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  1. Trailer Brake Controller
  2. CURT
  3. Electric
  4. Electric over Hydraulic
  5. Proportional Controller
  6. Dash-Mounted Knob
Curt Spectrum Trailer Brake Controller - 1 to 4 Axles - Proportional - Dash Mount

Curt Spectrum Trailer Brake Controller - 1 to 4 Axles - Proportional - Dash Mount

Item # C51170
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Our Price: $225.95
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Trailer Brake Controller
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Product Expert Kathleen M

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

Yes, if you:

  • Want a seamless factory look without having to drill into your dash
  • Like getting at-a-glance feedback about braking status and trailer connection
  • Have a hard time seeing indicators that are dimly lit, especially when towing during the day

No, if you:

  • Rely on the manual override to feather the brakes if someone cuts you off or to reduce sway
  • Swap trailers often - getting this controller adjusted takes a little finesse
Proportional brake controller installs anywhere in your cab and at any orientation. User-friendly, dash-mounted control knob with 10 tri-color LEDs creates a clean, OEM look. Easily adjust braking output, switch between modes, and view diagnostics. Lowest Prices for the best trailer brake controller from CURT. Curt Spectrum Trailer Brake Controller - 1 to 4 Axles - Proportional - Dash Mount part number C51170 can be ordered online at or call 800-298-1624 for expert service.
  • All Info
  • Reviews (204)
  • Q & A (0)
  • Photos
  • Why etrailer?

CURT Trailer Brake Controller - C51170

  • Electric
  • Electric over Hydraulic
  • Proportional Controller
  • CURT
  • Dash-Mounted Knob
  • Up to 4 Axles
  • Automatic Leveling
  • Hidden
  • 360 Degrees
  • Indicator Lights

Proportional brake controller installs anywhere in your cab and at any orientation. User-friendly, dash-mounted control knob with 10 tri-color LEDs creates a clean, OEM look. Easily adjust braking output, switch between modes, and view diagnostics.


  • 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
  • Push-button rotary control knob mounts on your dash for easy access and a clean appearance
    • Allows for convenient braking output and sensitivity adjustment
    • Equipped with 10 tri-color LEDs to display settings and diagnostics
    • Provides easily accessible manual override - just press knob to activate
  • Main module mounts out of sight and at any orientation
    • No more banging your knee on a bulky controller
    • No interference with airbags or other vehicle accessories
  • Triple-axis accelerometer is highly responsive to ensure smooth, uniform stopping action
    • Allows unit to automatically level and calibrate
  • Manual override functions as time-based for a slow reduction in trailer braking
  • Compatible with ABS brakes, cruise control, low-voltage, and pulse width modulation (PWM) systems
  • Multiple mounting options - choose between drill-mount or adhesive-mount
    • Mounting hardware and adhesive pads included
  • Plug-in, vehicle-specific brake-control adapter (sold separately) can be used for certain applications to reduce installation time
  • Assembled in the USA


  • Application: trailers with up to 4 axles (8 brake assemblies)
    • Designed for use with electric or electric-over-hydraulic trailer brakes
    • Works with 12-volt vehicle electrical systems
  • Main module dimensions: 3" long x 3-1/2" wide x 7/8" tall
    • Horizontal distance between mounting holes (center to center): 3/4"
    • Vertical distance between mounting holes (center to center): 2-3/4"
  • Control knob diameter:
    • Base diameter: 1-3/4"
    • Knob diameter: 1"
  • Control knob overall height: 1-1/2"
  • Full length of wiring harnesses when connected: 48"
  • Limited lifetime warranty

Spectrum Dimensions

Whether you're a seasonal or weekend tower, you'll appreciate the out-of-the-way, easy-mount design and factory appearance of the Spectrum brake controller. The rotary knob allows for convenient adjustment, and it is lined with sleek, multi-color LEDs that provide valuable diagnostics.

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.

Once the Spectrum is mounted, it will sense - via an internal 3-axis accelerometer - how your tow vehicle brakes. This 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.

How to Use the Spectrum Brake Control

The Spectrum provides the smooth, precise braking action that you've come to expect from Curt brake controllers while allowing you to maintain the from-the-factory look of your vehicle. Make all of your braking adjustments from the dash-mounted rotary knob, which is equipped with 10 tri-color LEDs for simple monitoring. The LED lights change color to display different information about the controller, including which of the 4 operating modes is selected and multiple diagnostic indicator sequences.

Spectrum Control Knob

To switch between modes, press the control button in the center of the knob.

Spectrum Modes and Functions

Output: The output mode lets you adjust the maximum amount of power that will be applied to your trailer's brakes. You will need to adjust the output during the initial setup, but following that, you should only need to adjust the output control when the trailer load changes, if you switch trailers, or when road conditions change. Optimum output should cause your trailer brakes to function effectively without locking up.

