Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional
Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In

Part Numbers: C51140,C51436

Retail:$143.79

Our Price: $107.67

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C51140 - Digital Display Curt Brake Controller
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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



Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In
part number: C51436

Install your Curt electric trailer brake controller quickly and easily with this custom wiring adapter. Simply plug one end of the adapter into your brake controller and then plug the other end into the built-in port behind your vehicle's dash.

Features:

  • Plug-in wiring adapter allows for quick, simple installation of your electric trailer brake controller
  • No cutting or splicing required
    • Custom connector end plugs into the built-in port behind the dash of your vehicle
    • Other end plugs into the back of your electric brake controller
  • Compatible with time-delayed and proportional brake controllers from Curt
    • Brake controller must have built-in plug for adapter to connect - will not work on controllers with pigtail wiring harnesses
  • 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. When this is done, a port is installed at your dash so that you can easily plug in a brake controller.


This adapter plugs into the port on your vehicle's built-in brake control wiring harness. For most applications, this harness is located behind the dash.


No hardwiring is required to install this adapter. After you plug it into the factory port, you simply plug the other end of the adapter directly into your electric trailer brake controller. Because there are no wires to connect, installation is not permanent. You can unplug and remove your brake controller at any time to transfer it to another vehicle or securely stow it away.



51436 Curt Quick Plug Brake Control Adaptor Harness



California residents: click here





Customer Reviews

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

Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In - C51436

Average Customer Rating:  4.8 out of 5 stars   (288 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. Install your Curt electric trailer brake controller quickly and easily with this custom wiring adapter. Simply plug one end of the adapter into your brake controller and then plug the other end into the built-in port behind your vehicle's dash.

- C51140
by: Jon02/11/2019

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



- C51140
by: Rick10/10/2018

Works very well ! 573332



- C51140
by: Bill02/26/2019

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



- 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: 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: 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



- 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



- 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: 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
$7.95
. 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
$39.83
. 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
$24.86
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
$58.20
and not the part # 5506
Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers
$39.83
. 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
$19.95
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: Robert A.04/21/2017

The unit with the matching installation cable was easy to install once I found the factory installed plug-in port on my 07' Dodge Quad Cab. The videos didn't have my truck model and I had to go to the Curt mfg website to find a picture of the the location of the port. I have not hooked up the truck with the trailer yet to test and adjust the brakes but the controller installation and functionality test was very easy to accomplish and went smoothly with the instructions provided. 370441



- 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: 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: 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: 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: 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: Bill Y.09/28/2015

I installed this unit, hooked up my travel trailer and had it all calibrated and ready to hit the road in less than an hour. Took a 300 mile trip a few days later and the unit was flawless. Forget the old time delayed units, this is the way to go. Also, get the pigtail that is designed for your particular vehicle, it makes installation a snap (plug in to your vehicles available plugin and into the back of this unit) couldn't be simpler. Very satisfied with the unit and with e-trailer.com. Great products, great service. 228079


Comments

Still satisfied, works great.

Bill Y - 09/27/2016

21272

- C51140
by: Joe R04/24/2014

placed into my 2014 RAM 1500 put it in place only took about a half hour with the right harness. 127226


Comments

Just curious, how much weight have you towed with the controller and how well did it perform? What setting did you run?

-- comment by: John P - 09/26/2015

15232
Comments

Hi John I have a ram 1500 V6 . My camper is 19 ft about 4300 LBSI have the sensitivity setting at L7 and the thumbwheel set around 20 to 25 .. If every thing reads ok from the codes .the setting are easy to test with a short drive .Adjust your settings to your liking. after setting for awhile like over the winter or pulling out from a seasonal site you may need to run little heaver on the break for a short time . It has plenty of power to stop you with just the trailer brakes .

-- comment by: Joe R - 10/13/2015

15525

- 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: Ryan R04/12/2015

Installation was easy. Product works well. The power and sensitivity adjustments are very useful. 184853


Comments

Everything is still working fine.Thanks for Asking

Ryan R - 04/21/2016

17533

- C51140
by: Jared S.10/12/2017

The trailer brake worked out very well. Installation was a little difficult for someone with no experience, but the videos on etrailer were great. My only issue would be that I only had about a foot of spare cable left at the end of the install, a few more feet would have helped me feel more comfortable. Otherwise, great product and site. Having all the right equipment and videos appropriate for my Jeep were essential. 442038



- 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



- C51436
by: Tommy J.01/31/2014
2014 Ford F-150

Adapted Curt brake controller for my 2014 Ford F150 STX without any problems. Just find your Ford brake control connector behind the coin slot on the left side of the dash and plug it in. 115344


Comments

After a year of using the Curt brake controller it has been by far the best one of several I have used and installed. i highly recommend the controller.

Tommy J - 01/31/2015

9143

- C51140
by: Doug S09/15/2013

To be honest, haven't installed yet. Have to run wiring in 2 trucks as neither has factory wiring. I want mounting to be not noticeable if I sell either vehicle. Based on reviews, and having my hands on it and the printed directions I believe it will fit my greatly fit my needs. I have a one month plus to get one vehicle ready for a road trip. LOL, I like to plan ahead. Will write more when I get working. 99999



- C51140
by: OEM09/24/2017

The screws for the bracket did not fit into the plastic bushings in the bracket. I have got hooked this up to a trailer with brakes, yet, but everything else seems to work, including the adapter for my Silvy1500. Note that this review bears no negativity on etrailer, but he manufacturer of the brake controller. Stop letting China manufacture our goods and get better product reviews. I have had good experiences with etrailer.com, they always ship fast and deliver quality installation guides. Kudos to them! 435970



- C51140
by: Mark from Pa10/13/2013

Was very easy to install. Shipped out same day. I'm very particular so install took longer than necessary about 20 minutes. I don't like having extra holes or things mounted crooked on my truck. Used it same day I installed it to haul our livestock trailer. Worked great braking was very smooth. Can't say it is better or worse than any other controller but I am happy with this one. 103662


Comments

mark question for you is breaking between having the trailer load with livestock to empty is there lots of adjustment or no problems

-- comment by: mike - 04/10/2015

10724

- C51140
by: Greg C.08/04/2015

After talking at length (at least 15 minutes) to the rep on the phone, I choose the Curt TriFlex controller for my 2015 Silverado. It happens to be the same unit sold on Chevy's website (but cheaper on etrailor). The sales person was awesome! She wanted to be sure I got the right one, not trying to upsell me on something I didn't need. Just as she promised, it plugged right in under the dash and I even used an existing screw to mount the bracket. A 15minute install!!! I will shop here again. 216669



- C51140
by: Larry H08/23/2017

I haven't used it yet, because I cannot seem to get it wired correctly. It had good reviews and my son purchased this unit for his new truck and trailer about 6 months ago. He personally recommended it for me. But I have yet to see a video by etrailer or anyone else showing exactly where the brake light wire is under the dash for my '95 Suburban. I have paid 2 techs to wire the red wire.....wrong. 424375


Comments

Larry, after reviewing your order notes today, I see that your 3rd mechanic was able to find the wire. Some models do have the brake blue and hot lead orange or red wires already ran from under the hood to the end of the drivers side frame rail. However, as you know, these wires are hard to access and additional wire will still be needed. Part # ETBC7
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
$58.20
is still recommended.

-- Laura E - 08/30/2017

27739

- C51140
by: Kevin L09/12/2013

So far , so good . Install took a whole 5 minutes and the overall size is easily dealt with in my Tacoma . Nice to have the led display - not too bright but easy to read and understand diagnostics and output levels . The compact size is a real bonus and it's controls are easy to understand , no complaints at all . Best is it's bracket system - screw holes to mount to the truck side are outside of the main bracket dimensions which allows a lot easier install - great intuitive design instead of trying to position , remove controller and mark holes . I was able to actually drill right past the controller in-place and install the screws , dead simple . Kudos to Curt for a great design/product . 99562



- C51140
by: Lee A07/23/2013

I received my Curt triflex brake control in less than a week from ordering on line. It was so easy to put in and set up. I couldn't believe it. Just plug and play. 91176


Comments

It didnt. It would not adequately slow down or stop my 34 fifth wheel. I pulled it out and installed a Prodigy. The Prodigy works just fine.

Lee A - 01/21/2015

8796

- C51140
by: Steven08/29/2018

I wasn't very pleased with this brake controller. It seemed to frequently require resetting, which involved stopping, getting out and unplugging/replugging the brake cable. I was never able to get a good understanding of the controls either - there was a dial for gain and a slider for "aggressiveness" (huh?). Also, after using it for about 10 months, I thought the brakes on my trailer needed replacing - it would brake some, but not much. About that time I bought a new truck with built-in brake controller and the trailer brakes worked great again. Had to be due to the controller... 559619



- C51140
by: Robert07/15/2018

Item is smaller and lighter than expected. Easily mounted using existing dash screw. Pigtail wire kit that was also ordered here made installation a snap. I like the display and the ability to manually apply trailer brakes and increase braking force on the fly. Less than a 5 minutes install. Installed only, haven’t used it yet. Will have to update later. Rig is 2007 Dodge Ram 2500 4X4 CTD. 542058



- C51140
by: Bryan07/15/2018

This was my first brake controller. Installation took me about 40 minutes. Having the truck prewired means its as simple as plug and play. As soon as I powered it up it worked, and calibration once I was hooked up to a trailer took just a few minutes. So far I'm pleased. I'm still working on the right settings but I would definitely recommend this unit. Also staff at Etrailer were very helpful. The first controller I ordered had the cable out of stock. They emailed me right away and helped me pick one out that was in stock and arrange the two day shipping I needed. This was on a Friday evening, so many places would have waited until Monday to let me know. 541910



- C51140
by: Troy06/21/2019

Great product and easy to install with the pigtail adapter. 661109



- C51140
by: Gregg06/06/2019

I like the installation photos provided in the Q&A section. Fast shipping. 654104



- C51140
by: Daryn05/28/2019

Installed in my 2012 Chevy Tahoe in about 20 minutes. Put it to work 15 minutes later and everyting performed perfectly. Hauling an 8 x 16 tandem. Controls are a piece of cake, set-up is a breeze. 647630



- C51140
by: Good Product05/15/2019

This product is great and does a fine job...just make sure you mount it correctly. I wanted to mount it vertically instead of horizontally and it WON'T function correctly. I should have gone with a regular version instead of a fancy sensing version of brake controller...my bad! 642181


Comments

Like most all proportional brake controllers, the Curt Triflex needs to be mounted pointed in the direction of travel, level on a side to side plane as described in the instructions linked above. Older time-delayed controllers are indeed more forgiving about how theyre attached to the vehicle, but the braking performance gained from a proportional controller is far superior to that of time-delayed controllers.

-- Mike L - 05/16/2019

55331

- C51140
by: John R.05/11/2019

Worked for a couple months and broke. Save yourself the hassle and just buy the Curt brake controllers that are made in the USA. They costs a little more up front, but the higher quality of the design and components is worth it. 640867



- C51140
by: Charles05/03/2019

This brake controller works well. On long trips adjusting is necessary and the Curt TriFlex makes it easy. Search for your application including adapter cable. ETrailer Customer Service is excellent. 637556



- C51140
by: Larissa05/03/2019

Bought this brake controller for my old 1985 F350. I was still using the old style brake controller hooked up to my brake fluid lines. Was able to easily pull the old controller and use the same holes under my dash to bolt the new electric one in, had to do some electrical splicing of course... I typically haul a 3 horse trailer w/living quarters, but also a 3 horse bumper pull and equipment trailers. Brake controller works great on my big and small trailers. Settings are easy to configure and I have no doubt my brake controller will work when hauling down the road. 637033



- C51140
by: Marc04/27/2019

Installed this brake controller last weekend. etrailer has helpful videos that also include associated products with part numbers. Watching the video and checking other references confirmed I needed the wiring harness, too. So I ordered both and it made the install go smoothly. 635466



- C51140
by: Michel04/22/2019

Installation was easy with Adapter cable and Controller which I installed on top of dash board cover and required only one hole to be drilled. Installation location allows for easy access to adjust settings, apply the trailer brakes alone and see the display. Tough part was locating the 2010 Ford F53, Wennibago, Vista, OEM connector which was out of sight. Remove the dash board cover, which was easy, then look for the big harness (see pictures) and the smaller cable which splits away from it. None of the literature explained that the connector is gray for six pins although only for pins are in the connector. Once found, just plug things together and it all works. 634129



- C51140
by: John B.04/15/2019

Easy to install, works perfectly, no pr oblems! 628871



- C51140
by: David03/27/2019

Works well, was easy to install in my 2011 Silverado. The sensitivity wheel and power slide on the top and side of the controller respectively are pretty sensitive but nothing that causes issues. Mounts firm and feels solid. Comes with a little card that you can keep in your glovebox as sort of a cheat sheet to all the different meanings of codes it will display which is useful. 614606



- C51140
by: Chris03/27/2019

Great quality and I had an issue withUPS called and and they fixed it immediately. Thank you again. 614576



- C51140
by: Dave03/27/2019

Easy to install, a couple of screws and plugged right into the Jeep with the connector wire also purchased through etrailer. Easy to set up and adjust. I have had to reset it a couple of times, but that only requires unplugging it and plugging it back in. 614485



- C51140
by: Delbert03/04/2019

Works very well. Easy installation 610171



- C51436
by: Joshua03/02/2019
2013 Ford Flex

Made the installation in my 2013 Ford Flex Limited a breeze! 609682



- C51436
by: Bob02/19/2019

Direct plug in with the truck. 606349



- C51140
by: Ian T02/08/2019

Bought this for my 2016 silverado, and it works fine . Its really hard to dial in an exact "L" number with the side slider (it feels loose and is super sensitive), but I find that it doesn't really matter much even when towing a ~5000lb trailer. Close enough seems good enough for me. Setup was easy (plug and play), and i just mounted mine to a thin piece of wood and used super strong velcro on the wood and my under dash to avoid drilling holes in my truck. Wire loom or electric tape to tidy the wires and you're all set. Nothing fancy, and it does the job. 603441



- C51436
by: Todd12/03/2018

Plug and play, works as expected. 588143


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Ask the Experts about this Brake Controller


  • 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
    view full answer...

  • Correct Wiring Harness for the Curt Triflex Brake Controller
  • The Curt Triflex brake controller # C51140 is an excellent choice when adding a brake controller to your vehicle. This brake controller activates trailer brakes in proportion to your vehicle's braking action, automatically adjusts trailer's braking based on deceleration of tow vehicle, and activates immediately with no pausing like with time-delayed brake controllers. But when trying to find the correct wiring harness to install it into a 2008 GMC Denali XL, the answer is the Universal
    view full answer...

  • Constant Voltage on 12V and Brake Controller Output Wire with Curt TriFlex Trailer Brake Controller
  • When testing the wire functions after installing the Curt TriFlex Trailer Brake Controller # C51140 and Wiring Harness # C51515 in your 2014 Toyota Sienna, it is normal for both the 12V and brake lights on a tester like # TR20117 to light up without actually activating the brakes. This is because the brake controller sends out a small trace current to look for a completed circuit. I have attached a demonstration video on a similar 7 Way Trailer Connector Vehicle Tester # TR20117 that shows
    view full answer...

  • Are the Curt TriFlex # C51140 and Curt Adapter # C51453 a Fit for a 2014 Ram 1500 4WD 5.7 Hemi
  • You have exactly what you need for installing a brake controller in your 2014 Ram 1500. Brake controllers, like your Curt TriFlex # C51140, aren't necessarily vehicle specific, but the plug-in wiring adapter harnesses are. The correct one for your 1500 is the Curt # C51453 that you referenced. This will plug into the port under your driver side dash and allow you to easily install and remove the controller when needed.
    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...

  • Where Is Brake Controller Install Port on 2017 Ram 1500
  • To install a Curt brake controller like the part # C51140 in a 2017 Ram 1500 the correct install harness is the part # C51458. If you check out the install video I attached below you'll see exactly how a similar brake controller installs on a 2017 Ram 1500 like what you have. Fast forward to the 2:30 section of the video to see where the port is found.
    view full answer...

  • 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
    view full answer...

  • Brake Controller Install Harness for Installing Curt Triflex in a 2016 Ram 1500
  • To install the Curt Triflex brake controller part # C51140 in your 2016 Ram Bighorn 1500 all you need is the correct install harness, part # C51458. The truck pigtail is right above where your right foot would be covered in a foam tape.
    view full answer...

  • Troubleshooting Curt Triflex Brake Controller that Stopped Working with Brakes
  • First thing to check is to see if your truck's third brake light is still working when you hit the brakes. When the fuse for that circuit goes on GM trucks like your 2014 model it will prevent the brake controller from activating when the brakes are applied. Next check to see if there's voltage on the red wire of the brake controller when the brakes are applied. If so, and the controller still won't activate with the pedal it has an internal problem and would need to be replaced. Curt
    view full answer...

  • Is there a Brake Controller Wiring Harness for a 2008 Mercedes GL550
  • There isn't an aftermarket brake controller wiring harness that will fit your 2008 Mercedes GL550 so you have a couple of options. First you can see if there is an adapter from a Mercedes dealer with one end that plugs into the port under the dash and the other end with just wires. Then you could wire the controller to that adapter harness. The other option is to determine the functions of the pins in that port using a circuit tester such as # 40376 or a meter if you have one. One pin
    view full answer...

  • Parts Needed to Install a Trailer Brake Controller on a 2009 Audi Q7
  • If your 2009 Audi Q7 does not have a factory trailer connector at the rear of the vehicle then you will need to install both the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit part # 119250KIT and the Universal Installation Kit for Trailer Brake Controller part # ETBC7 in order for a brake controller to work. Trailer brake controllers are universal and can be adapted to fit any vehicle with the correct wiring harness. The correct wiring
    view full answer...

  • Can Curt TriFlex Trailer Brake Controller # C51140 Be Temporarily Disabled When Backing Up
  • I did some research on this controller for your 2006 Chevrolet Silverado, and there are no features available that will turn the Curt TriFlex Brake Controller, part # C51140 off. The best way to temporarily disable the controller when you intend to back up is to unplug the trailer. If you were to unplug the controller, it would have to be reset when it is plugged back in. I spoke with my contact at Curt and they strongly advised against doing this because if someone failed to reconnect
    view full answer...

  • Troubleshooting Curt TriFlex Brake Controller that Flashes L.6
  • L.6 is the sensitivity setting your Curt Triflex # C51140 currently has. It has a sensitivity range between L.1 through L.9. Since Curt controllers are known to be a bit buggy this isn't super surprising that you are seeing this. What Curt would recommend is to unplug the controller for a few seconds to let it reset and then plug it back in. Normally this takes care of strange behavior like this.
    view full answer...

  • Location of 7-Way Tow Package Wires on a 2005 Chevy Tahoe to Install a Brake Controller
  • If your 2005 Chevy Tahoe did not come with a factory installed 7-Way trailer connector then you will need to add one using # 30955 which plugs into a connector located above the spare tire under the vehicle. I have included a picture that shows what it looks like for you. If your Tahoe doesn't have that round connector above the spare tire then there would be a wire bundle instead in the same location. And if your Tahoe came with a factory 7-Way then there is no other connection you
    view full answer...

  • Curt Triflex Trailer Brake Controller Shows Power All the Time on Blue Wire
  • You should only be seeing 12 volts on the blue wire on the brake controller, # C51140, when the manual override is used. If there is constant power all the time then there is either something that is miswired or a problem inside the controller and it will need to be replaced. Brake controllers do send back a minimum amount of voltage to check for a connected trailer but it should not be enough to activate the brakes. In the truck cab you will need to sever the blue wire several inches
    view full answer...

  • Troubleshooting Two Dashes on Curt TriFlex Brake Controller Display
  • On the Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional # C51140 the double dash display means you have a power issue. It can be that you are not getting 12V to the controller, or it can mean your ground connection is bad. You will want to check your brake controller wiring. White is ground and black is 12V power. You can use a circuit tester like # PTW2993 to test these wires.
    view full answer...

  • Curt Trailer Brake Controller Only Works with Manual Override on a 2014 Toyota Tundra
  • When a brake controller works with the manual lever but not with the brake pedal that usually indicates a problem on the red wire. The red wire is the input wire that tells the controller you are stepping on the brake pedal. The most common issue with the red wire is actually a blow stop light or CHMSL fuse. Use the owners manual to find the stop light or CHMSL fuse to check it. You will also want to test the red wire using a circuit tester such as # ALL640595. With the brake pedal
    view full answer...

  • How Does Brake Controller Install in 1993 Chevy 4x4 Z71
  • The 1993 Chevy C/K trucks like yours do not have a factory pre-wired brake controller port so you'd have to hardwire the controller to your existing 7-way. For a wiring kit to install the brake controller to the 7-way you would want the Wiring Kit for 2 and 4 Brake Electric Brake Controllers # 5506. This will provide the power source and ground for the wiring for the brake controller. You will need to test the wires from the brake pedal switch of your vehicle to find a circuit that
    view full answer...

  • 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
    view full answer...

  • Curt Triflex Brake Controller Displays 05 and Trailer Brakes Not Working with Brake Pedal
  • On Curt brake controller # C51140 there is a 20 display so if the display is upside down is would look like 02 or 05. That message either indicates that a trailer is connected and the brakes are activated or, if it is flashing, that means it is in output adjustment mode waiting for the power output to be adjusted. Try adjusting the power to 2.1 to see if it displays 1.2 or 1.5 and if so then the display is showing upside down. I also recommend cleaning the vehicle and trailer side connectors
    view full answer...

  • Hardwiring in a 7-Way Trailer Connector and Brake Controller on a 2018 Ford F-150 w/Factory 4-Way
  • I did some checking and right now, in order to add a 7-Way trailer connector to your 2018 Ford F-150, you will need to use our hardwire kit # ETBC7. The factory brake controller wiring harness might be in place but if it is for sure and if that means you can install the Ford brake controller I cannot answer. I am sure you can though because I know in other Ford F-150s you can. Or you could install an aftermarket brake controller using wiring harness # 22292 and a Tekonsha brake controller.
    view full answer...

  • Which Curt Brake Controller Adapter Fits a 2015 Ford F-150
  • The Curt adapter, part # C51436, fits your 2015 Ford F-150. It plugs into the factory connector under your truck's dash and fits most Curt brake controllers, like the Venturer part # C51110. I've linked a video of a controller being installed into a 2013 F-150 using the # C51436 adapter.
    view full answer...

Info for these parts were:

Test Fit:
Joe V
Edited by:
Leah B
Photos by:
Jackie C
Expert Research:
Michael L
Video by:
Andrew K
Written by:
Lindsey S
Expert Research:
Michael H
Installed by:
Jeff D
Expert Research:
Jameson C
Video Edited:
Joshua S
Test Fit:
Nicholas E
Video Edited:
Jacob T
Test Fit:
Rick A
Expert Research:
John H
Updated by:
Adele M
Video Edited:
Andrew L
Expert Research:
Adam R
Video Edited:
Kathleen M
Video by:
Dustin K
Test Fit:
Shane T
Expert Research:
Rachael H
Expert Research:
Jeffrey L
Video Edited:
Sue W
Test Fit:
Randy B
Video Edited:
Chris R
Updated by:
Sarah W
Updated by:
Amanda M
Video Edited:
Zach D
Test Fit:
Brent H
Test Fit:
Shane H
Updated by:
Kristina F

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