1. Trailer Brake Controller
  2. Curt
  3. Electric
  4. Electric over Hydraulic
  5. Proportional Controller
  6. Under-Dash Box
Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional

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

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Trailer Brake Controller
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Curt Electric,Electric over Hydraulic Trailer Brake Controller - C51140
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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. Lowest Prices for the best trailer brake controller from Curt. Curt TriFlex Trailer Brake Controller - 1 to 4 Axles - Proportional part number C51140 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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  • Reviews (346)
  • Q & A (318)
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  • Why etrailer?

Curt Trailer Brake Controller

  • Curt
  • Electric
  • Electric over Hydraulic
  • Proportional Controller
  • Under-Dash Box
  • Automatic Leveling
  • Up to 4 Axles
  • Dash Mount
  • 90 Degrees

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

Item # C51140

Installation Details C51140 Installation instructions


California residents: click here



Customer Reviews

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

Average Customer Rating:  4.7 out of 5 stars   (346 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.

- C51140
by:

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



- C51140
by:

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:

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:

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:

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
$8.49
. 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
$65.51
. 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
$32.91
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
$109.42
and not the part # 5506
Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers
$65.51
. 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
$20.13
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:

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:

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:

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:

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:

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:

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:

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:

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:

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



- C51140
by:

Works very well ! 573332



- C51140
by:

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:

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:

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:

Great price, great product, perfect fit and fast delivery. 100 percent satisfied. 897589



- C51140
by:

896779



- C51140
by:

893373



- C51140
by:

Simple plug and play hook up. Easy adjustment as well. 891765



- C51140
by:

I installed the trailer brake controller on our Nissan Pathfinder and it worked as advertised. The hardest part of the installation was finding the factory-installed connector cable under the dash. Help videos and pictures were invaluable. The setup procedure on the quick reference guide worked perfectly. Never having installed a brake controller, I was a little leery of my ability to install it successfully, but the helpful instructions and videos made it easy. 887114



- C51140
by:

Was just able to install controller, everything went really smooth, works great, thank you for the quick delivery as always. 884006



- C51140
by: 09/18/2020

Great product! 882822


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Ask the Experts about this Curt 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...
  • 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.
    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...
  • 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...
  • 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...
  • 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.
    view full answer...
  • 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...
    view full answer...
  • Troubleshooting Curt Triflex Brake Controller that Flashes that a Trailer is Connected
    The Triflex # C51140 sometimes does need to be reset occasionally. Try unplugging it and plugging it back in after a few seconds and it should work again. Otherwise you have a short between the black wire and the red wire and your controller therefore is thinking you have the brakes all the time. If you can check the connections between the two circuits there might be exposed wire between the two and that's why you are seeing the issue. I also attached a help article on troubleshooting...
    view full answer...
  • 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!
    view full answer...
  • 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.
    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...
  • Troubleshooting Curt Triflex Brake Controller Showing OL Code on Display
    The Curt Triflex brake controller is known to have more problems than other brake controllers so I would not rule out the problem being the controller. Testing the brake controller is fairly easy. Sever the blue brake output wire near the brake controller leaving enough room to reconnect it and then apply the manual slide. Using a circuit tester like the Quickee Tester, part # PTW2993, you should get output to the controller side of the wire you severed. If the manual slide activates...
    view full answer...
  • 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...
  • 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...
  • Troubleshooting Curt Triflex Brake Controller With Dashes Displaying
    What is happening with your Curt TriFlex Trailer Brake Controller # C51140 is that you have a poor ground connection most likely. I took a look at the manual for this controller and with your display showing two dashes the issue was either a battery that was not providing enough power - which we know based on the 12 volts you were getting not to be the case - or you had a poor ground, which is the leading cause of all wiring problems. So you need to double and triple check you have a good...
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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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  • 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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  • 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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  • 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...
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  • How to Install a Brake Controller on a 2012 Volkswagen Touareg
    There isn't a plug in style connector to install a brake controller on a 2012 Volkswagen Touareg. If your Touareg came with a factory 7-Way trailer connector there is a fairly easy way to install a controller. Take a look at the help article I have linked to the right. It explains what you will need to do and the wire functions for installation of a brake controller. The article also mentions needed a relay for certain brake controllers but that should not be needed for a 2012 model. For...
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  • Curt TriFlex Trailer Brake Controller A.E. Error Code Troubleshooting
    The operating instructions for the Curt Triflex brake controller # C51140, which are linked for you, indicate on page 19 that if the unit displays the error code A.E. this indicates an internal fault with the controller's accelerometer. This is not a serviceable problem and the unit should be replaced or referred to Curt for warranty service under the terms of the limited lifetime warranty.
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  • LED Display of Curt TriFlex # C51140 Brake Controller Remains Illuminated When Vehicle is Shut Off
    Because it's connected to a constant 12-volt power source, the LED you mention will remain illuminated after the vehicle is shut off. This is normal, and does not indicate a problem of any kind. After 15 or so minutes of inactivity, the brake controller goes into a 'sleep' mode, and will reactivate next time the brake pedal is pressed. The LED only draws a few milliamps of power, which would only drain the battery if the vehicle sat unused for months. You could certainly unplug the controller...
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  • How To Install A Brake Controller On A 2015 Chevrolet Traverse
    In order to install a brake controller like the Curt TriFlex Trailer Brake Controller part # C51140 on your 2015 Chevrolet Traverse, you first want to get a universal wiring harness like the Universal Wiring Adapter for Curt Trailer Brake Controllers part # C51515 and a set of wire connectors such as the Deka Heat Shrink Butt Connector part # DW05744-10. You can then begin the installation by attaching the wires from the brake controller to the pre-ran wiring harness on your vehicle....
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  • Trailer Brakes Only Work with Manual Override and Not With Brake Pedal on 2009 Dodge Ram 1500
    Nine times out of ten, it is not the brake controller that is causing the problem. But in this case, with the output not changing when you step on the brake pedal, there does seem to be an issue. Typically when there is no braking with the brake pedal that indicates a connection problem with the red wire. Test for power on the red wire using a circuit tester such as # PTW2992. It should have power when the pedal is pressed. If it does not have power when the pedal is pressed check the...
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  • What Does Sensitivity/Boost Setting of Curt TriFlex Brake Controller Refer To
    The Curt Triflex Brake Controller part # C51140 that you referenced has 9 different sensitivity settings so that you can adjust how aggresive you want the inertia sensor to react to deceleration. Since not all trailer brakes are as sensitive as others this allows you to tailor the braking to the trailer. So basically the higher the sensitivity the harder the brakes will apply with the same level of deceleration. This is also known as the "boost" setting as well.
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