Sensitivity: In sensitivity mode, you can fine-tune the power by adjusting the sensitivity of the internal sensor to get either more or less aggressive braking.

Boost the setting to get 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.

You may need to adjust the sensitivity to accommodate for driver preference, trailer load changes, or changing road conditions.

Manual Control: Press and hold the button on the knob to activate the manual override.

Manual control mode is used to activate the trailer brakes independently of your tow vehicle. Doing this can have several advantages. Slowing the trailer down a bit as you travel can help to pull the trailer back in line behind your tow vehicle when you experience sway. You can also use the manual override to achieve a slow reduction in speed by creating just enough drag to slow your entire setup using only the trailer brakes. In addition, the manual override can help prevent a jackknife situation by limiting the momentum of your heavy trailer as you travel down steep hills.

When the manual control is pushed, the brake control will ramp up the trailer brakes until the maximum power output set is reached. If you realize that you need more power immediately, turn the control knob clockwise to reach maximum power faster.

The maximum power for the manual override can be chosen during installation via a small switch at the rear of the unit. The brake control unit is factory-set with the switch in the "ON" position, which allows 100% trailer braking power when manual control mode is actuated, regardless of the output control setting. When the switch is in the "OFF" position, the maximum override braking power will be determined by the output control setting.

The state of California requires that your trailer's brake lights illuminate when the manual override on your electric brake controller is activated. Therefore, to comply with state regulations, the Curt Spectrum offers a brake light activation feature. A small switch at the rear of the unit controls the unit's brake light activation feature, and it is factory-set in the "ON" position.

Simple, Out-of-the-Way Installation

Long gone are the days of knocking your knees on your brake controller. The 2-piece Spectrum can be installed nearly anywhere, and at any orientation.

Spectrum Control Knob LEDs Illuminated

First, determine your preferred location for the control knob. This is where you'll make braking adjustments, so it will need to be easily accessible while you're driving. Whether the knob is installed in a blank panel switch, on an open area of your center console, or somewhere on your dashboard, the simple, subtle design will provide a clean, uncluttered look. And the knob sits flush against any flat surface with no parts protruding behind the mounting location. This means that there is less chance of interference with wires and instrumentation behind your dash or console, so you have more mounting options than you might with other similar brake controllers.

Spectrum Control Unit Mounted Under Dash

Once you have determined where to mount the control knob, you'll need to find a good place to install the main unit. The only mounting restriction for the unit is that the included 4' long plug-in cable must be able to reach between the main unit and the knob.

The triple-axis motion-sensing accelerometer that is inside the main unit detects the inertia of your vehicle and trailer, and it uses this information to recognize the direction of travel and any change in position. Because this feature can read the direction of travel, the main unit can be mounted at any orientation for greater flexibility.

If your vehicle already has a plug-in brake controller wiring harness, just connect the main control module to it. Otherwise, you will need to purchase a vehicle-specific wiring harness (sold separately) to plug into. If a harness is unavailable for your vehicle, hardwiring will be necessary.

Both the control knob and main module can be mounted using the included hardware or adhesive pads for fast and easy installation.

For assistance in properly wiring the Curt Spectrum, please refer to the diagram below:

Spectrum Wiring Diagram

Installation Accessories

See'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.

Note: If a custom brake control wiring adapter is not available for your vehicle, a 30-amp circuit breaker (sold separately) may be required for installation.

51170 Curt Spectrum Trailer Brake Controller

Installation Details C51170 Installation instructions

California residents: click here

Customer Reviews

Curt Spectrum Trailer Brake Controller - 1 to 4 Axles - Proportional - Dash Mount - C51170

Average Customer Rating:  4.6 out of 5 stars   (204 Customer Reviews)

Proportional brake controller installs anywhere in your cab and at any orientation. User-friendly, dash-mounted control knob with 10 tri-color LEDs creates a clean, OEM look. Easily adjust braking output, switch between modes, and view diagnostics.

- C51170

Everything installed great. The overall look of the knob if excellent. The direct plug in to the Ford OEM brake plug is excellent. Have not towed anything yet. P.S.: The screw-in base with well nut - which is the more secure option (not the adhesive option) for the knob... the screw prevents the knob from seating perfectly square... the base bottoms out just slightly on the screw. It does click in, the screw is a very flat pan head... perhaps there is a flatter screw or the there is more space in the knob undercarriage, but another 1/16" of space probably gets it just right. If the seating gets weird (i.e in cold weather may shrink cause plastic to contract slightly and lose seating, I can always use a machine screw and nut washer to clean it up... plenty of space to access the fastener from mounting place. 2008 Ford Expedition.

- C51170

This controller is a really good concept but kind of challenging to get dialed in correctly for each load. When braking in a straight line it performs as expected but when braking while turning or on bumpy roads it often times surges the brakes making them lock up. I have been using this product for 1 year and am now figuring out ways to work around the surges. Best way I've found is to keep the sensitivity on high and only adjust the power setting. The 4 star rating on this product is for how small and sleek the adjustment knob is vs standard brake controllers installed In the dash it feels almost factory. Install took about 5 -10 minutes Overall I am happy with this purchace it's just not quite as user friendly as I'd hoped.

- C51170

I'm very happy to have the ability to have (Brakes) on my trailer now since Jeep dident offer A brake controller . I just wish it was A little easier to adjust & dial in . I have somehow misplaced the pocket instructions & cant get it to adjust any better now . It would be nice if you could just turn it up & get more braking out of it ?? Not real pleased with all the sequences needed to get it to do what should be A Simple job !!!!

Thank you for your review on the Curt Spectrum brake controller. You should be able to adjust the braking power by turning the knob clock wise. The LED lights will go from green to red. Is the brake controller not allowing you to adjust the braking power? I am happy to assist.
-- Etrailer Expert Heather A - 12/17/2021

- C51170

I bought this because I wanted a factory look. This was easy to install and looks great. You have to learn what the different colors and settings do but it’s not that difficult. Overall I am very happy with this brake controller.

I have thousands of miles on the trailer now. The brake controller has worked flawlessly. I have towed cars, ATVs and loads of lumber just set the controller for the load and it does the rest. Excellent product.
Doug - 04/26/2021

- C51170

I knew I wanted to have something like this due to the look, function and size. The package was small. Installed pretty easily with minimal headaches. I just watched the videos online to see how others did it and how to steer away from making damaging mistakes. The booklet was also very helpful to make everything fit as it should while putting the steps in order. As I pull a trailer 90% of the time, I wanted something to have the easy manipulation for the brakes yet have an aesthetically pleasing look. This does just that. Brakes on one setting. Adjustable on two other settings. Very quick. Although I did have to play with the settings to make sure it wasn’t jerking me in my seat every time I pushed the brake pedal, after a day, smooth sailing. I do recommend you seriously think about this brake controller. Ease of install and the application is perfect.

Wonderful! It has been a great tool!
Evan - 11/10/2020

- C51170

I've had the brake controller in use for over a year in my 2012 Nissan Frontier. The install was easy and took about an hour. My truck is a 2WD model so I mounted the controller in the plug that is used to select between 2WD and 4WD on vehicles equipped with 4WD. So the install look like factory.

- C51170

I installed it in a Jeep Gladiator. Easy install (the Gladiator is pre-wired so I just needed a harness). No problems at all!

- C51170

The Curt Spectrum Brake Controller works great for my 2008 Toyota Highlander. I mounted it on the front of the console armrest compartment behind the cup holders (facing forward). I was easily able to route the wiring out the bottom of the console and access the module under the drivers seat (be very careful installing the pins into the clip, they are very fragile). Then I ran the wires under the bottom edge of the console and out through the fire wall (Be very careful drilling your hole through the firewall. I caused some damage I had to have repaired}. Also, the help I had from Yolanda, making sure the kits I needed were compatible, was extremely important because I was leaving for a cross country trip later that week. She was wonderful and everything worked great for my trip. Thank you etrailer. I'm a regular customer and will remain so.

- C51170

This controller works very well. Installation on my Lexus GX460 was inconspicuous easy.and Once it was properly adjusted it did exactly what one would expect from a pricey brake controller.

- C51170

The first time I tried, I messed up the installation even though I watched the video (installation on a 2020 Colorado which was essentially identical to my 2018 Canyon). I had problems wiring the plug connector to the led display and broke off the end on one of the wires. I contacted Curt and they UPS'ed a new unit at no cost (fantastic support for their product). I was able to complete the wiring the second time but only after carefully studying the installation manual, especially, Page 6 and PAGE 7. The issue that I had to address was how to properly insert the wires into the plug connector. There are two figures, namely, Figure 2 on Page 6 and Figure 2 on Page 7 which illustrate what needs to be done. Figure 2 on Page 6 shows how the wires are to be inserted with "metal crimp facing down." You also see a little notch facing up. I believe that IT IS VERY IMPORTANT TO ALIGN THE WIRE IN THIS MANNER before trying to insert it into the connector. Even though the left hand side of Page 7 deals with uninstalling the brake control, Figure 2 of Page 7 illustrates how FAR the wires must be inserted for the system to work. Note that the wires must be inserted so that they are flush with left side of the connector when seen from above (with the latch up).

- C51170

2019 Honda Ridgeline RTL AWD— The Curt Spectrum C51170 controller and harness C51392 was exactly as I had read it would be! All connections hooked up as described and all connectors fit! The knob works as described but I have yet to hook up trailer to get response from the accelerometer! I’m sure the quality shown it will work fine! Only problem I had was access under the dash. Thanks Bill and etrailer! Pictures attached!

