Curt Discovery Trailer Brake Controller - 1 to 4 Axles - Time Delayed
Universal Wiring Adapter for Curt Trailer Brake Controllers

Part Numbers: C51120,C51515

Retail:$107.00
Our Price: $88.63
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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

Item # C51120

California residents: click here

Product Expert Kathleen M

Is this right for you? Product Expert Kathleen M says:

Yes, if you:

  • Have a hard time finding a spot to mount a controller in line with the direction of travel
  • Only need a basic controller that gets the job done and doesn’t break the bank

No, if you:

  • Have issues with your trailer brakes locking up
  • Haul a trailer with hydraulic brakes


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

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

Features:

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


Installation of Curt Brake Controller Adapter

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


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


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



51515 Curt Universal Quick Plug Brake Control Adaptor Harness with Pigtail

California residents: click here





Customer Reviews

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

Universal Wiring Adapter for Curt Trailer Brake Controllers - C51515

Average Customer Rating:  4.8 out of 5 stars   (554 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. This wiring adapter is designed for vehicles that do not come equipped with a factory brake control wiring harness port. One end plugs into your Curt trailer brake controller while the other end splices into your vehicle's wiring.

- C51120
by: David03/30/2021

I finally got a chance to hook up to a trailer. Everything works fine. I figured it would. I had bought a Curt controller years ago (2006?) And pulled many heavy trails with no worries. I was dismayed by the packing. There was so little bubble wrap in the box that the controller bounced around so much in its clear plastic that contents of that clear box were spilled out into the shipping box. Room for improvement there.



- C51515
by: Peter06/22/2021

This is a "must have" if your vehicle did not come with a "tow package". If your vehicle does have a tow package try to get the correct wiring adapter and you can just plug it in without having to make wiring connections.



- C51120
by: Bob C06/22/2020

We purchased this for our 18 ft camper It is very good working brake system. We did have a wire fray but no fault of the system. We called the help line and they helped us diagnose it . Customer service is very good****


Comments
Like it w
Bob w - 06/23/2021


- C51120
by: Peter06/22/2021

I purchased this controller to install in my daughter's 2013 Ford Explorer. It is the exact same model as the one I have in my 2010 Ford F150. The "slide" adjustment on this one does not have as much resistance to adjustment as my original so setting it is requires a very delicate touch. I would probably would have asked for a replacement but I did not have time to make an exchange as she needed to use it right away. However, it appears to be operating fine and did not move from it's position once it was set. I would have rated it as excellent except for this one weakness.



- C51515
by: David03/30/2021

Worked like it should. You might leave the sleeve uninstalled on the 4 wires for the installer to fit. I only needed it for the 2 wires going through the firewall. It was not useful for the ground and switch wire.



- 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.



- C51120
by: Mark07/21/2021

It’s been almost a year and never a problem. Set it and forget it until you change trailer loads.



- C51515
by: Andy02/05/2021

Spoke with etrailer on the phone, they helped me get the right hitch for my car. The hitch was good quality, and their install video really helped. They shipped promptly and everything arrived in just a few days. Great experience.



- C51515
by: Frank S02/14/2014

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



- C51515
by: John06/22/2021

Easy to install, just have to verify wiring colors (different than wiring harness colors on vehicle that could be confusing to some.)



- C51120
by: William06/01/2021

It connected to our motorhome easily. Have not connected the trailer to the motorhome yet to see if it functions properly



- C51515
by: Ben06/06/2021

Great product. After reading instruction and watching a video or two, install on my 2011 Yukon was done in less than an hour and it works great.



- 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.


Comments
No issue yet to date. Controller worked perfectly during last year’s RV season!
Erik - 04/01/2020



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

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


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



- 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


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



- C51515
by: Tom C.03/10/2014

I have the Dodge Ram Truck 94 model with factory wire 7 connector plug. This is the truck that many people can't find the blue wire under the dash. 94 model didn't come with a factory wire plug under the dash like later models have. I found the wire tape to the main wiring harness about two inches from the fire wall to the right of the emergency brake paddle. This harness worked great



- C51515
by: BiscuitsNGravy10/21/2013

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


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


- 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


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



- C51120
by: Jerome03/30/2021

THe installation was pretty simple and the controller has worked flawlessly, once I set it.



- C51515
by: Ted07/03/2014

I purchased the wiring harness to aid with hooking up the Curt Brake Controller I had previously purchased. The shipment was fast. The product was perfect. The on-line installation video was perfect and allowed me to complete the installation like a professional. I have never purchased anything from etrailer.com .... but should I ever need anything in the future, they will be my first choice.


Comments
Perfectly. No issues at all with wiring or controller.
Ted - 07/03/2015



- C51120
by: Tacoma Stan09/11/2016

Fit nicely under the dash on the left side. Also installed a 7/4 pin connector in the bumper, replacing the blank plug from the factory(etrailer p/n HM40975-11998)



- C51120
by: Mike09/11/2019

Works as advertised. Only minor issue is mounting the unit in a 09 Colorado.


Comments
Still works very well.
Mike - 09/12/2020


- C51515
by: Forrest07/13/2021

Still works great!



- C51515
by: Wiley09/17/2020

Every item I have ever gotten from etrailer has always exceeded expectations. The how-to videos make installation possible. etrailer is always my first shopping stop. Thanks.



- C51515
by: David P04/02/2020

etrailer products and service are excellent! With their helpful videos and staff (plus a little help from Curt Manufacturing and our teardrop trailer manufacturer (CampInn)) I was able to install electric brakes on the trailer, and a controller in my vehicle by myself. I had never installed electric brakes before. Everything works perfectly!


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


  • Brake Stoplamp Switch Wire Color For Brake Controller Install on 2016 Ford F150
  • You'll be looking for a purple and white wire, but if you're wanting to install a brake controller there is a plug and play option that would require no cutting or splicing. If you look at the installation video I've linked for you, you can see that the brake controller connector is located behind the dash, all you'll need is the correct wiring harness to connect the controller and the vehicle and you'll be good to go. If you're using a Curt brake controller like the # C51120, you would
    view full answer...

  • Curt Brake Controller Adapter Harness for a 2020 Jeep Grand Cherokee
  • In order to install the Curt Discovery Trailer Brake Controller part # C51120 on a 2020 Jeep Grand Cherokee you will need the Curt Custom Wiring Adapter for Trailer Brake Controllers part # C51446 which makes for a plug and play installation. I have attached an install video for you on a similar model year which should be the same if not similar in regards to the plug location. The brake controller harness for a Jeep Grand Cherokee has not changed since 2011.
    view full answer...

  • How To Install Curt Discovery C51120 In 2017 Chevrolet Equinox W/ ETBC7
  • I would be happy to help! I looked up your order and it looks like you purchased the following products: 7-way Connector # ETBC7 4-way Connector # C56210 Curt Discovery Trailer Brake Controller # C51120 Curt Wiring Adapter # C51515 Now it looks like your 2017 Chevrolet Equinox does not have the factory trailer connector. If that is the case then the # C56210 you ordered will not work as it is designed for vehicles with the factory trailer connector. You would need the # C56594
    view full answer...

  • Curt Discovery Brake Controller Not Showing Trailer Connected on 2003 GMC Sierra
  • Thank you for your purchase from etrailer of the Curt Discovery Trailer Brake Controller # C51120. The culprit on your 2003 GMC Sierra likely isn't any type of fuse, but there are other potential issues when this happens, most likely with the issue being a short on the blue brake wire, a corroded connector on the truck or trailer side, or an issue with the brake magnets. I would start by checking the blue brake wire, particularly on the trailer, to see if it is pinched, damaged, or otherwise
    view full answer...

  • Tapping Into Brake Light Circuit to Install Brake Controller In a 2011 Chevy Equinox
  • On a 2011 Chevy Equinox you cannot tap into the brake light switch to install a brake controller. You have to get the signal from the BCM (body control module). It is located up under the dash to the left of the brake pedal. There is a 26-pin connector. You need the wire in position 11. It should be a white wire. I have included a picture that should help. I have also included a link to another answer page to the right that also has that picture.
    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...

  • Installing a Brake Controller in a 2009 Chevy Suburban
  • The 2009 Chevy Suburban does not have a port to plug in a brake controller which is the same as the trucks of the same year. But it does have the tow package wire bundle up under the dash, to the left of the steering column, held together with a white tag. Pull the wire bundle out to wire in a brake controller. With Curt brake controller # C51120 you will also need pigtail # C51515. Then you can make the following connections: Vehicle red/black wire to controller black wire for 12
    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...

  • 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 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...

  • Curt Discovery Brake Controller Only Works With Manual Override and Not When Pressing Brakes
  • This sounds like an issue on the red wire that supplies power when your brakes are depressed. When you use the manual override, it bypasses the need for a brake signal on the vehicle and applies power to the trailer brakes; that is why it is lighting up when you engage the manual override. You'll need to check the red wire that runs from the brake controller for any type of loose connection, broken wires, etc.; this wire should attach to the stop light switch above the brake pedal that
    view full answer...

  • Curt Discovery Brake Controller Is Only Showing A Dot When Engaging Manual Override
  • The Curt Discovery Trailer Brake Controller, # C51120, should show only the decimal point dot when the controller is activated and a trailer is not connected. If it shows the dot all the time, the red wire is connected to the wrong side of the stop light switch or the wrong switch completely like the cruise control. If you have only the decimal point when the trailer is connected, the usual cause is that the brake controller does not sense the trailer brakes. This could be due to corrosion
    view full answer...

  • Which Brake Pedal Stoplight Switch Does Red Brake Controller Wire Connect to on 2013 Ford Escape
  • The second generation Escape (2008-2012) used a purple and white wire for the stoplight switch, but I could find no information about your 3rd generation Escape. The best way to find the correct wire is to use a circuit tester like part # 40376 and test each of the wires. The wire that only goes hot when the brake pedal is pressed (not with the headlights or turn signals) is the wire you want to tap that red brake controller wire into.
    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.
    view full answer...

  • How to Access Vehicle Brake Light Signal for Trailer Brake Controller Installation
  • If your 2005 Toyota Sequoia has a factory-installed 7-way trailer connector you can install the Curt Discovery trailer brake controller # C51120 using only the mating wiring adapter part # C51362. If it does not then the installation will be hardwired. You can gain access to the vehicle brake light signal, which is what triggers the Discovery controller to generate output voltage for the trailer brakes, either by tapping into brake light wiring or by installing a fuse tap in the brake
    view full answer...

  • Troubleshooting Curt Discovery Brake Controller Issues on Ram 1500
  • The Curt Discovery Brake Controller # C51120 is a time-delay type that is intended to send out a pre-determined amount of braking power after you have applied the vehicle brakes. The other type that is often preferred is the proportional type that will actually sense the amount of braking force in the tow vehicle and send a proportional amount of braking power to the trailer, without a time delay. Based on the symptoms you described I think the issue could be with the wiring on the trailer.
    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...

  • Parts Needed to Install the Curt Discovery Brake Controller # C51120 on a 2013 Dodge Durango
  • The Curt Discovery Trailer Brake Controller, # C51120, and the Custom Wiring Adapter, # C51446, will work on your 2013 Dodge Durango without splicing as long as your Durango came with a factory 7-way trailer connector at the trailer hitch. The 7-way trailer connector would indicate that your truck has the factory tow package, which would include a brake controller plug under the drivers side dash. You should see a gray connector just to the left of the steering column. If your Durango
    view full answer...

  • Wiring Adapter for Installing Curt # C51120 Discovery Brake Controller on 2014 Ford Explorer
  • To install the Curt Discovery # C51120 brake controller on your 2014 Explorer, you'll need the Curt wiring adapter, part # C51322. The plug for the brake controller is located under the dash, behind the handle for the hood release.
    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...

  • Troubleshooting Curt Brake Controller Installation in 2007 GMC Sierra New Body Style
  • First I suggest making sure you are testing the brake circuit pin on your Sierra's 7-way trailer socket. If you refer to the linked photo of a trailer connector you will note the brake controller's output is carried on the pin at the 5:00 position; the ground is at the 7:00 position. If you happened to test the 12V auxiliary power circuit, carried on the pin at the 2:00 position, it will have power at all times. I see that you purchased Curt Universal Wiring Adapter # C51515 which
    view full answer...

  • Adapter for Curt Venture Brake Controller on VW Touareg
  • In order to use the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515 with your Curt Venturer # C51110 brake controller, you will need additional parts from your Volkswagen dealer. Please see the attached help article on installing a brake controller in 2005 and up Volkswagen Touareg's. It states in part: "To install a brake control on a 2005-current Volkswagen Touareg or Porsche Cayenne using the factory brake control connector, you will need to assemble a brake
    view full answer...

  • White Ground Wire Is Taped To Orange Wire 2009 GMC Sierra 1500 Brake Controller Install
  • You want to use the white wire in your photo for the ground. The other orange wire is the CHMSL circuit which stands for center high mount stop light wire. It is not used by a brake controller so you can tape it up and stow it out of the way. You will need 4 wires to install the brake controller, 12 volt power (red and black in your photo), trailer brake output (solid blue in your photo), stoplight circuit (light blue with stripe in your photo) and ground (white).
    view full answer...

  • Brake Controller Recommendation for a 2012 Mercedes GL450
  • In order to install a trailer brake controller on your 2012 Mercedes GL450 it will require hardwiring in the controller unless the Mercedes dealer has a wiring harness specific for a brake controller and your vehicle. If they do then you will need to wire in the controller to the Mercedes harness by function. On a brake controller, the wire functions are as follows: White is ground Black is 12 volt power Blue is output to the trailer brakes Red is input from the brake switch On
    view full answer...

  • Troubleshooting Curt Venturer Brake Controller Installed on 2011 Dodge Ram 1500 Pickup
  • Getting a single green LED on the display indicates that there's no trailer connected. Since you're getting this with the trailer connected, it would seem to indicate that the brake controller isn't 'reading' the trailer for some reason. The most common reason for this to happen would be a dirty, corroded or damaged connector on the vehicle or the trailer. Examine the trailer connectors, and ensure everything is clean. If you see any white or green corrosion on the pins or sockets of the
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  • When Does Brake Output Circuit of Vehicle 7-Way Have Voltage
  • The brake output circuit on a 7-way (5:00 pin) will only have as much voltage on it as the brake controller is sending. Typically this going to depend on the amount of gain selected on the controller and other factors like brake controller style and ramp up speed of the controller. The only time the circuit would have voltage without the brake pedal being applied would be if you had the manual override lever of the controller slid. I attached a couple help articles on brake controllers
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  • Installation of Curt Brake Controller on 2009 GMC Sierra 1500
  • When it comes to installing a brake controller like the Curt # C51170 using the adapter # C51515, the color of the wiring isn't always a reliable way to determine the functioning of a wire, so you'll likely want to test the functions using a circuit tester like the # PTW2993. In some cases the colors will match up, but it's not always the case. As long as you're able to match up the correct wires under the dash to the adapter, you'll be able to use the brake controller without issue. We
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  • 7-Way Installation Kit to Install Curt TriFlex Brake Controller in 2017 Audi Q5
  • So far so good but you need one more thing in order to install the Curt TriFlex Trailer Brake Controller # C51140 with Adapter # C51515 in your 2017 Audi Q5. Now that you have the 4-way # 119250KIT installed you will need to add the Universal Installation Kit for Trailer Brake Controller # ETBC7. This is going to give you the 7-way connector, circuit breakers and rest of the hardware needed to complete your brake controller installation. I have added links to a pair of help articles
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  • How to Install the Curt Wiring adapter # C51515 on a 2008 Chevrolet Silverado
  • To install the Curt Wiring adapter # C51515 in your 2008 Chevrolet Silverado you will need to hardwire it under the dash. To be sure that the wire bundle you found under the dash is the correct set of wires I would check the white tag for any indication as to what each wire is for. If none of them have labeling then it would be best to test their functions with a circuit tester like part # PTW2979. You will then connect the following wires from the Curt adapter to the following functions: Blue
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  • Removing Lower Panel of 2019 GMC Canyon to Install Curt Spectrum Brake Controller
  • Thank you so much for your purchase from etrailer of the Curt Spectrum Trailer Brake Controller # C51170. We appreciate that, and in order to remove the front panel, you literally just have to remove the screws and work the panel out to remove it. If you go to about the 10:10 mark of the video I linked below you can see how our installer did this. The video is on a Chevy Colorado but it will be the same for your truck.
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  • Brake Control Harness # 51515 Installation Process in 2008 and 2013 Chevrolet Silverados
  • The Curt Brake Controller Harness you referenced, part # C51515, can be used for both the 2008 and 2013 model years of the Chevrolet Silverado since it is a universal-fit harness. For your 2013 Silverado you will want to follow the procedure outlined in the linked article. Please refer to the photo provided which shows the vehicle tow package wiring that can be found under the dash. You will connect these wires to the leads on the Curt harness as per the article, using butt connectors
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  • Custom Wiring Adapter for 2012 Chevy Silverado Curt Brake Controller
  • If you are looking for the custom adapter for the Curt Reflex Trailer Brake Controller # C51130, you will need the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515. Unfortunately, no factory plug is present under the dash on your truck, but the needed wires are already run. You will connect the brake controller wiring with the vehicle wiring already present under the dash. It is a two foot long wire. These are twelve gauge wires with a protective coating to prevent
    view full answer...

  • Troubleshooting Brake Controller Not Allowing Truck To Start
  • For your 2014 Chevy Suburban, no plug is present under the dash, but the needed wires are already run. You will connect the brake controller wiring with the vehicle wiring already present under the dash using the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515. It seems the 2007 to 2013 brake controller wiring was carried over into 2014 for your vehicle. I've attached and article to assist. The issue you are experiencing is most likely because you have a plug
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  • Brake Controller and Install Harness Recommendation for a 2006 Jeep Commander
  • The correct Curt brake controller install harness you will need for your 2006 Jeep Commander is the part # C51515 that you referenced. I would recommend you go with a proportional brake controller with it like the Curt Triflex part # C51140 as it will sense the amount of braking you are applying with your vehicle and will provide a proportional amount of braking power to the trailer. Some models will require a wiring kit to run wire to the battery. This may require drilling a hole
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  • Wiring Adapter for Curt Electric Brake Controller on 2016 Toyota Tacoma
  • We do offer the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515. This adapter will connect with the plug on the back of the Curt electric brake controller on one end and the other end will allow you to hardwire install the brake controller. If you need to add a 7-Way to your tow vehicle, the # C51515 adapter will work well with the Universal Installation Kit for Electric Trailer Brake Controller # ETBC7. The instructions for this hardwire installation are linked
    view full answer...

Info for these parts were:

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

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