or automatic, it has never turned on.
Yes the whole argument about emergency braking is out there.
But the redarc i had worked manually turning on all. Brake lights and even turning off cruise. Id double check the wiring at the driver side footwell. Make sure iys all connected proper
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