I really haven’t used it much after install except to test with empty car trailer. It worked well. Three or four people I have showed it to have been impressed! Thanks
George - 05/27/2020

- C51170

The compact remote control knob feature is a good plus for this product. Installation was really easy with the interface harness on the second generation Tacoma. I haven't had a lot of towing time with it but can offer the following insight. The control lights are easy to use and adjust. They appear to be dimmed with pulse width modulation so if your eyes are sensitive to it you might look at one before you buy. Hopefully they can go PWM-free at some point. The "white" color lamps appear as a mix of flashing red green and blue. Indicator lights are plenty bright in the daytime but the lowest dim setting is too bright. Perhaps this was done to minimize the PWM flashing at the dim setting. I had to locate the knob in the shadow of the steering wheel to keep the light out of my eyes at night. I've also noticed a single artifact light on many occasions after brake release (see pictures). So far the lamp color has been red, green, and blue however I have not yet seen a "white" one. One of these lights often come up in random positions on the dial. This lamp will continue to burn after I get out of the truck, and won't go out until I press the brake pedal again or push the knob. If I push the knob the output or sensitivity adjustment mode arc comes up briefly and it goes out after a bit (as it's supposed to). OEM brake control harness and grounding were sound with typical resistances around a milliohm or less. This controller is a considerable parasitic draw on the battery even with the lamps out and the ignition switch off. This could be an issue particularly if an artifact light is not noticed and the truck sits for more than a week(which mine sometimes does). A depleted battery made me look into this with a Fluke ammeter. You might consider pulling the fuse if the truck will sit or hook up a trickle charger. I tried to make contact with the manufacturer to see if they had any free convection requirements for air flow around the main module (air cooling at 100% duty cycle), and to understand what is going on with the controller and if there was something that could be done to fix the lights, perhaps a firmware update or something but never got any replies. The folks at etrailer maintained good communication and were excellent to work with but I don't feel the manufacturer is willing to support their product. This could be an excellent product if they can address these issues.

- C51170

So far so good. The install went well. The instruction were good. Install took about 4 hours, including a new 7 pin hook up at rear bumper. There is one thing that would have made for a cleaner install. We had to cut away the four pin connector and splice the wires in. if the male portion of the plug was provided, the install would have been nicer. Thanks for the product.

- C51170

I chose this controller as the main module fits out of sight and does not have to be aligned or leveled. I attached it to the parking brake bracket on our Pilot. The LED rotary control knob fits nicely on the dash and after inserting the cable through a small hole in the dash, connecting the plug was simple with the pins that were attached to the cable. What was confusing was the instructions do not mention there are two base plates - one for adhesive mounting to the dash and the other for drill mounting (what I did). I tried to snap the rotary knob into the base plate I mounted, but it would not fit. I found out that the rotary knob actually comes with the adhesive mount already attached and you have to use a small screw driver to pry it off so you can use the other base plate. Luckily Curt has an installation video on their web site that showed removing the adhesive plate. I generally do not start taking apart precision gear without some hint of what should be done. Curt also has a custom cable that plugs into this unit and the port on my Pilot. When I get our trailer I will be able to review the performance of this controller.

- C51170

Easy to use, install, & operate. I have to look in the mirror to make sure it's back there when I stop. 5 Stars from me Thanks etrailer

1 year later approximately 9000 miles and the brake controller works like a champ and has helped me avoid stupid drivers doing stupid acts.
John B - 01/13/2022

- C51170

After knocking my knee into my brake control for the last 20 years with the new GMC Savana I wanted something a little different. Technology has moved trailer brakes forward quite a bit and Etrailer has an immense amount of information! I original looked at the Tekonsha Prodigy RF Wireless Trailer Brake Controller but it would take up a valuable power outlet with the control unit but it's kind of trailer specific as the control mounts to the trailer you never know when you might have to tow another trailer and was leery of the control wandering around the console, Next up was the Redarc Tow-Pro Elite Trailer Brake Controller but did not like the control mounting options. Then ran across the Tuson DirecLink Lite Trailer Brake Controller crazy amounts of technology in this unit but again concerns over the remote so after lots of head scratching the Curt Spectrum seemed like the best choice. Easy install very small control box mounted easily with the included double stick tape under the dash. I moved my traction control button to the left where a blank filler was you have to cut a little piece of it off to get it into the hole as the are "keyed" to specific locations I guess but worked perfectly! I left enough slack in the connection so I can simply disconnect the harness if I am not towing for awhile as the blue indicator lights come on every time you hit the brake if its disconnected. Just installed it so I will send an update after our first trip with the new rig but I'm thinking it will work as described. Thanks again etrailer fast shipping great information!!!!

It has worked out great, I have over 4,000 miles of towing with it highly recommend it!!
Bob I - 01/13/2020

- C51170

Worked well in my Infiniti 2017 QX60 but install was not that easy. First unlike other etrailer products, I could not find an install video for my car. For other Infiniti owners out there, the brake controller connector is located along the wiring harness connected to the OBD connector. You cannot see it as it is lightly taped up, you just need to feel for it and pull it down. Secondly it is *capped*. The cap looks very much like the plug itself so don't be confused. Remove the cap and you can install. Make sure you get the right Curt adapter for your car. Secondly the install requires the user to insert the crimped controller wires into a connector for control module. There are videos on how to do this however it did not go as easy as shown. Maybe I had a defective part, but there is clearly only one way to insert the wires but I had to insert with significant force to get them in all the way. Once installed the unit worked fine with my 3,800lb RV trailer. A few nits: Occasionally the control knob will leave as one of its lights on after the car is turned off. Its happens occasionally and can be reset by pushing the brakes again but seems like a bug? Also the knob will *always* light up if you press the brakes even if you do not have a trailer attached. There is no way to turn this feature off and can be kinda annoying if you do not tow that much. Overall, works as advertised and like how it can be tucked away, but wish the install was better explained for my vehicle and didn't bother if there was no trailer attached.

- C51170

The installation went very quickly and the end result was very satisfying. The location of the switch on the dashboard makes it hard to spot as an aftermarket add on. The whole installation took 1 hour start to finish. I can't wait to tow a trailer so that I can get the Cuurt Spectrum Brake Controller calibrated and dialed in. Thanks etrailer! Thank Curt!

- C51170

I think that your brake controller is not made to plug into a 2021 Holiday Rambler. It has a six pin connector. The bad is I can't find an adaptor in Carson City. Your web site said this would fit! Now I leave tomorrow on a 8 day trip with no trailer brakes. This sucks!

Thank you for your review! I noticed that you said the C51170 would not fit your motorhome. In our fitguide, it is listed that you may need the universal wiring adaptor for Curt brake controllers, part # C51515
Universal Wiring Adapter for Curt Trailer Brake Controllers
to complete the wiring. Here is a link to that part. I hope this helps!
-- Etrailer Expert Brooke M - 06/30/2021

- C51170
by: - Awesome! Excellent customer service. Have dealt with them many times, Knowledgeable, Friendly and Helpful, great products at competitive prices. Highly Recommend. Curt Spectrum - Neat and clean, straight forward installation. Just make sure the wires to the plug connector are fully seated to the plug connector. Custom wire adapter makes installation plug and play. Picture is 2017 Silverado 1500.

- C51170

Excellent customer service from etrailer. Followed up until shipment reached canada.

- C51170

Excellent Product, especially if you want an OEM look. The heart of the system mounts out of sight behind your dash, while the control knob mounts wherever you can find a convenient spot. The Brake works great on my trailer as well as any that I have used in the past. So, the bottom line is that if you want a clean, OEM look and don't mind spending a little extra time with it's planning and installation, I highly recommend it,

We used the product and it worked well, but we have sold that Truck. I liked it for its OEM look and it performed well. It was a little challenge to install, but worth it in the end. Our replacement truck has a factory built-in controller.
Charlie - 06/27/2021

- C51170

Great product. Easy install in under 45 minutes to integrate into factory OEM harness. 2017 Land Ro er Discovery Sport with factory trailer tow package will be plug and play with this controller, and Curt custom wiring Adapter C51322. The factory brake controller integration harness is directly behind the OBDII connector on the driver’s side. Everything else is in place. Note: your factory OEM tow connection MUST be dealer activated in your vehicle. Without that activation, the body controller will not pass power to the brake module. There is ample space inside the dash on the left side, behind the left knee bolster to place the control module in a securable and protected location. This requires only 3 easy to remove panels, and 2 screws to reach. If oriented properly, the DIP switches are accessible in future by removing the dash side panel (zero tools required). There are multiple locations for the control knob. The look and style of the control knob fits perfectly with the design of the interior. Love the ability to use a drill or no-drill installation method. We haul our Forrest River travel trailer with this vehicle and previously used a time-based controller that “fought” with the vehicle’s integrated trailer stability control and anti-sway detection. This controller has solved this issue and gives complete control while integrating seamlessly with factory stability systems. Even with the output or sensitivity at high levels, this system still works perfectly with the vehicle trailer stability control. This was a vast improvement over our old time-based controller. Great function and fantastic look. For a non-OEM product, this truly does have an OEM look, function and ease of installation. Curt did a great job with this. My only nit is that both Curt and etrailer do not recognize the factory connection adapter harness as an option on the Discovery Sport. TIP: If you select the Land Rover Evoque (shares the same platform as the Discovery Sport) the options become correct for your Discovery Sport as far as factory adapter harnesses. Super fast delivery. Would be better if drop-ship items included an actual tracking number instead of only the user login web based tracking option. The web based tracking required logging in to monitor for delivery times. Some kind of automated text or email shipping updates for drop-ship items would make a great buying experience into a fantastic one.

