Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional
Universal Wiring Adapter for Curt Trailer Brake Controllers

Part Numbers: C51140,C51515

Retail:$183.20
Our Price: $110.66
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Curt Electric,Electric over Hydraulic Trailer Brake Controller - C51140
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Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional
part number: C51140

Proportional brake controller automatically levels when mounted within a 90-degree vertical range and a 40-degree horizontal range. Includes digital display, 9 sensitivity settings, reverse-polarity protection, and continuous diagnostics.

Features:

  • Brake controller activates trailer brakes in proportion to your vehicle's braking action
    • Automatically adjusts trailer's braking based on deceleration of tow vehicle
    • Activates immediately - no pausing like with time-delayed brake controllers
  • Automatic-leveling ability - internal sensor detects deceleration even if controller is not mounted flat
    • Position within 90 degrees up or down and within ±20 degrees side to side
  • 9 Sensitivity settings (boost settings) let you adjust initial braking power and aggressiveness
  • Triple-axis accelerometer is highly responsive, ensuring smooth, uniform stopping action
  • Continuous diagnostic check alerts you to any potential problems
  • Integrated safeguards protect your vehicle, the trailer, and the controller
    • Minimizes drain on car battery by entering power conservation mode after 30 minutes of inactivity
    • Keeps trailer brakes from overheating by reducing power output to them during prolonged stops
    • Defends brake controller and trailer breakaway systems against shorts
    • Prevents positive and negative power reversal with built-in polarity protection
  • Surface-mount technology (SMT) allows for consistent, reliable performance
    • Maximizes power output while producing minimal heat
    • Ensures superior operation in rough road conditions
  • Digital display communicates power and sensitivity settings and error codes
  • Built-in, slide-bar manual override
  • Mounting bracket and hardware included
    • Plug-in, vehicle-specific brake control adapter (sold separately) can be used for certain applications to reduce installation time


Specs:

  • Application: trailers with up to 4 axles (8 brake assemblies)
    • Designed for use with electric or electric-over-hydraulic trailer brakes
  • Dimensions: 3-1/4" wide x 4" long x 7/8" tall
  • Mounting:
    • 90-Degree vertical plane operating range
    • 40-Degree horizontal plane operating range
  • Limited lifetime warranty


Note: If your vehicle's 7-Way trailer connector has LED test lights built into it, the TriFlex brake controller will not be compatible.



Proportional Braking

With a proportional brake controller, you can get heavy-duty emergency braking, general braking, or slow-to-an-idle braking for your trailer automatically. The intensity with which your trailer brakes are activated and the rate at which they are applied are dependent on the deceleration of your tow vehicle. This means that, unlike time-delay controllers - which send the same amount of preset power to your trailer brakes every time - proportional controllers are able to adapt to every braking situation differently. So, if you slam on the brakes in your truck, your trailer brakes will activate with that same extreme intensity. And if you merely slow down as you approach a red light, your trailer will gradually brake in the same manner. Just set the initial power level, select a sensitivity setting, and you're good to go.


As long as the TriFlex controller is properly mounted as indicated in the instructions, it will sense - via an internal inertia sensor - how your tow vehicle brakes. This triple-axis, inertia-based sensor responds to the deceleration of your tow vehicle as you brake by signaling the controller to send out enough power to your trailer brakes so that they are activated with an intensity that matches. The result is uniform braking across your towing setup. No push-pull action - just smooth, proportional braking every time.


Built-In Controls for Adjustable Power

Curt TriFlex Controls and Components

The above diagram shows the controls and components of the Curt TriFlex trailer brake controller.

  1. Digital display
  2. Thumbwheel power output control
  3. Sensitivity adjustment switch
  4. Slide-bar manual override

Output Control

During the initial setup process, use the thumbwheel on top of the TriFlex to adjust the output. The output control lets you set the maximum amount of power that will be applied to your trailer's brakes. Typically, the output is only readjusted when you experience changing road conditions or if you switch over from a heavy, loaded trailer to a much lighter, empty trailer, or vice versa. To get more power to your brakes, rotate the switch to the right. To decrease the power output, move it to the left. The output setting will appear on the digital display when you press the brake pedal or activate the manual override.


Sensitivity Settings

Once you have the overall power set, you can fine-tune the power output by adjusting the sensitivity of the internal sensor. Use the switch on the side of the TriFlex to achieve your desired degree of intensity.


Move the switch toward you to boost the power output, causing your trailer brakes to activate with more intensity right off the bat. This means that they will also reach maximum braking faster simply because they will start out at that higher intensity. This is particularly beneficial if you are towing a heavy load because the intensity required to stop that load may be far greater than that needed to halt your vehicle. Therefore, sending out more initial power to the trailer brakes - and causing them to reach maximum braking faster - allows you to better control the trailer so that it doesn't push your tow vehicle before coming to a complete stop.


There are 9 sensitivity levels (boost levels), with 1 being the least sensitive. At level 9, the sensitivity of the internal sensor is as high as it can go. When you change the setting, the display on the TriFlex will flash the level before reverting back to showing the power output.


Safety Features

The TriFlex offers advanced safety features to prevent damage to various components of your towing setup. When the TriFlex is not in use, it will be in power-saving mode, reducing the power draw to minimize drain on your vehicle's battery. This power-conservation mode begins after 30 minutes of inactivity and ends the moment your vehicle's brake pedal is pressed.


When you stop at red lights, or any time that your truck and trailer are at a standstill with the brakes applied for a prolonged period of time, the TriFlex will reduce the power output to your trailer's brakes, preventing them from overheating.


If ever there is a time that you need to brake your trailer separately from your tow vehicle, the manual override lever is easily accessible. Pushing this slide engages the brakes on your trailer with either full power or the maximum power allowed by the output level, depending on which setting you select. In addition, when you activate this override, the brake lights on your trailer will illuminate, properly warning those behind you of the braking action of your rig.


Automatic Leveling and Simple Installation

The self-leveling feature of the TriFlex ensures that the brake controller continues to function even as you drive up steep hills or through the mountains. Simply mount it in your cab at a vertical angle that is within 90 degrees, and the controller will level itself automatically. Make sure that the controller is also positioned so that the side-to-side angle is within ±20 degrees.


Installation is a snap. After mounting the TriFlex unit in your cab using the included bracket, hardwire one end of the included pigtail harness directly into your vehicle. The other end plugs into the brake controller. To transfer the TriFlex to another vehicle or to remove it for storage, just unplug the unit and remove the screws that hold it place in the bracket. Curt offers a spare mounting bracket (C51144 - sold separately) that can be used to affix the TriFlex in your other automobile.


Installation Accessories

For even easier installation, a vehicle-specific wiring adapter (sold separately) is available for most newer trucks and SUVs. One end of the custom adapter plugs into your vehicle, and the other end plugs into the controller - no hardwiring required.


Note: If a custom brake control wiring adapter is not available for your vehicle, one of the following will be required:

20-Amp circuit breaker (9506P - sold separately) for 2- to 4-brake applications

30-Amp circuit breaker (38630 - sold separately) for 6- to 8-brake applications


See also etrailer.com's exclusive 7- and 4-way brake control installation kit (ETBC7 - sold separately) if you don't already have a 7-way plug at the back of your vehicle.


Surface-Mount Technology

Curt's TriFlex brake controller is built using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability, and durability.


Curt SMT Circuit Boards

Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? SMT circuit boards also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.


Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.



51140 Curt Tri-Flex Proportional Trailer Brake Control

California residents: click here



Universal Wiring Adapter for Curt Trailer Brake Controllers
part number: C51515

This wiring adapter is designed for vehicles that do not come equipped with a factory brake control wiring harness port. One end plugs into your Curt trailer brake controller while the other end splices into your vehicle's wiring.

Features:

  • Universal wiring adapter eases installation of your electric trailer brake controller
    • No need to wire brake controller directly to your vehicle
  • Wire end splices into your vehicle's wiring
    • Use on a vehicle that does not have a factory tow package or on one that has a brake control harness but is not equipped with a plug-in port
  • Connector end joins with the plug on your electric brake controller
    • Compatible with time-delayed and proportional brake controllers from Curt
    • Simple to plug and unplug control for removal
  • 2' Long, 12-gauge wires have protective covering to deter damage
  • Limited 1-year warranty


Installation of Curt Brake Controller Adapter

To install your Curt electric brake controller, you need to connect the wiring of the controller to your vehicle. Certain auto manufacturers offer pre-wired options, typically known as tow packages, wherein wiring is run for you from the dash to the trailer connector on the back of your vehicle. Usually when this is done, a port is installed at your dash so that you can easily plug in a brake controller. However, if no port is present, you will have to splice into your wiring.


With this universal adapter, you can install your Curt brake controller without having to wire the controller directly to your vehicle. If your vehicle has a factory tow package, just splice the pigtail end of the adapter into your vehicle's factory brake control harness wiring, and then plug the other end of the adapter into the controller. If your vehicle doesn't have a factory tow package, you'll have to hardwire the pigtail end of the adapter into your vehicle's wiring. Because only the adapter is hardwired to your vehicle, you can unplug and remove your brake controller at any time to transfer it to another vehicle or securely stow it away.


If your vehicle is not equipped with a factory tow package, you will need to purchase additional equipment to ensure that the signals from your brake controller are sent to your trailer's brakes. We recommend etrailer.com's exclusive 7- and 4-way brake control installation kit (ETBC7 - sold separately).



51515 Curt Universal Quick Plug Brake Control Adaptor Harness with Pigtail

California residents: click here





Customer Reviews

Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional - C51140

Universal Wiring Adapter for Curt Trailer Brake Controllers - C51515

Average Customer Rating:  4.8 out of 5 stars   (595 Customer Reviews)

Proportional brake controller automatically levels when mounted within a 90-degree vertical range and a 40-degree horizontal range. Includes digital display, 9 sensitivity settings, reverse-polarity protection, and continuous diagnostics. This wiring adapter is designed for vehicles that do not come equipped with a factory brake control wiring harness port. One end plugs into your Curt trailer brake controller while the other end splices into your vehicle's wiring.

