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

Part Numbers: C51170,C51451

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

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 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 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

Item # C51170

California residents: click here

Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In
part number: C51451

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


  • 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 beneath 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. The port is located in the wiring panel underneath the dash, to the left of the steering column, near the emergency brake pedal.

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.

51451 Curt Quick Plug Brake Control Adaptor Harness

California residents: click here

Customer Reviews

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

Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In - C51451

Average Customer Rating:  4.8 out of 5 stars   (178 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. Install your Curt electric trailer brake controller quickly and easily with this custom wiring adapter. Simply plug one end of the adapter into your controller and then plug the other end into the built-in port beneath your vehicle's dash.

- C51170
by: Casey08/17/2020

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. 863498

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by: Mike10/14/2018

Great product. Easy to install. Easy to setup and program. 574466

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by: Jay09/16/2019

Quick and easy install with the custom wiring adapter. Looks great too. 704629

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by: Christopher02/10/2020

Purchased this controller for use on my 2017 Toyota Tundra. It looks great after the install. I took a couple of hours to get it in from box opening to completion (with frequent distractions from children) but the manual was great and installation went smoothly. To clarify the issue with the blue lights I’ve seen as a complaint. When you start the car, it goes through it’s calibration procedure. If no trailer is attached, it blinks the two blue LEDs for a bit saying no trailer is detected. If you touch the brake pedals those blinking lights turn off. While you’re driving no lights are on. Then, every time you push the brakes the two blue LEDs turn on while the brake pedal is depressed to say you’re braking and it doesn’t detect a trailer. Honestly, I’m glad for those lights because if my trailer was connected and I saw those lights while braking I’d know there was something wrong with the connection. I put my unit directly to the left of the steering wheel so I’ll only see the lights when I lean over and look yet it’s easily accessible while in the drivers seat. Everyone was telling me to grab a P2 or P3, I’m glad I didn’t listen. This is nicely out of the way, easily accessible, clean and simple, and very capable unit with all the necessary capabilities one needs in a brake controller. 749473

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by: George05/26/2019

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! 647206

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


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by: Lars12/15/2019

Nice brake controller with hide-away module. Perfect fit for my Airstream Sprinter. Used the original clip location in climate control panel for controller location. Some modifications required but well worth the effort. 732487

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by: Jeffrey11/25/2019

Great Product! Easy to install with several installation options. Sensor box mounts anywhere with double sided tape. Control knob has several mounting options. Purchased it to drive across country to pick up a travel trailer. Temporary installation went easy and first time connection to the trailer had no problems. Instruction book was good and comes with a quick reference card to keep in the glove box. The only anomaly was that the cruise control on the vehicle (2007 Toyota Tundra) did not work when the trailer was connected. There are two switches on the sensor box though, one of which is to enable control of the tow vehicle brake lights by the trailer brake controller. Apparently when the switch is in the default position (control enabled), the unit puts out a voltage which makes the Toyota cruise control think the vehicle brake pedal is being pressed which automatically disengages the cruise control. Moving the switch to the other position solved the problem and cruise control works fine. Having that switch in the off position does not really have significant impact as I would not see that feature being used very often - the controller will not activate the tow vehicle brake lights when the manual control is pressed. You might use that to counter some sway event ( applying the trailer brakes only) but I hope that is something you do not have to do very often or hopefully never! It works as well as I could imagine any unit would - you can't really tell you are pulling a trailer when adjusted. Plus you won't mash your knees on some clunky box mounted to the bottom of the dash! Hopefully it is the last one I ever buy! 727768

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by: Johnboy Willis05/03/2019

Decided I wanted a high quality brake controller without the clunky box on the dash and this seemed like the best out there. Super easy install. I bought the extra cable for my Silverado and it all plugged in perfectly. I saw somebody complain about tiny connectors. Don't listen to them. This thing is excellent and the quality is clearly top tier. The set up was a breeze and on our first trip out I got it dialed in with no problems. Works better than my previous controller by far. 637364

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by: Evan11/09/2019

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. 724750

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by: Bob In Florida01/12/2019

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!!!! 597075

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


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by: Dan11/23/2019

I really like the finished look of this controller after it is installed (see before and after pictures attached)! I also like being able to finely tune it to my need using the power output and sensitivity adjustments. I do have a minor issue with connecting a trailer to my 2020 Jeep Gladiator, though. If I connect the trailer while the engine is running, the electronic stability control and engine start/stop services on the truck disable themselves. Turning the ignition all the way off an on again resolves the issue, as does having the engine off when I connect the trailer. Aside from that minor inconvenience, this controller works admirably and I would buy it for other vehicles. Installing was simple with the adapter for factory wiring. The most difficult part was identifying the location for the knob and taking the dash apart to install it properly. The finished appearance is clean and the only visible aspect of the entire system is the control knob. With the sensitivity and power controls on mid-level, the trailer tires were skidding on quick stops. Tuning the settings to have less sensitivity and less power quickly corrected that issue. I am quite happy with this controller! 727307

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by: Raul11/11/2019

Works good so far. My only complaint is, when trailer is not connected the blue LEDs still light up every time you hit the brakes, which is pretty bright inside the cab at night. 725121

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by: Logan09/24/2018

I've I stalked it but haven't used it yet because I thought the right adapter came with. I like the sleek fit to it so nothings hitting my knees etc. I recommend the design I stall forsure. Not sure how good it works yet like I said. I have a 2006 ford f150 fx4. 568517

For your 2006 Ford F150, youd need the # C51322
Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In
wiring harness. This will allow a plug and play installation. Once end will plug into the brake controller unit, the other into the gray tow package plug shown in the photo you provided.
-- Mike L - 09/25/2018


- C51170
by: James03/14/2019

I could not have imagined an easier, and more sleek, trailer brake controller to install. I put this into our 2019 4Runner, and it looks great, and I am not hitting my knee on the old style controller like we had in our previous tow vehicle. With the additional wiring harness that etrailer sells for the 4Runner it was simple plug and play. No need to struggle with finding correct wire lengths, just used some zip ties to have everything be tidy and clean. Thanks etrailer! 611935

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by: Dominick P.09/25/2019

We needed a brake controller for a Jeep Wrangler JL. If you've never been in one before, there is not a lot of space around the driver, so it would have been difficult to install a traditional brake controller where it wouldn't get in the way of legs. This was perfect. I really like that you have the option to mount the control knob over a hole if you want a clean installation with the wire hidden behind the dashboard, or to just use provided adhesive if you don't mind seeing the wire but don't want to drill a hole. (If you go the adhesive route, note that I'm not sure how easy it is to remove the adhesive. We drilled a hole.) If you do go the drilled-hole route, it does make installation more involved than most brake controllers. You probably have to remove trim panels from the dashboard to run the wire from the knob to the main box. But that's simply the price you pay for clean installation, and you can avoid that hassle if you go the adhesive route. The main box is very easy to mount. There are no restrictions on orientation and the box is fairly small, so it's easy to just screw or zip-tie it to anything up under the dashboard (so long as it's mounted securely--you don't want it to bounce or shake). As for ease of use: With just one knob and a few lights, it's not as dead simple as most brake controllers, but it's still pretty easy. Definitely easier than it seemed after I read the manual. Here's how it works: Pressing the knob cycles through the adjustment settings. There are three settings, and the color tells you which one you are on. White means you are adjusting brightness, bluish-pinkish means the sensitivity, and greenish-yellowish means the maximum braking level. Then tap your brakes (or wait 10 seconds) to go back to normal mode. Hold the knob to manually activate the brakes. That's really all there is to it. One minor quibble: I noticed that the lights sometimes get a bit "confused" and one of them will stay lit up in a random color. When this happens, the brakes themselves are working fine, it's just the light is mistakenly lit. Tapping the brakes fixes it. My only other complaint is that the lights are pretty bright at night. There is a brightness adjust setting, but even at the lowest setting it's still pretty bright. It doesn't bother me much, but my father-in-law does find it annoying. Overall, it's a very nice product. 707361

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by: Gary10/13/2018

Was an easy install for my 2018 Grand Cherokee with the addition of the specific cable adapter. I was able to secure the main unit under the dash on-top of the diagnostic port bracket and then run the wire for the dial up the drivers side of the dash so that it is concealed once the door is closed. The dial now sits on-top of the left side of the dash by the windshield pillar. I wanted to make this a temporary install incase I traded the truck in the near future. I have not hooked up a trailer yet so can not give a review on how well it works. 574127

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by: Wayne08/25/2018

I was looking for a unit that was out of way and would look like it belonged in the cab of the Chevy Colorado pickup. The Curt Spectrum control was easy to install under the dash and out of the way. The LED knob went on the dash with the wires going through the dash out of sight. 557904

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by: Matthew05/17/2019

Fits perfect if you want the more factory install look. Easy to mount and the control box is out of site with nothing to bash you knee into under the dash. Haven’t hauled my trailer yet but, I like how clean the finished product looks 642918

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by: Richard S C04/03/2019

Honda Ridgeline 2019 Install Plan to tow an RPOD 195 Travel Trailer as soon as I pick it up Simple Installation Didn't need to remove dash to install, as free space behind this location. Knob on lower left of Dash. Module Tie Wrapped to the Parking Brake Bracket under the Dash. Used the C51392 Wiring adapter to connect the Brake Controller to the Truck. Pictures of Dash Install only. Haven't functionally tested yet as I am waiting on Delivery of the Trailer. 616735

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by: Fred06/10/2019

When installing the control knob I could not use the screw mount base. The epoxy ( or what ever it is) on the back of the knob assembly that covers the wire connection kept the knob from snapping into the mount. I had to use the other mount to install the knob, hopefully it will stay in place. 655996

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by: Robert08/06/2019

I could have bought for the same price the one that plugs in series between your 7-way, but I liked the more permanent solution and didn't want to control it from my smartphone. Very pleased with the factory like look in my Nissan PRO4-X. 681352

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by: Scot06/19/2019

Great product and easy to install with harness, looks OEM stock! 660129

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by: Great Product09/08/2019

Ordered about 1 year ago. It has worked great. Looks great and easy to install. Takes a little getting use to it. Looks very stylish in my 2013 Ram. It goes perfect with the inside trim. 699336

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by: Luther05/04/2019

No trouble hooking it up with the plug and play connector,took about 1/2 hr and works great 638208

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by: Roger K09/23/2020

Part was delivered the next day and was just what i ordered... 889496

Show More Reviews

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

  • 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 # 331-EBRH-ACCV2, 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
    view full answer...