- C51170

Nice little unit. Really like the fact you only have the control knob showing. Was hoping it was small enough to fit in extra spot on Tundra next to the traction control button. Was a little large but found a great out of the way really factory looking spot for it. Have not had a chance to hook up trailer yet but as far as install goes it was super easy using the pigtail plug. True plug and play. Instructions were very easy to read and understand.

- C51170

Installed on 2011 Toyota Sequoia - Wanted a controller solution that was not bulky or required drilling into the dash panel. This foot the bill. See photos - I was able to install without a single hole drilled into the dash panels. Mounted knob on left 4-switch panel which is easily accessible by driver and hidden away from passengers (so they are not bothered by the glow). VERY CLEAN LOOK.

Show More Reviews

Ask the Experts about this CURT Trailer Brake Controller

  • Parts Needed to Install Curt Spectrum Brake Controller in 2019 Toyota Tacoma
    Your 2019 Toyota Tacoma has a plug and play style of brake controller install port under the dash which will easily allow you to install the Curt Spectrum part # C51170. All you need is the adapter part # C51455. To reach the connector, first locate the notch in the access panel in the center of the dash, near the driver's side. Using a trim panel puller, carefully pry the panel out and undo the locking tabs to remove the panel. You will find the mating connector behind this portion...
    view full answer...
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  • Is Curt Spectrum Trailer Brake Controller A Good Option For 2020 Chevy Silverado 1500
    The Curt Spectrum Trailer Brake Controller part # C51170 and the custom wiring adapter part # C51525 is a great option for the 2020 Chevy Silverado 1500 because of its simple out of the way installation. The knob can be installed in any easy to reach location at any orientation. The main unit installs out of the way and utilizes the custom adapter plug for your truck to plug into the factory port. I have attached the measurements of both the main unit and the knob for you to get an idea...
    view full answer...
    Image 1 for Image 2 for
  • Easy to Install Brake Controller Recommendation for 2020 Jeep Gladiator
    For your 2020 Jeep Gladiator there is one brake controller that's going to provide a simple and easy install and that's the Curt Mobile Echo part # C51180. This basically just plugs into the 7-way of the vehicle and once synced to your phone is ready to go with one of the most advanced brake controllers out there. The Spectrum # C51170 would require hardwiring as there isn't an easy brake controller install port under the dash of your vehicle. I attached a review video for the Echo...
    view full answer...
  • Brake Controller Recommendation More Reliable than Curt Spectrum
    Curt should cover that. But the Curt controllers in general are just less reliable than the P2 part # 90885 that you mentioned. If I was going to recommend you the best option I'd say go back to the P2, see if Curt might warranty the controller, and then sell it used.
    view full answer...
  • Comparing Curt Spectrum and Redarc Tow-Pro Elite Brake Controllers for a 2019 Audi Q5
    I would be happy to compare the Curt Spectrum # C51170 with part # C51515 and Redarc Tow-Pro Elite # RED44FR brake controllers as well as make a recommendation for your 2019 Audi Q5. To establish a starting point, both controllers are unique when compared to standard brake controllers because they can be mounted virtually anywhere. This is due to the box that the control knob connects to which can sense the direction of movement without having to be in a specific orientation. The...
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  • Curt Brake Controller Plug for a 2020 Ford Explorer
    Yes, the Curt Custom Wiring Adapter for Trailer Brake Controllers part # C51322 will allow you to use a Curt brake controller like the Curt Spectrum Trailer Brake Controller part # C51170 on a 2020 Ford Explorer (All Models). I checked with Curt just to confirm that the Curt Custom Wiring Adapter for Trailer Brake Controllers is indeed correct for a 2020 Ford Explorer so you can be confident this is the correct harness. The plug will be located under the driver dash, near the center...
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  • Is Curt Spectrum Trailer Brake Controller a Good Option for 2018 Chevy Silverado 1500
    The Curt Spectrum Trailer Brake Controller # C51170 is a great choice for a brake controller in your 2018 Chevy Silverado 1500 because it is easy to use with the control knob you referenced and is a proportional controller so you will get smooth braking. To install it in your '18 Silverado you would also need the Curt Custom Wiring Adapter # C51451. The only other brake controller I recommend checking out is the Curt Echo Mobile Trailer Brake Controller # C51180 because this is even...
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  • Choosing Curt C51170 Spectrum or Redarc 331-EBRH-ACCV2 Tow Pro Brake Controller for 2019 Audi Q5
    The controllers are fairly similar in that they're designed so that the user interface is very unobtrusive. No more ugly box hanging on the underside of the dash that you can bang your knee on. Both controllers use a small knob that can be mounted pretty much wherever it would be within the driver's reach. Now, for the differences. The control knob of the # C51170 is quite a bit larger than that of the Redarc # RED44FR Tow Pro Elite, and it surface mounts. The Redarc would require a...
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  • Correct Wiring Harness for Curt C51170 Spectrum on a 2020 Jeep Grand Cherokee with Factory 7-Way