- C51140
by: Jason J.06/24/2019

Easy to set up and operate. The controls are less than intuitive. There’s a sensitivity dial and a force level slider that seem to affect the application of the brakes. It’s not exactly clear which one is more important or has the most impact. The unit works well at highway speed but at low speed operations seems to apply the brakes aggressively to the trailer. This is my first experience with a brake controller so can’t compare with other units. It does make parking lot operations somewhat clumsy. It definitely gets the job done though. 662164


Comments
Poorly. The tekonsha prodigy is so much better than this unit.
Jason J - 06/25/2020

82030

- C51140
by: Bill02/26/2019

seemed to work great towing our 16' iPod travel trailer! 608503



- C51140
by: Tammy H.01/01/2017

I connected the Curt Brake controller into my 2007 Toyota 4runner. It took 5 minutes to hook up using the curt wiring adapter for my vehicle. I pulled a 16' aluminum stock trailer with one horse in it. There were no problems with braking and the braking action was very smooth on the trailer. I also have a weight distribution on the trailer which helps with using the Toyota in an "emergency" tow. The horse had an easy 3 hour tow with smooth braking and no swaying. Thanks etrailer for all the tools that make farm life easier. 329228



- C51140
by: Vincenzo09/05/2018

Wow! All works to perfection ! From the Website wade of specification of what I needed for my set up to fast delivery and plug n play install ! This is my second order from etrailer & will be for all my needs! I installed it to my right knee side , so not to hit it in & out daily, but any place will work - tie up extra wire securely. Safe journey !! 561685



- C51140
by: Dave10/14/2018

I am very excited to try it, however the quick connect, doesn't seem to fit my 2004 3/4 ton Chevy Express van. Th brake control harness #51451. It's for the Trifles brake controller. If it is the correct harness I cannot find where to plot in . The vehicle end of the harness will not fit available spots on fuse block . Any help would be appreciated. Thanks Dave 574308


Comments
The 2004 Chevrolet Express Van does not have a plug and play adapter available for the brake controller at this time. The C51451 will not have a place to plug in in your vehicle. The adapter you will need with the curt triflex is part # C51515
Universal Wiring Adapter for Curt Trailer Brake Controllers
$15.94
. The part C51515 pig tail plugs into the wiring that is coming out of the back of triflex. There is some wiring that needs to be done with this brake controller installation. If your 2004 Chevrolet express van has a towing package from the factory the blue brake wire is already ran from the back of the vehicle to the front. It is located under the dash near the emergency brake pedal. The blue wire from the brake controller wiring pigtail will butt connect to the blue wire that was ran from the factory. You will also need kit part # 5506
Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers
$73.50
. Using the duplex wire from the kit you want to butt connect the black wire to the black wire coming from the brake controller. Using a ring terminal connect the black wire to the 30 amp circuit breaker included in the kit that you will install under the hood. Then using an extra cut piece of black wire connect from the circuit breaker to the positive side of the battery. The white ground wire will then connect to the negative side of the battery. The red wire from the brake controller butt connects to the brake switch wire and will need to be located in the van. In a Chevrolet express van the brake switch wire is normally light blue and located in the Body Control Module of the van. The BCM is normally located behind the passenger side dash. The brake switch wire on the van is typically the light blue wire but you want to use a circuit tester to test for function. You are looking for the wire that only shows power when the brake pedal is pressed. Once you have located that brake switch wire, connect the red wire from the brake controller to that. If your chevrolet express van has a towing package it should have a round plug with a cap inside the drivers side frame rail at the back of the van. You can now use a part # 30955
Replacement Custom Multi-Tow 7-Way and 4-Way Trailer Connectors
$38.31
to give the van a 7 way connector. If your van does not have a towing package the blue wire will not be ran for you. You will need part # ETBC7
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
$111.95
and not the part # 5506
Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers
$73.50
. The ETBC7 includes the 7 way connector, circuit breakers and duplex wire. The 7 way connector will need to be wired to the front of the vehicle before you can finish the installation I described above using the duplex wire in the kit. You also need a 4-way connector to plug into the 7 way connector part # 118392
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
$22.78
for the 2004 Chevrolet express van. I have attached FAQs on wiring in a 7-way connector.
-- Heather A - 10/16/2018

44706

- C51140
by: William g09/22/2018

Fortunately my F150 had the trailer package so the pigtail plugged right in. Only snag was I had to fabricate a piece to attach to the instrument panel (lower right) to get the correct angle they specify. That took some work. But it all came together nicely. See attached picture. The brake control works great. Good price. 567828



- C51140
by: Mainly Dave07/22/2015

Installed and use on a 2014 FJ Cruiser. Need the wiring kit for the FJ. Installation was straight forward and everything needed was included. Took me about 2 hours but no problems. Using the unit is easy to understand. My only concern is that it does not seem to be able to lock up the brakes [even with the manual function.] But this might be due to my brakes being worn and not used recently. Have towed a fairly heavy load once [~3500 lbs,] and I am pleased with the braking function. I recommend the product. 213490