  • 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...

  • 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...

  • 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
    view full answer...

  • 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 # 331-EBRH-ACCV2 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
    view full answer...

  • 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...

  • Curt Spectrum Trailer Brake Controller on a 2019 Subaru Ascent
  • You will have to hardwire the Curt Spectrum Brake Controller part # C51170 to your 2019 Subaru Outback Wagon but it is a pretty simple process. You will need to first start with a 4-way confirmed as a fit for your vehicle. For that you'd want the Tekonsha part # 118467 which is a plug and play style of install. From there you would need to convert the 4-way to a 7-way so that you can install the brake controller. For that you will want the Brake Controller Install Kit and 7-Way Adapter
    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 # 331-EBRH-ACCV2 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.
    view full answer...

  • 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
    view full answer...

  • 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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  • 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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  • 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.
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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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  • 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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  • 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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  • 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 # 331-EBRH-ACCV2. This gives you a similar style of proportional brake controller that only
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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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  • Brake Controller Solution for 2010 Lexus GX-460 That Does Not Require Modifying Dash
  • Before getting into install locations for the knob of the Curt Spectrum part # C51170 you might be best off with the Curt Echo Mobile brake controller part # C51180 instead as this controller plugs into the 7-way at the rear of your vehicle and once you sync your phone to it you are ready to tow without needing to wire anything or modify your vehicle in any way. But back to the knob location for the could mount it near the AC controls on the center console like in 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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  • Curt Brake Controller Wiring Adapter for a 2006 GMC Sierra
  • We do have a plug-in adapter for your 2006 GMC Sierra, but the Curt # C51451 that you referenced is a fit for Chevy Silverado and GMC Sierra pickups starting in 2014. For your 2006 Sierra you want the Curt # C51352 instead. This adapter will plug into the junction box beneath your vehicle's dash as is demonstrated in the attached photos.
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  • Where Does a Brake Controller Plug In on a 2014 GMC Sierra 1500
  • On your 2014 GMC Sierra 1500 there is a junction box with a black cover on it located on the driver's side floorboard, way in the back, to the left of the brake pedal. There should be an empty spot to plug in the wiring harness located in the upper left corner. I have included a link to a video that should help. It is a different harness but it plugs into the same spot.
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  • Does Curt Brake Controller Install Harness part # C51451 Fit 2018 Chevy Silverado 2500HD
  • Yes, the Curt brake controller install harness part # C51451 that you referenced is a confirmed fit for your 2018 Chevy Silverado 2500 for installing a Curt brake controller like the Curt Triflex part # C51140 which would be a great option.
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  • How Does Brake Controller Install in 2014 GMC Sierra 1500 Using Factory Install Harness
  • The brake controller jumper wire you found in the glove box can be used to wire in the brake controller you have. I am not sure which controller you have but basically you'll plug the harness into the port under your dash for the brake controller install and then you'll wire it color for color to the brake controller's wiring and it will be wired in and ready to work.
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  • Curt Brake Controller Wiring Harness for 2018 Chevy Suburban
  • The Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In # C51451 is a fit for your 2018 Chevy Suburban if you already have the factory tow package with the factory 7-way trailer connector. If you do not have the factory 7-way, then you will need the Replacement Custom Multi-Tow 7-Way and 4-Way Trailer Connectors # 30955 and will hardwire the wires present under your dash to the Universal Wiring Adapter for Curt Trailer Brake Controllers # C51515.
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  • Brake Controller Wiring Harness for 2015 GMC Sierra 1500 and Curt TriFlex Brake Controller
  • For your 2015 GMC Sierra 1500 and Curt TriFlex brake controller # C51140 you will need wiring harness # C51451 to plug the controller into your truck. I have linked videos and instructions for both parts for you.
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  • Brake Controller Install Harness and Brake Controller Recommendation for 2015 Chevy Silverado 1500
  • Yes, the Curt brake controller install harness part # C51451 that you referenced will allow you to install a Curt brake controller in your 2015 Chevy Silverado 1500 like the Curt TriFlex part # C51140.
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  • Wiring Harness to Plug in a Curt Venturer Brake Controller to a 2002 GMC Yukon XL Denali
  • We certainly do! For your 2002 GMC Yukon XL Denali you will need wiring harness # C51342 to plug in your Venturer brake controller # C51110. I have included a link to a video review of the harness for you.
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Info for these parts were:

Expert Research:
Michael H
Expert Research:
Jameson C
Written by:
Laura H
Updated by:
Sarah W
Updated by:
Kristina F
Updated by:
Isabelle B

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