    To install the Curt Spectrum brake controller # C51170 that you referenced in your 2020 Jeep Grand Cherokee that has a factory 7-way all you need is the install harness # 3045-S and you'd be set.
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  • Installing Brake Controller on 2020 Jeep Gladiator without Splicing Into Brake Light Switch Wire
    As of this writing (10-2019) there is not yet a brake controller plug-in adapter available that allows for a plug-and-play installation on your 2020 Jeep Gladiator. With that being said, there are still a couple of ways you can install a brake controller (depending on the model controller) even if you aren't showing power on the brake light switch wire with the brake pedal depressed. First, to install a traditional brake controller like the excellent Curt Spectrum # C51170 you were...
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  • Recommended Brake Controller for a 2018 Thor Ace Motorhome
    For your 2018 Thor Ace Motorhome, I recommend using the Curt Spectrum Trailer Brake Controller part # C51170. The reason for this is because this unit is composed of two main parts, the control box and the output knob. The control box gets mounted out of site and then the output knob will get installed up on your dash for easy use and a very aesthetically pleasing look. The color output of the knob also helps with ease of use. Since your motorhome is on a Ford F-53 chassis, you can use...
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  • Wiring Harness For Curt Spectrum Brake Controller On a 2013 Toyota Tundra
    To install the Curt Spectrum Trailer Brake Controller # C51170 in your 2013 Toyota Tundra you will require one of two wiring harnesses. First the Curt Custom Wiring Adapter # C51362 will allow you to plug directly into the wiring port on your Tundra if your truck came with the factory tow package. This white connector is located just above the kick panel on the drivers side below the dashboard. If you do not have the factory tow harness the Universal Wiring Adapter # C51515 will...
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  • Correct Wiring Harness for Curt C51170 Spectrum Brake Controller on Ford Cutaway Van Chassis
    If your E450 Van Cutaway Chassis is a 2009 to 2020 model year, you'll need the Curt # C51432 harness to connect the # C51170 Curt Spectrum Brake Controller to the factory plug located behind the cubbyhole in the dash. If your van chassis is a different model year, please let me know and I'd be happy to make a recommendation. I've linked to a product description video that explains the features of the Curt Spectrum Brake Controller.
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  • How to Install Curt Spectrum Brake Controller on 2011 GMC Yukon with Factory 7-Way Connector
    While there isn't a direct plug for installing the Curt Spectrum Trailer Brake Controller # C51170, there are blunt cut wires under the driver's side dash of your 2011 GMC Yukon that you will connect the Adapter # C51515 to so that connecting the Spectrum is more of a plug-and-play installation. According to the online owner's manual for your Yukon you will connect the following wires from the adapter to the following wires on your Yukon: Blue - Dark Blue Black - Red/Black White...
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  • Availability of Curt Brake Controller Harness for 2020 Jeep Gladiator
    Curt doesn't yet offer a wiring harness for the 2020 Gladiator or Wrangler. What you could do is remove the black connector from the # C51170 Spectrum and the Tekonsha, part # 3073-P. You'd then wire the 3073-P to the Spectrum brake controller, color for color. Very easy. Another option would be the Curt Echo, part # C51180. The unit is wireless and would plug inline at the 7-way connector between the vehicle and the connector for the trailer. The unit would communicate wirelessly with...
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  • 7-Pole to 5-Pole Flat Trailer Connector Adapter For Towing Boat Trailer With 2020 Audi Q5
    We've got exactly what you need. You'll need a 7-way to 5-pole adapter like # A75TB. The adapter will pick up the signal from the reverse lamp pin of your 7-way and deliver it to the 5 pole connector on your boat trailer. When your Q5 is shifted into reverse, the lock-out solenoid on your hydraulic trailer brake coupler will close, preventing the brakes from actuating while you back the trailer.
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  • Can Curt Spectrum Install in 2019 Jeep Cherokee with Factory 7-Way
    Since you installed the factory 7-way setup on your 2019 Jeep Cherokee all you need to install the Curt Spectrum part # C51170 is the install harness # C51459 and you'd be set.
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  • Parts Needed to Install Curt Spectrum Trailer Brake Controller on 2020 Subaru Ascent
    Since your 2020 Subaru Ascent is already equipped with a factory 7-way connector, you will not need any additional parts other than the ones included with the Curt Spectrum Brake Controller part # C51170. There isn't a custom wiring adapter available from Curt for your Ascent, so you will need to hardwire the Spectrum controller in order to install it, or you can easily make your own adapter, using part # 3062-P. Basically, you'll cut off the black end of this adapter (the one that...
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  • Brake Controller Installation 2014 Volkswagen Touareg
    If your tow package includes the factory 7-way trailer connector on the rear bumper, you'll need a few parts from the dealer. You'll need one #1J0-972-782 housing and (qty. 2) #000-979-228-E wire/terminal assemblies. I've linked to the tech bulletin that explains the procedure as well as to an install video showing how those VW parts work. I've also linked to a demonstration video explaining how the Spectrum Brake Controller works.