- C51140
by: Mel08/21/2019

I got home early today from work and found my brake controller waiting for me.(The one thing I did not like seeing was that, although I have a drop box for all parcels next to the fence, it was placed on top of the box. LAZY DELIVERY PERSON! ) Anyway, I took it in and looked it over and decide to do the install. It took longer for me to get the cover off the box where the plug goes,then to do the entire install. Since I didn't want to drill any holes(yet) I used an existing screw down low. Now, I'm just waiting for my son to bring his dump trailer over,which he will leave with me for a few months. Stay tuned,more pictures and review still to come. 692045



- C51140
by: Mike R.09/22/2014

Small size is convenient - easy to mount in a Tacoma. When setting it up for a single-axle 2,200-pound tent trailer with a brand new Dexter axle, I was surprised to find I have to run at the maximum output and sensitivity settings, but it works fine. 152489


Comments
Make sure the brakes are properly adjusted. They should be exerting a slight drag on the drum when spinning by hand. If the brakes are not adjusted correctly, you may be exerting more wear on the magnet than is necessary.
-- Patrick B - 09/29/2014

7032
Comments
I dont know what changed, but the controller is working as expected now - I am pleased with its performance and convenient size.
Mike R - 09/16/2015

15030

- C51140
by: Alan11/17/2017

2003 Ranger XLT Installation was fun! I tend to ignore instructions especially when those instructions mount the device where my knee is constantly banging into that device. See the photo. Would loved to have a longer extension cable to reach into engine compartment. If you are not mechanically and electrically gifted, have somebody that is do the installation. Had the device not initialize once at the beginning of a trip. After thirty minutes of trouble tracing, decided nothing was wrong, unplugged the cable for a few minutes then reconnected and initialization completed correctly and I had brakes. Now I unplug the device whenever I'm not towing. 452856



- C51140
by: Howard S.04/06/2017

I bought a 7 pin trailer wiring/brake connection for my Dodge pickup. I installed it myself, the instructions were absolutely clear and correct. It was an easy installation. In the year since, I've pulled my trailer (tandem axle, 16') many times. The brakes continue to work perfectly as well as the lights. The connectors are solid, all work just like new. I recommend Etrailer parts and their people 100%! 363500


Comments
Still using the products no problems, everything’s works great.
Howard S - 04/06/2018

36954

- C51140
by: Jeff H.08/01/2013

Items arrived quickly. Hesitant to buy "Drawtite",as I was told 'Made in China". However, it says on label 'Made in USA'! Needed additional spacer for 'middle' bolt.? Fairly easy install. Curt brake controller should be easy as well. All in all, a 'square deal! 92715


Comments
Hitch is fine.Curt controller had a malfunction, factory support -superb! Sent a new unit in 2 days!
Jeff H - 01/30/2015

9096

- C51140
by: Joe B.11/21/2015

Easy to install and set up. I can't believe the difference between this proportional controller and the simpler time delay type. Between the power output adjustment and the sensitivity adjustment, you can quickly and easily adjust the controller for your trailer. It took me about 5 minutes to dial it in perfectly! No more jerky trailer brakes! Thank you E-Trailer! 232383



- C51515
by: Mainly Dave07/22/2015

Recently used this kit to install electronic brakes on a 2014 FJ Cruised. Absolutely essential and worth every penny! Instructions straight forward and everything included! 213491


Comments
Have been using this product for a year now. Commonly haul 2-3 tons. Absolutely no problems and the braking system works well. Adjustments based on load are easy. Highly recommend!
Mainly D - 07/22/2016

19561

- C51140
by: Jon02/11/2019

Installed in my truck only took about a hour plugs in to the original 604157



- C51515
by: Robert09/30/2018

Product was easily located on website and was exactly what I was looking for. I had forgotten to take off of my old vehice before I sold it, so this allows me to plugin my Curt brake controller without having to cut the connector off of it. 570389



- C51515
by: Frank S02/14/2014

this went into my VW Touareg which requires the relay modification described in the Technical Bulletin. Because ground and +12V is already present in the harness, instead of running additional cables, I soldered the relay right into the cable, making it a clean plug and play setup which is 100% removable. I also bought the VW housing and wire kit to complete the install 116584



- C51515
by: BiscuitsNGravy10/21/2013

I own a 2008 Chevy Silverado. I ordered the brake controller - C51515 and the universal wiring adapter on Friday and received it on Tuesday. My friend who is a mechanic installed it in about an hour on Wednesday. I towed my camper trailer to Lincoln, NE (about a 5 hour trip) on Thursday and returned on Sunday. After reading the settings instructions, all stops were made smooth and firm. Etrailer.com was great and the Curt Trailer Brake Controller is excellent! 104632


Comments
I have enjoyed the use of the electric brake controller. The stops are always safe and smooth. Im glad I got it for my truck and Ive never had a problem with it. I just need to get out and use my camper more! The initial contact with etrailer.com was very favorable and I will do business with them again when I need something for my trailers or tow vehicles.
BiscuitsNGravy - 10/21/2014

7356

- C51140
by: Rick10/10/2018

Works very well ! 573332



- C51140
by: Chris H07/31/2017

I purchased this controller along with the direct fit wiring harness and 7 way trailer harness for my 2000 F250SD. Install was easy. I would highly suggest buying the direct fit harness with this controller (I was replacing a spliced in system that was having intermittent issues). The only trailer I tow with brakes is an 18' landscape/utility trailer that may be loaded with 1000# one week and 7000# the next, so the inertia driven system should make for a much smoother ride. Service was great, really appreciated the follow up email to make sure the product arrived in good order and all my needs had been met. Etrailer will be my first stop for trailer related needs in the future. 412923



- C51140
by: Tom and Anita09/19/2016

Yes I received my order and installed the brake controller. All seems to be fine, although I have yet to tow with it yet. Here are a couple photos of the installation in my 2010 Toyota Tundra. 296409



- C51140
by: Jason S07/30/2017

I recently bought a Kurt trailer brake controller with adaptor. I have to say, that it was the easiest thing to hook up. The product was also shipped to my home very fast. I did not think I was going to receive the package until the next week, but it came just in time to use it the following day for my work. i Love ordering products from etrailer, I have only had really great service and good products from them. I will for sure, order from them again. 414526



- C51515
by: David03/27/2019

Not much to say about this. Is what it is. Plugs in to the curt triflex brake controller nice and firm. A little longer (it’s about 2’ long) than I needed in my 2011 Silverado but the excess wire tucked away nicely. 614612



- C51515
by: Kent E.06/05/2016

Wiring up a brake controller can be tricky. Routing the wire from the hitch to the firewall and finding the right wire on the brake are the hardest part, but etrailer will do their best to help. Consider running the wire inside the car along the door bottom just under the carpet. This avoids problems with the tie-wraps under the car -- there just isn't anywhere to tie wrap under the middle of the car. Use "loom clamps" ordered separately to solve this problem, if you go under the car. To find the right brake wire without cutting insulation, use the fish wire from the hitch install to contact the end of the wire inside the connector (from the back). Then touch the fish wire with the continuity tester and apply the brake pedal. My brake had a four wire connector and I found the right one on the second try. If you find a hole in the firewall with a rubber plug in it, don't discard the plug. Make a short slice in it with a razor blade and push the wires through. You may have to work the wires around to get them through the carpet. Be patient. Be sure to watch all the videos and allow plenty of time, taking a break before you tackle the hard parts. Rest assured that doing it yourself is better than allowing UHaul to cut corners and charge you labor. :-) If you are doing the hitch install and four-wire harness, those are much easier. If you are installing the hitch alone, be sure to have a magnet wand for when you push the bolt up into the frame rail. If I had it to do again, I would use a little electrical tape to hold the bolts down so a slight bump wouldn't knock them up. 257414


Comments
Ive not had any trouble with the hitch or the brake controller. I can tow my tear trailer anywhere I want and the hitch protects my mufflers from damage when I go offroad. Nice extra benefit.
Kent E - 01/23/2018

33496

- C51140
by: Marion09/14/2020

Works very well. Very easy to use and I don’t have to think about my trailer pushing my truck. 880548


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Ask the Experts about this Trailer Brake Controller


  • Where Is the Brake Controller Plug on a 2008 Dodge Ram 1500
  • The correct brake controller adapter plug you are looking for is blue however, it will only have four pins as you mentioned which means the one you have located in not correct. The correct plug you will be looking for and can find in the attached photo is located to the left of the intermediate shaft on the steering column. This plug can also be seen in the attached video. The correct adapter for you if you have a Curt brake controller like the Curt TriFlex Trailer Brake Controller part
    view full answer...

  • How To Install Curt Brake Controller On 2018 Jeep Cherokee with Tow Package
  • The Curt TriFlex Trailer Brake Controller part # C51140 with Curt Custom Wiring Adapter for Trailer Brake Controllers part # C51459 is an excellent option for a 2018 Jeep Cherokee with tow package. The brake controller will mount on the dash within reach and then the custom adapter will plug into the rear of the controller and then the tow package port on the vehicle which is located underneath the dash, just to the left of the steering wheel, taped to another harness near the emergency
    view full answer...

  • Troubleshooting Curt Triflex Brake Controller that Won't Power On Installed on 2018 Ford F-150
  • The install harness part # C51436 is the correct harness to install the Curt Triflex part # C51140 in your 2018 Ford F-150. What I would do is verify the controller wiring has power on the black wire as this is the power circuit for it. You'd want to use a circuit tester like part # PTW2993 for this. If there is no power there then check under the hood for a blown fuse for the brake controller power circuit. If there is power there then you most likely have a bad brake controller as with
    view full answer...

