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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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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 (217)
  • 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   (217 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

The controller works great when hooked up to the trailer. Install looks clean and much nicer than any other controller. Very simple to use. Only flaw, and I own 2 of these in different trucks that do the same thing, is when not hooked to a trailer sometimes when you pick the brake petal, the lights on the controller stay lit up until you hit the brakes again. It has happened once where it stayed on and I got out of the truck and left it for a few weeks, not needing the truck, and ran the battery dead.

I spoke to Curt about this issue. They told me the Curt Spectrum Trailer Brake Controller light stays on. If you have a vehicle that will sit for an extended period of time, they recommend using a battery maintainer like the Duracell Battery Charger and Maintainer - AC to DC - 6V12V - 2 Amp Part # DU27FR
Duracell Battery Charger and Maintainer - AC to DC - 6V/12V - 2 Amp
-- Etrailer Expert Thomas M - 01/28/2022

- 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

Controller works great to control trailers. Dimmer control does not go low enough when you use the brakes during night driving the led's blind you. It does some goofy things with the leds when you hit the brakes sometimes random color leds stay on until you hit the brakes again. keep the cheat sheet handy you may not remember what different color setting mean.

Thousands of miles later works great. Really sensitive to wet or shorted plug.
Shawn - 02/01/2022

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

- C51170

This is an excellent trailer brake controller. It works as expected. The only thing I would change would be to make the braking mechanism adjustable when only using the manual feature of the braking system. If you want to stop the trailer only using the trailer brake it will send maximum input to the brakes.

- 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

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

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

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

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

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

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

Great Controller - just a small rotary dial showing. I recommend mounting it a little lower because the LEDs at the lowest setting are still too bright. It would be distracting at night time. The one quirk about this unit is sometimes it loses it's setting and it goes to full power. So, now I am in the habit of resetting my settings after I start the car and go. It's hard judging the setting from the LED because they lights bled over. So, I just dial it back and count the clicks.

It is still working great after one year.
Robert J - 02/23/2022

- 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

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

I bought this one because I wanted a freedom of locating the small actuator on the dash. This part worked well. The small actuator mounted nice next to the steering wheel. At some point the LEDs started flashing on it even when I was not in the truck... I sold the vehicle with it. Now I use the Prodigy II and although it is big and clunky under the dash, I really like the LCD display showing my exact voltage to the brakes and the codes.

- C51170

Just brake light on truck¦ no power lights on controller knob either found controller wires twisted in pig tail on rear of controller board sharp solder on back of board punctured wire in controller cable. Once I straighten conductors on back n rerouted through dash, it eliminated the short. All set Tx!!!!

- 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

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
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

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

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!

Show More Reviews

Ask the Experts about this CURT Trailer Brake Controller

  • Where to Access Brake Signal for Curt Spectrum Brake Controller in 2010 Mercedes-Benz ML350 BlueTec
    To correct the unwanted braking action from your Curt Spectrum # C51170 caused by the 3.6V monitoring signal generated by your 2010 Mercedes-Benz ML350 BlueTec you'll need to access the brake light signal at a location other than at the brake light switch. You can tap into the circuit at the CHMSL (center high-mount stop light) or at one of the two main brake lights and run that wire back to the controller's RED input trigger wire. My contact at Curt confirmed this and that you do not...
    view full answer...
  • Do the Lights Flash on the Curt Spectrum Trailer Brake Controller with Trailer Unconnected
    The two blue lights (see photo) on each side of the Curt Spectrum Trailer Brake Controller part # C51170 will only display when a trailer is disconnected and the brake pedal is applied. You cannot turn this feature off but you can dim it with the included dimmer feature. You can also mount the knob out of direct eyesight which is more or less what it is designed for. If you can tell me what vehicle you will be installing the Spectrum brake controller on, I would be glad to check if there...
    view full answer...
    Image 1 for
  • Trailer Disconnected Indictor When Trailer Is Disconnected From Curt Spectrum Brake Controller
    I will be happy to assist you with the issue you are having with the Curt Spectrum Trailer Brake Controller # C51170. I reached out to my contact at Curt and they indicated that the disconnected light only comes on when you hit the brakes with your trailer disconnected. