Curt Discovery Trailer Brake Controller - 1 to 4 Axles - Time Delayed
Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In

Part Numbers: C51120,C51436

Retail:$106.47

Our Price: $64.92

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C51120 - 360 Degrees Curt Time Delayed Controller
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Curt Discovery Trailer Brake Controller - 1 to 4 Axles - Time Delayed
part number: C51120

Electronic controller activates electric trailer brakes with a preset intensity when you apply the brakes in your vehicle. Power output and braking aggressiveness are easily adjustable. Includes easy-to-read digital display and manual override.

Features:

  • Brake controller activates trailer brakes with preset intensity
    • Signal is sent to trailer brakes when tow vehicle's brakes are activated
  • Adjustable, thumbwheel power output control lets you determine the amount of braking force
    • Set to maximum when you travel through hilly terrain with a fully loaded trailer
    • Back off the power output when you tow a lightweight trailer
  • Sync setting lets you adjust the aggressiveness with which the brakes are activated
    • Get full power output faster by moving slide-bar switch forward to increase activation speed
    • Achieve smoother braking by moving switch in opposite direction to supply power gradually
  • Easy-to-read digital display communicates brake force output, sync setting, and error codes
  • Self-diagnostics function monitors trailer connection and checks for shorts
  • Built-in, slide-bar manual override
  • Quick and easy installation
    • No need to mount level like proportional brake controllers
    • 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 brakes only
  • Limited lifetime warranty


Time-Delayed Braking

The Discovery applies your trailer's brakes when the brake pedal in your tow vehicle is engaged. Every time you apply the brakes in your vehicle, a signal is sent - via the brake switch - to the Discovery. The controller then sends power out to your trailer brakes to activate them with an intensity set by you, at a rate determined by you. Both the amount of braking power (output) and rate of application (sync) can be adjusted to suit your preference, the road conditions, type of trailer, and size of the load. To determine which levels are best for your application, you must test out your towing setup and choose what feels best.


A time-delay controller is so named because there is a delay between the time that you initially apply the brakes in your tow vehicle and the time that the controller reaches maximum power output. Unlike a proportional brake controller, which activates your trailer's brakes based on the deceleration of your tow vehicle, the Discovery sends power out in the same way, with the same gradual delay, no matter the braking situation. Although this delay always exists, it can be adjusted by changing the sync setting.


Built-In Controls for Adjustable Power

Curt Discovery Controls and Components

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

  1. Digital display
  2. Power output control
  3. Sync control
  4. Slide-bar manual override

Output Control

During the initial setup process, use the thumbwheel control on top of the Discovery 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. This setting ranges from 0 to 10, with 10 indicating maximum output.


Sync Setting

To adjust the aggressiveness of your trailer's braking action, use the slide-bar control on the side of the Discovery to change the sync setting. If you want to reach maximum power output faster, move the switch forward. To get smoother braking action, slide the switch backward, thus supplying power to the trailer brakes more gradually. You can alter the sync setting to suit your driving preferences or to improve handling based on changing road conditions or varied trailer loads. The digital display will only show the sync setting as you adjust it.


Quick, Simple Installation

Because inertia plays no role in the functioning of this controller, you do not have to mount the unit at any particular angle. As a result, mounting options are limitless, so long as you can still easily access the controller.


Installation of the Discovery requires that you either purchase a custom wiring adapter designed to plug into the controller or that you hardwire the controller directly into your vehicle. To hardwire the Discovery, you must remove the plug at the end of the integrated wiring harness.


Installation Accessories

For 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.



51120 Curt Discovery Time Delay 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



Video of Curt Discovery Trailer Brake Controller - 1 to 4 Axles - Time Delayed


Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Curt Brake Controller - Time Delayed Controller - C51120 Review

Today we're going to take a look at the Curt Discovery Trailer Brake Controller number C51120. This time delayed brake controller activates trailer brakes with a preset intensity. The signal is sent to the trailer brakes when the tow vehicle's brakes are activated.It has an adjustable thumb wheel power output that allows you to determine the amount of breaking force you would set to the maximum when you travel through a more hilly terrain with a fully loaded trailer and you would back off the power output when you're towing a smaller more lightweight trailer.It also features a sink switch here on the side. It allows you to adjust the aggressiveness of the brakes. If you want it full power in this position right here. It will increase the activation speed of the brakes and you would move it back in the opposite direction to achieve a smoother braking by supplying the power more gradually.

It has an easy to read digital display that communicates brake force output, sink setting and air codes and we'll attach this to a power supply in just a moment so you can see that a little better. Self-diagnostics function monitors the trailer connection and checks for shorts. It has a built in slide bar emergency manual override and again we'll discuss that more in just a moment. It has also has a quick and easy installation. It comes with the mounting bracket right here.

The screws to attach the bracket to the controller as well as a quick reference card if you have any questions. One of the differences between the time delay brake controller and a proportional brake controller is there's no need to mount this one level the way you would a proportional controller.You can mount it up, down, side to side, as long as you can see the digital display you're good to go. This application is for trailers up to four axles or eight brake assemblies. It's designed for use with electric brakes only and it does have a limited lifetime warranty. Now we're going to attach it to our power supply and the wiring harness that we're using here is the Curt Universal Wiring Adapter for Curt Trailer Brake Controllers, number C51515.

This particular harness ends in a pigtail and it is intended for vehicles who do not come with a factory installed brake controller port. Now when you hit the brake you will be able to see the digital display and say right here we'll use our output knob here. You can go from zero to ten and we'll set that at five for right now and over here our sink all the way to nine and then slide it back to zero. We will put that at five as well. When we talk about our emergency manual override say youre in traffic and somebody cuts you off and you have to hit the brakes really quick what you would do is hitch your emergency manual override and instead of the normal amount of time it would take for the trailer brakes to brake this removes the time delay function and the maximum output that you had preset it goes to the brakes immediately to help slow you down to prevent any accidents.

That should just about do it for our Curt Discovery Trailer Brake Controller number C51120.



Customer Reviews

Curt Discovery Trailer Brake Controller - 1 to 4 Axles - Time Delayed - C51120

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

Average Customer Rating:  4.8 out of 5 stars   (234 Customer Reviews)

Electronic controller activates electric trailer brakes with a preset intensity when you apply the brakes in your vehicle. Power output and braking aggressiveness are easily adjustable. Includes easy-to-read digital display and manual override. 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.

- C51120
by: Steven04/23/2019

Had the controler installed in just a few minutes. 634445



- C51120
by: Bob02/19/2019

Product worked as advertised. 2012 F150 already has the terminal. All adjustments work as they should with the trailer brakes. 606348



- C51120
by: Erik03/27/2019

This is by far the most pleasant buying experience I’ve ever had online. A wealth of information is provided for installation coupled with prompt delivery makes shopping for anything RV related a no brainer for me. etrailer is wonderful and have already started recommending this website to anyone I know. 614611



- C51120
by: Keith a11/19/2018

When i needed to replace my electric brake controller on my truck for pulling my trailers I first ordered from another dealer and when i got the unit and read the instructions there were about 3 items that i wasn't told about and sent it back ,so i kept searching for the controllers and came across e trailers , there were so many questions i had from my researching that when i called e trailers and talked with Preston he was so helpful in explaining the differances with controllers and i explained what i wanted and why he helped set me up with the right one .I then ordered the unit it was received faster than i expectided , it took me about 20 minutes to install the wiring harness and controller, I'm very happy with the customer service rep. Preston with help and time to explain and the choice i made thanks Preston and E trailers 584058



- C51120
by: Ty F.01/18/2018

Less than 1 yr after installing on a 2017 F250, controller quit working right. It would surge brake to some high number like 7 (10 being max) regardless of the controller setting which would lock up trailer brakes. Next time it would only allow a setting of 2.5 or 7.5... nothing else. Next time it would do something different. Called Curt who recommended unplugging it for awhile. Worked for awhile then started acting up again. They're going to send me a replacement. Tbd if replacement will be better. 468124



- C51120
by: Dale07/21/2018

Purchased this controller for limited use. Really like the vehicle specific plug adaptor that came with it. Makes for a quick clean install. Clean compact design and easy to use. 544267



- C51120
by: J.C. from Bay City02/24/2014

Ordered a brake control and an inline circuit breaker on Feb 11th and shipped the same day. I chose the least expensive shipping option (my bad). A combination of UPS/US Post Office, or so I was told after calling to find out where my shipment was. Tracking info said delivery by the 15th. When it didn't show I called etrailer and was told the post office had it and it was out for delivery...2 days later I finally received it (Feb 20th). I ordered a hitch a couple of weeks prior and received it in 2 days. A 49lb hitch vs a 1lb (maybe) package. Not etrailers fault but I can see why the post office is going broke with service like that! 117375



- C51120
by: George D10/17/2015

the brake controller with all the wiring plus the 7 pin plug was better than i thought . it even has great instructions and easy to read. the price was good . the 7 pin plug even has the 4 pin connector mounted in with it very glad that i bought it is everything that you need to make it work . everything about it is excellent very glad that i found it here at a good price . even fast shipping . again thanks for good product 230172


Comments

Use it for pulling camper works great even a good price fast shipping . Its been a year and still working great.

George D - 10/16/2016

21545

- C51120
by: Bob R02/05/2016

I bought a new car dolly with electric brakes to pull with our motorhome ( Fleetwood FlAIR 2001 ) as all states require brakes on trailers at all different weight levels. I called E trailer and spoke with Danna and after talking with her about different models I choose the C51120 time delay control, as it can be adjusted to work well with the tow vehicle . I received the control with in 3 days of the order and went to put it in and found under the dash wire a harness by Fleetwood which told where each wire on the controller went on the harness. I was able to hook it up sitting in the drivers seat. Completed the hook up and started to test the operation, to find I was not getting the proper readings. I talked with Tom and he said he would bench test a like control and report back to me, at 6 pm he left a message on our phone that he believed the problem was along the blue wire to the trailer on the tow vehicle . I started at the back of the, motorhome and moved forward testing for a brake signal, I found that the butt connector had pulled apart and was not getting current to the plug in at rear of coach. Hooked it back together and re taped the wires and it works like a charm. I want to thank all off you for the prompt and knowledgeable service, I would recommend E trailer to anyone who wants to deal with a great staff and company Thank you 237064


Comments

I used this controller to pull ma car dolly to AZ and back through all the mountains and it worked GREAT I am very happy with how it worked Great product

Bob R - 02/04/2017

22382

- C51120
by: Chris04/28/2018

Not too thrilled with this one. Three main issues listed in increasing order of magnitude. 1. One of the segments on the display died shortly after installing. 2. The adjustment wheel is very crude and hard to dial in. 3. This one is the killer, if you start by manually applying the brakes using the slider, and then put your foot on the brake pedal, and then release the lever, the BRAKES GO FULL LOCK! That's a design flaw in the circuit. 501648



- C51120
by: Justin08/02/2016

After reading the reviews of this product I decided to give it a try myself, with a great price. When I received it within a week along with the plug and play 7 prong trailer hitch adapter, I realized I was missing something. The plug and play adapter for this product. It showed me it when I was buying and for what ever reason I didn't have the option to add it as well. It was very easy to install, like I said plug and play. The problem is it does not work. followed all the directions, double checked everything I just don't have a signal to the trailer from the break controller. Good luck 278660



- C51120
by: Paul07/05/2018

This Curt Discover controller works great. Super easy to install if you get the pigtail for your model truck. I especially like the fact that you can install the bracket under the dash on my new 2018 Silverado using factory screw under the dash. No drilling required. As always wonderful pricing and delivery from E-Trailer. 533806




- 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

- C51120
by: Cynthia07/14/2018

The controller was easy to install. It works exactly as it should at a very good price. Costumer service is excellent. The first controller we received was broken. A quick phone call and two days later a new controller. Would definitely order from this company again. 541795



- C51120
by: B.R.K06/07/2019

Wish it had longer cabling, otherwise; So far so good! 654833



- C51120
by: Alan05/30/2019

Very detailed website information made ordering easy. Product delivered as promised and would use etrailer for future needs. 649189



- C51120
by: Jimmy05/28/2019

Easy to install and setup. 647591



- C51120
by: Pete L.04/26/2019

The wiring kit fits perfectly. I had a small problem with the operation of the brakes on my trailer but a quick call to the great service department and my problem was quickly rectified. I will do business again. 635248



- C51120
by: Ray04/19/2019

Work great easy to install would buy ag ain 633253



- C51120
by: Jeffrey04/04/2019

amazing fast shipping, thank you 617101



- C51120
by: Howard03/29/2019

Great product, works as expected, very easy install, shipping right on time, no damage at all to the product. Very happy with my purchase thanks etrailer for filling my needs. 615033



- C51436
by: Joshua03/02/2019

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



- C51436
by: Bob02/19/2019

Direct plug in with the truck. 606349



- C51120
by: Michael02/16/2019

Shipped and arrived in a timely manner. 605620



- C51120
by: Humphrey,02/15/2019

Easy install 605451



- C51120
by: Harry M.01/28/2019

I'm Very pleased with the quickness of receiving the brake controller for my 2019 Tundra and can't beat the price for a quality controller and adaptor wiring kit ! 600829



- C51120
by: Rick01/15/2019

Everything received promptly and as expected. Thank you! 597767



- C51120
by: Steve01/01/2019

terrific product,excellent fit,seamless transaction! 594246



- C51436
by: Todd12/03/2018

Plug and play, works as expected. 588143



- C51120
by: Todd12/03/2018

This is my second one. It just works and is priced right. 588142



- C51120
by: Steve10/30/2018

Good product selection and high quality. Good service and follow up. Quick and secure shipping. 578797



- C51120
by: Don10/17/2018

Excellent customer service very professional. Fast and easy shipping. Very knowledgeable staff. I will be back. 575040



- C51436
by: Cristofer09/30/2018
2017 Ford F-250 Super Duty

Exactly what I needed. Really easy to c onnect. 570272



- C51120
by: Kenneth08/06/2018

Worked very well 550732



- C51120
by: Joe07/22/2018

Product works great just as described . Did have a little trouble installing it but otherwise no issues. 544469



- C51120
by: George07/14/2018

Product is what fits my truck for proper operation. Compact and easy to use. Price is right and is easy to install. 541792



- C51120
by: Jon06/21/2018

Exactly what I wanted 524866



- C51120
by: Matt06/18/2018

Works very well! Nice product and easy install! Very satisfied! 523370



- C51120
by: Debra06/05/2018

Bought this for my father for father’s day gift. Worked great. He was glad to get it. 517633


Comments

He still loves it. Thanks

Debra - 06/05/2019

56197

- C51120
by: Luke06/04/2018

Installed in about 5 min. Arrived ahead of schedule and instruction videos were great. Will buy All trailer stuff here in future. 517464



- C51120
by: Tim L.06/04/2018

Good quality product ( electric trailer brake control) and fast delivery!! Very satisfied. Do recommend!! 517385



- C51120
by: Jeremy05/30/2018

Easy to install and does what I need it to. 514072



- C51120
by: Thanh05/30/2018

The break controller and dual plug in adaptor worked great for my 2014 QX60. Easy to install and worked perfect. 513770



- C51120
by: Curt02/16/2018

Easy installation. .watched there video made it easy to locate my trucks wires 476511



- C51120
by: Fred02/14/2018

Great glad to have bought it from e tra iler 475746



- C51120
by: Ron H02/14/2018

very Satisfied Customer. excellent Customer Service 475714



- C51436
by: Jon02/12/2018

Worked as advertised 475055



- C51436
by: Jim S.01/15/2018
2016 Ford F-150

This pigtail that Dan T. with e-trailer help me get order an shipped worked perfectly. It was a custom fit for 2016 F-150 w/ no tow pkg and a Curt 51120 brake controller. This will almost complete my conversion of my truck that had no tow pkg. In the end it will help my daughter tow her Shooting S barrel horse safely to the shows. Thank you Dan T. 467325



- C51120
by: Bernard01/06/2018

Arrived very quickly & in excellent con dition. 465209


Show More Reviews
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Ask the Experts about this Brake Controller
Do you have a question about this Brake Controller?


  • Brake Controller Install in 2014 GMC Sierra
  • The install procedure will depend on if you have a 1500 or a 2500/3500 Series. If your Sierra is a 1500 model, you will need a brake controller wiring adapter harness, part # C51451. The 2500 and 3500 series would have the tow package wiring that sits above where the driver's left knee sits. If you click the video link I've provided, you can see a controller being installed in a 2014 GMC Sierra 1500. The FAQ link I provided shows how to install a controller in the 2500/3500 model. The
    view full answer...

  • How to Install Curt Discovery Brake Controller in 2008 Ford F-150 with 7-Way
  • The Curt Discovery brake controller part # C51120 that you referenced can easily fit your 2008 Ford F-150 with the custom install harness part # C51322. This plugs into the brake controller install port under the dash of your truck and then into the back of the controller and you're set.
    view full answer...

  • OL Message on Curt Discovery Trailer Brake Controller
  • There could be a few different things happening with your Curt Discovery Trailer Brake Controller part # C51120. The first thing that could be happening is that you have a short on the red stop light switch wire. In order to rule this out you will need to probe the red wire going into the back of the brake controller. There should only be power on this wire with the brake pedal depressed. If there is when it is not then you know there is either a short in this wire or the stop light switch
    view full answer...

  • Adding a 7-Way Trailer Connector and Brake Controller to a 2004 Nissan Xterra
  • I will be happy to clear up what all you will need to add the equipment to tow the trailer and activate the electric brakes. First, if your 2004 Nissan Xterra does not already have a trailer hitch you will need to add one. A popular option is Curt trailer hitch # 13183. This is a Class III hitch with a 2 inch receiver. The hitch itself is rated for 400 pounds tongue weight and 4,000 pounds gross trailer weight but limited to the vehicle capacity if lower. I also recommend etrailer
    view full answer...

  • How to Find Out Where Cold Side of Stop Light Switch Is
  • In order to find the stop light switch in your truck you will need to use a circuit tester such as # 40376. Find the wires at the top of your brake pedal and use that circuit tester to find the wire carrying a signal only when your truck's brake pedal is engaged.
    view full answer...

  • Which is Better a Time Delayed or Proportional Brake Controller
  • Between the two controller I would go with the proportional Curt Triflex part # C51140 over the time delayed Curt Discovery part # C51120. A time delay controller is so named because there is a delay between the time that you initially apply the brakes in your tow vehicle and the time that the controller reaches maximum power output. Unlike a proportional brake controller, which activates your trailer's brakes based on the deceleration of your tow vehicle, a time-delayed controller sends
    view full answer...

  • Brake Controller Installation Harness Recommendation for a 2015 Chevy Suburban
  • Yes, there is a port under the dash of your 2015 Chevy Suburban that will allow for a painless installation of a brake controller that won't require splicing. The harness to go along with the Curt Brake Controller part # C51120 that you referenced is the part # C51452. If you went with our most popular brake controller, the P2 part # 90885 you would only need the harness part # 3016. See the install video I attached.
    view full answer...

  • Brake Controller Wiring Adapter for a 2015 Toyota Tacoma with Factory 7-Way
  • No worries, the 5-wire harness will work just fine because the extra connection is for the illumination circuit and it's not needed. The Curt Discovery trailer brake controller # C51120 is a fit for your 2015 Toyota Tacoma and the direct fit pig tail adapter # C51362 you referenced is correct. You will simply plug the adapter # C51362 into your factory brake controller tow port and route the pigtail to the location of your choice so you can connect your brake controller # C51120.
    view full answer...

  • Curt Discovery Brake Controller Displays Decimal Point When Not Connected To Trailer
  • The Curt Discovery Trailer Brake Controller - 1 to 4 Axles - Time Delayed, # C51120, is working properly. It is designed to display the decimal when no trailer is connected and number when connected. The numbers should increase as you activate your manual override when connected to the trailer as well. I have attached the installation details for you and a video to help.
    view full answer...

  • How to Find and Access the Brake Light Switch Wire on a 2015 Toyota Highlander for Brake Controller
  • If you check out the video I attached you will see how we installed a brake controller in a very similar 2014 Toyota Highlander as your 2015 model. We had to remove the lower dash panel (13:00 mark of the video), to make accessing the green wire possible. The kit used for the install in the video is the part # ETBC7.
    view full answer...

  • Brake Controller Installation on 2011 Toyota Tundra
  • If your 2011 Tundra has the factory tow package, which includes the factory installed 7-way trailer connector on the rear bumper, it will be equipped with the tow package plug under the dash, as shown in the photo I've edited for you. Some models with the factory 4-pole (or 4-pin) trailer connector will also have the plug under the dash, you'll need to look for a white plug located above and to the left of the emergency brake pedal, above the toe kick. Occasionally, the plug will be located
    view full answer...

  • Testing Curt Discovery Trailer Brake Controller With No Display
  • It is possible your Curt Discovery Trailer Brake Controller # C51120 is faulty, but first, just double check all your connections and specifically ensure the black and white wires are not reversed. Also take another look at your circuit breaker to make sure it is not blown, but if everything but the display is working, that would indicate a problem with the unit.
    view full answer...

  • Wiring Curt Brake Controller # C51120 in 2002 GMC Sierra 1500
  • Based on your description of the problem with your Curt Discovery # C51120 Time Delayed Brake Controller one cause could be a mis-wired plug-and-play harness. Please refer to the photo provided which shows how the vehicle side of the harness should be wired. For reference I have also linked a help article concerning brake controller installations in GMC trucks. The connector should be pinned out with the four wires as shown in the provided photo. If the red wire is connected to a different
    view full answer...

  • Installing Curt Discovery Brake Controller # C51120 on 1988 Ford F150
  • To hardwire the # C51120 Curt Brake Controller, you can either cut off the existing plug on its wiring harness or use the universal pigtail, part # C51515. The universal pigtail would provide an easy way to quickly disconnect the brake controller, should it become necessary. You would then use our Brake Controller Installation Kit, part # ETBC7. If you do not already have a functional 4-pole trailer connector you would also need to install one using part # 118316. The install kit includes
    view full answer...

  • Installing A Brake Controller in a 2008 GMC Yukon XL Without Plug and Play Adapter Harness
  • On your 2008 GMC Yukon XL, there is not a direct plug and play harness for a brake controller. This is because no plug is present under the dash, however the needed wires are already run so it is a simple install. You will connect the brake controller wiring with the vehicle wiring already present under the dash with butt connectors like # 05731-5. The Curt Discovery Timed Delay Brake Controller # C51120 gives you the option to either cut the connector off the brake controller or
    view full answer...

  • Curt Discovery Brake Controller Display Flashes with Left Turn Signal
  • It could be a wiring issue. Specifically it is likely related to the brake controller red wire. If that wire is not attached to the correct circuit it can cause some strange things to happen. The red wire needs to be connected to a brake switch wire that only has power when the brake pedal is pressed. If that same wire has power then the headlights or a turn signal are on then it is not the correct wire. I have heard that the correct brake switch wire is the white wire so use a circuit
    view full answer...

  • Adapter Needed to Install the Curt Discovery # C51120 on a 2005 Ford F-150
  • To install the Curt Discovery Trailer Brake Controller # C51120 on your 2005 Ford F-150 you will need the Curt Custom Wiring Adapter # C51322. This connector will be found under the dash on your driver side. I have attached a video of this adapter being used to install the Curt Venturer # C51110 on a 2004 F-250 that you can use as a reference.
    view full answer...

  • Troubleshooting Trailer Brakes that Lock Up When Trailer Is Connected
  • There is a short or a mis-wire on the 7-way you installed. It sounds like the 12 volt accessory circuit is shorting out to the brake output circuit which is causing the brakes of the trailer to lock up anytime the 7-way is connected. This is a fairly common issue as wiring up connectors is a bit confusing. Since the controller never senses a connection it sounds like the problem is the circuits just being wired backwards. I attached a chart that has what the 7-way pin out should look like.
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  • Parts Needed to Install Curt Discovery Brake Controller in 2014 Chevy Tahoe
  • To install the Curt Discovery brake controller # C51120 in your 2014 Chevy Tahoe you'll need the install harness part # C51515. This wires to the blunt cut wires that are under the dash of your Tahoe. To see how it installs check out the install video that shows this controller installed in a similar 2015 Chevy Tahoe.
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  • 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.
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  • 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.
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Info for these parts were:

Edited by:
Leah B
Expert Research:
Jackie C
Expert Research:
Michael L
Written by:
Lindsey S
Expert Research:
Michael H
Expert Research:
Jameson C
Video Edited:
Joshua S
Test Fit:
Nicholas E
Expert Research:
John H
Updated by:
Adele M
Video Edited:
Andrew L
Expert Research:
Adam R
Video Edited:
Dustin K
Photos by:
Jim W
Test Fit:
Shane T
Expert Research:
Jeffrey L
Test Fit:
Randy B
Updated by:
Kristina F

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Ford F-150 Accessories