  • Parts Needed to Install Curt TriFlex Brake Controller in GMC Van and Ford F-53
  • To install the Curt TriFlex # C51140 trailer brake controller in your 2006 GMC Savana Van you will need to wire in harness part # C51515. Vehicles with the 7-way tow package have the blue output brake wire already run from the back to the front. It is located under the dash near the emergency brake pedal. This connects to the blue wire on the harness. The white wire connects to battery negative, the red wire connects to the cold side of the brake light switch and the black wire connects
    view full answer...

  • Can Curt TriFlex be Used With 2019 Toyota Highlander
  • So long as your 2019 Toyota Highlander does not have the factory tow package, you can use the Curt TriFlex Trailer Brake Controller # C51140 you referenced. To use it you will need the Wiring Adapter # C51515, T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118449 and Universal Installation Kit for Trailer Brake Controller # ETBC7. If your '19 Highlander has the factory tow package I strongly recommend the Curt Echo Mobile Trailer Brake Controller # C51180 because it
    view full answer...

  • How do I Install The Curt Triflex in my 2000 Chevrolet Aatro Van
  • To install the Curt TriFlex Trailer Brake Controller part # C51140 you will use the Universal Wiring Adapter for Curt Trailer Brake Controller part # C51515. This will get connected to the Universal Installation Kit for Trailer Brake Controller part # ETBC7 to get the signals to the back of the vehicle for you. This is assuming your have a working four pole already there. If you do not add the Curt Vehicle Wiring Harness with 4-Pole Flat Trailer Connector part # C55411 to have the starting
    view full answer...

  • Curt Brake Controller Adapter For 2019 Ford Expedition
  • I am happy to help you install the Curt Triflex part # C51140 in your 2019 Ford Expedition with a factory 7-way. I recommend to use Curt Custom Wiring Adapter for Trailer Brake Controllers part # C51436 to install the brake controller. It will plug into a built-in port under the dash of the Ford and the other end plugs into the brake controller to power the brake output circuit on the 7-way to tow a trailer with brakes.
    view full answer...

  • Choosing Proportional or Time Delayed Brake Controller for Truck with Manual Transmission
  • The Curt TriFlex Trailer Brake Controller # C51140 and Universal Wiring Adapter # C51515 is an excellent choice for your 1986 Ford Ranger with a manual transmission. Proportional brake controllers like the Curt TriFlex have an internal inertia sensor which responds to the deceleration of your tow vehicle. Letting your foot off the gas pedal for a few seconds to shift gears does not create enough of a deceleration to send the signal to engage the brakes on the trailer. The controller
    view full answer...

  • Brake Controller Installation on my 2017 Audi Q7
  • With the Curt Triflex part # C51140 and the Curt Adapter part # C51522 you will have all you need to successfully install your controller. I have linked a video for you showing the operation of the controller. Check it out to familiarize yourself with it.
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  • How To Use Curt TriFlex Trailer Brake Controller On a 2018 Ram 1500
  • The Curt TriFlex Trailer Brake Controller part # C51140 is an excellent option for a 2018 Ram 1500. That said, you'd also need the Curt Custom Wiring Adapter for Trailer Brake Controllers part # C51458 for plug-in-play installation. In regards to the factory brake controller, these aftermarket options are much more reliable and offer better performance. There is really no comparison and many swap out the factory brake controller for an aftermarket brake controller.
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  • Recommended Out of the Way Brake Controller for 2009 Ford F-150 With Factory 7-Way
  • The Curt TriFlex Trailer Brake Controller # C51140 with Wiring Adapter # C51436 is a very good option for your 2009 Ford F-150, though to mount it you will need to use the included mounting bracket and screw it in under the dash. If you (understandably) don't want a brake controller unit in the cab of your F-150, you do have a great option I recommend checking out, the Curt Echo Mobile Trailer Brake Controller # C51180. The Echo is the best option because it will simply plug into
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  • Which Trailer Wiring Harness is Needed to Install Curt Triflex in 2020 Chevy Silverado 1500
  • The Curt TriFlex # C51140 that you have can be used in your new 2020 Chevy Silverado 1500 but you will need a new harness as there where some changes between the 2017 and 2020 models. So what you'd need is just the part # C51525 and you'd be set!
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  • Troubleshooting Curt Voyager Brake Controller Not Functioning on 2018 Ram 1500
  • The issue is that the newer Ram trucks use a different style of brake signal that the Voyager you have is not capable of interpretting. Not every brake controller can be used on your truck for this reason and that's why yours can't tell that you are applying the brakes. You'll have to go to a controller from Curt that can be used on your truck like the Triflex # C51140 which is a proportional controller that would work well.
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  • Brake Controller Recommendation for a 2003 Ford Ranger
  • Does your 2003 Ford Ranger already have a 7-Way trailer connector? If not then to install a brake controller you will need to also install # ETBC7. If you do already have a 7-Way connector you will just need # 5506. For a brake controller I recommend the Draw-Tite I-Command # 5535. This is a "nothing fancy" proportional brake controller that will be great for your application. Proportional controllers like this will apply the trailer brakes in proportion to how much the tow vehicle is
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  • Installing the Curt TriFlex Trailer Brake Controller on a 2017 Chevrolet Colorado
  • I am having a hard time trying to understand your problem so bear with me here but it sounds like you are trying to install the Curt TriFlex Trailer Brake Controller part # C51140 on your 2017 Chevrolet Colorado with the Universal Wiring Adapter part # C51515. If that is the case then you are off to a great start as this is the correct harness for your Colorado. If your Colorado came with a factory 7-way then the wires you need to attach the harness to are already ran underneath the
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  • Recommended Brake Controller Wiring For 2017 Hyundai Santa Fe
  • There is no brake controller harness on your 2017 Santa Fe so it will require some hardwiring. First, you will need part # ETBC7. This plugs into the 4-way connector on your Santa Fe. You will then need to run the additional wires to complete the installation of the brake controller. I have attached a drawing that shows how the wiring is run for the # ETBC7 and the brake controller. The Curt TriFlex Brake Controller, part # C51140 is a proportional controller that will apply the
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  • Troubleshooting Curt TriFlex Brake Controller Not Showing Activation
  • On your Curt TriFlex Trailer Brake Controller # C51140, the decimal point as you put it is standby mode with no trailer connected. The blank screen is also standby mode and that screen is what is seen when simply starting the vehicle, but that screen should illuminate when you press the manual override or show the decimal point when you hit the brake pedal only while moving since it is a proportional controller. If it does not operate under those criteria, then you will need to have the
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  • Curt Triflex Brake Controller Always On Installed in a 2006 Volkswagen Touareg
  • Installation of a brake controller on a 2006 Volkswagen Touareg is a little more complicated than on many other vehicles. It requires some special parts from Volkswagen and you will likely need a 12 volt normally open relay to avoid erratic displays and trailer braking problems. I have included a link to a help article detailing the process. It is critical that it is followed exactly. I know this method works with Tekonsha controllers like the P2 # 90885 and P3 # 90195. I cannot confirm
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  • Could Curt Triflex Brake Controller Drain Truck Battery
  • Brake controllers like the Triflex part # C51140 will have an indicator light that will stay on for several minutes after the vehicle has stopped running. It eventually will go into sleep mode after a period of time. That indicator draws such a low amount that your battery would die from inactivity before it would drain it. It is most likely coincidence that you installed the controller recently. I'd take the truck to a local auto parts store to have the battery and charging system tested.
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  • Troubleshooting Curt TriFlex Brake Controller
  • If your Curt TriFlex Trailer Brake Controller # C51140 is just showing R then most likely you will need to recalibrate the controller. To do this, you can unplug and then plug back in the connector on your trailer. You will know it's recalibrated if ".." appears on the screen.
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  • 7-Way Installation Kit to Install Curt TriFlex Brake Controller in 2017 Audi Q5
  • So far so good but you need one more thing in order to install the Curt TriFlex Trailer Brake Controller # C51140 with Adapter # C51515 in your 2017 Audi Q5. Now that you have the 4-way # 119250KIT installed you will need to add the Universal Installation Kit for Trailer Brake Controller # ETBC7. This is going to give you the 7-way connector, circuit breakers and rest of the hardware needed to complete your brake controller installation. I have added links to a pair of help articles
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  • Troubleshooting Curt Brake Controller Installation in 2007 GMC Sierra New Body Style
  • First I suggest making sure you are testing the brake circuit pin on your Sierra's 7-way trailer socket. If you refer to the linked photo of a trailer connector you will note the brake controller's output is carried on the pin at the 5:00 position; the ground is at the 7:00 position. If you happened to test the 12V auxiliary power circuit, carried on the pin at the 2:00 position, it will have power at all times. I see that you purchased Curt Universal Wiring Adapter # C51515 which
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  • Adapter for Curt Venture Brake Controller on VW Touareg
  • In order to use the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515 with your Curt Venturer # C51110 brake controller, you will need additional parts from your Volkswagen dealer. Please see the attached help article on installing a brake controller in 2005 and up Volkswagen Touareg's. It states in part: "To install a brake control on a 2005-current Volkswagen Touareg or Porsche Cayenne using the factory brake control connector, you will need to assemble a brake
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  • When Does Brake Output Circuit of Vehicle 7-Way Have Voltage
  • The brake output circuit on a 7-way (5:00 pin) will only have as much voltage on it as the brake controller is sending. Typically this going to depend on the amount of gain selected on the controller and other factors like brake controller style and ramp up speed of the controller. The only time the circuit would have voltage without the brake pedal being applied would be if you had the manual override lever of the controller slid. I attached a couple help articles on brake controllers
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  • Brake Controller and Install Harness Recommendation for a 2006 Jeep Commander
  • The correct Curt brake controller install harness you will need for your 2006 Jeep Commander is the part # C51515 that you referenced. I would recommend you go with a proportional brake controller with it like the Curt Triflex part # C51140 as it will sense the amount of braking you are applying with your vehicle and will provide a proportional amount of braking power to the trailer. Some models will require a wiring kit to run wire to the battery. This may require drilling a hole
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  • Brake Controller Recommendation for a 2012 Mercedes GL450
  • In order to install a trailer brake controller on your 2012 Mercedes GL450 it will require hardwiring in the controller unless the Mercedes dealer has a wiring harness specific for a brake controller and your vehicle. If they do then you will need to wire in the controller to the Mercedes harness by function. On a brake controller, the wire functions are as follows: White is ground Black is 12 volt power Blue is output to the trailer brakes Red is input from the brake switch On
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  • Brake Control Harness # 51515 Installation Process in 2008 and 2013 Chevrolet Silverados
  • The Curt Brake Controller Harness you referenced, part # C51515, can be used for both the 2008 and 2013 model years of the Chevrolet Silverado since it is a universal-fit harness. For your 2013 Silverado you will want to follow the procedure outlined in the linked article. Please refer to the photo provided which shows the vehicle tow package wiring that can be found under the dash. You will connect these wires to the leads on the Curt harness as per the article, using butt connectors
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  • How to Install the Curt Wiring adapter # C51515 on a 2008 Chevrolet Silverado
  • To install the Curt Wiring adapter # C51515 in your 2008 Chevrolet Silverado you will need to hardwire it under the dash. To be sure that the wire bundle you found under the dash is the correct set of wires I would check the white tag for any indication as to what each wire is for. If none of them have labeling then it would be best to test their functions with a circuit tester like part # PTW2979. You will then connect the following wires from the Curt adapter to the following functions: Blue
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  • White Ground Wire Is Taped To Orange Wire 2009 GMC Sierra 1500 Brake Controller Install
  • You want to use the white wire in your photo for the ground. The other orange wire is the CHMSL circuit which stands for center high mount stop light wire. It is not used by a brake controller so you can tape it up and stow it out of the way. You will need 4 wires to install the brake controller, 12 volt power (red and black in your photo), trailer brake output (solid blue in your photo), stoplight circuit (light blue with stripe in your photo) and ground (white).
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  • Custom Wiring Adapter for 2012 Chevy Silverado Curt Brake Controller
  • If you are looking for the custom adapter for the Curt Reflex Trailer Brake Controller # C51130, you will need the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515. Unfortunately, no factory plug is present under the dash on your truck, but the needed wires are already run. You will connect the brake controller wiring with the vehicle wiring already present under the dash. It is a two foot long wire. These are twelve gauge wires with a protective coating to prevent
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  • Installation of Curt Brake Controller on 2009 GMC Sierra 1500
  • When it comes to installing a brake controller like the Curt # C51170 using the adapter # C51515, the color of the wiring isn't always a reliable way to determine the functioning of a wire, so you'll likely want to test the functions using a circuit tester like the # PTW2993. In some cases the colors will match up, but it's not always the case. As long as you're able to match up the correct wires under the dash to the adapter, you'll be able to use the brake controller without issue. We
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  • Troubleshooting Brake Controller Not Allowing Truck To Start
  • For your 2014 Chevy Suburban, no plug is present under the dash, but the needed wires are already run. You will connect the brake controller wiring with the vehicle wiring already present under the dash using the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515. It seems the 2007 to 2013 brake controller wiring was carried over into 2014 for your vehicle. I've attached and article to assist. The issue you are experiencing is most likely because you have a plug
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  • Troubleshooting Curt Venturer Brake Controller Installed on 2011 Dodge Ram 1500 Pickup
  • Getting a single green LED on the display indicates that there's no trailer connected. Since you're getting this with the trailer connected, it would seem to indicate that the brake controller isn't 'reading' the trailer for some reason. The most common reason for this to happen would be a dirty, corroded or damaged connector on the vehicle or the trailer. Examine the trailer connectors, and ensure everything is clean. If you see any white or green corrosion on the pins or sockets of the
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  • Wiring Adapter for Curt Electric Brake Controller on 2016 Toyota Tacoma
  • We do offer the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515. This adapter will connect with the plug on the back of the Curt electric brake controller on one end and the other end will allow you to hardwire install the brake controller. If you need to add a 7-Way to your tow vehicle, the # C51515 adapter will work well with the Universal Installation Kit for Electric Trailer Brake Controller # ETBC7. The instructions for this hardwire installation are linked
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Info for these parts were:

Edited by:
Leah B
Expert Research:
Mike L
Expert Research:
Michael H
Expert Research:
Jameson C
Expert Research:
Adam R
Video by:
Andrew K
Video by:
Joshua S
Written by:
Lindsey S
Installed by:
Jeff D
Test Fit:
Nicholas E
Test Fit:
Shane T
Test Fit:
Brent H
Test Fit:
David F
Test Fit:
Ryan G
Video Edited:
Andrew L
Video Edited:
Dustin K
Video Edited:
Sue W
Video Edited:
Chris R
Updated by:
Sarah W
Updated by:
Kristina F
Updated by:
Isabelle B

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