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  • What do I Need to Install a Brake Controller on my 2020 Land Rover Discovery
    The Curt Spectrum Trailer Brake Controller part # C51170 can be installed on your 2020 Land Rover Discovery. You will need the Universal Installation Kit for Trailer Brake Controller part # ETBC7 and the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit part # 119250KIT. This will give you the 4-way flat you need to start then allow you to add on the 7-way connector needed to allow for the brake signal wire. The ETBC7 kit also has the...
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  • Curt Spectrum Lights On Overnight in my Chevrolet
    Good news is nothing is wrong with your system. I reached out to Curt and they have ran into this a few times with the newer model Chevrolet pickups. Basically the truck occasionally will run a systems check. This is a quick surge of power that gets sent around to verify everything. The Spectrum picks up that signal and gets confused when you open and close the door it is basically resetting it for lack of a better term. The LEDs that you see are just that lights similar to a phone...
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  • Should Curt Spectrum Brake Controller Show Lights on Display When Connected to Truck
    With a trailer disconnected the Curt Spectrum part # C51170 that you referenced should have the outer two lights flashing blue at idle or solid blue when the brakes are on. Since you used the correct install harness for this controller in your 2010 Ford F-150, part # C51436 you most likely have a blown fuse under the hood of the truck for the brake controller circuit. That would be only thing that would kill the circuits that power the controller.
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  • Comparing the Curt Spectrum Brake Controller to Redarc Tow-Pro Elite
    By all accounts the Curt Spectrum Trailer Brake Controller # C51170 works well and is easy to use and install on most vehicles. It is a brand new item so not a lot of feedback has come in on it. I did learn a few things though after speaking with our install team about this controller. First, compared to the Redarc controller # RED44FR, the Curt Spectrum is easier to install. It can be surface mounted meaning that drilling is not necessarily required (depends on how you run the wiring)....
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  • Hidden Brake Controller Recommendation for 2016 Ford Transit T350
    I would strongly recommend the Prodigy P2 part # 90885 over the Curt Spectrum part # C51170 if those are the two options you are considering since the Prodigy controllers have over the years consistently been much more reliable long-term than Curt. Now if you want a sleeker designed controller like the Spectrum but is also as reliable as the Prodigy I would recommend the Redarc TowPro Elite part # RED44FR. This gives you a similar style of proportional brake controller that only requires...
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  • Comparing the Curt Spectrum Brake Controller and Redarc Tow-Pro Elite for a 2016 Audi Q5
    Both the Curt Spectrum # C51170 and the Redarc Tow-Pro Elite # RED44FR are excellent brake controller options for your 2016 Audi Q5 but in comparison I recommend going with the Tow-Pro Elite over the Spectrum. Although both controllers can be used as proportional brake controllers (they activate your trailer brakes at the same time and with the same intensity as the brakes on your Q5) the Tow-Pro Elite can also be switched to "User Control" mode which means your trailer brakes will activate...
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  • Instructions for Mounting Knob of Curt Spectrum Trailer Brake Controller C51170
    I attached a page that I took from the install instructions for the Curt brake controller # C51170 that you referenced that covers the install of the knob of the brake controller. Basically a backing plate attaches to the dash with included hardware and then the knob attaches to it. I also attached a link the the complete install instructions to this page which are also available on the product page.
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  • Recommended Brake Controller and Pigtail For 2020 Honda Pilot With Factory 7-Way
    Great news Tom! There is a pigtail that you can use with the 2020 Honda Pilot to use the Curt Spectrum Trailer Brake controller part # C51170. You will need the Spectrum along with pigtail part # C51392 as confirmed by Curt which will plug into a port under the dash to install the brake controller. The Curt Spectrum is a great choice for the Honda Pilot because of it's dash-mounted control knob that can be installed anywhere in the cab (with reachable access) so it's discreet and looks...
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  • What Install Harness is Needed for Curt Spectrum in 2019 Chevy Suburban
    The install harness you need for the Curt Spectrum part # C51170 in your 2019 Chevy Suburban is the part # C51451 which plugs directly into the port on your vehicle and then into this controller for a simple install.
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  • Do Curt Spectrum and Redarc Tow Pro Elite Brake Controllers Have Boost Settings
    Actually the Curt Spectrum # C51170 that you referenced does have a boost feature that makes the braking action more aggressive using the sensitivity setting. In the second row of the picture I attached you can see this setting. The further into the red section you set the controller the more aggressive the braking action will be when sensing braking action. To switch between modes basically you just will press the center section until you see the three blue and three red lights that...
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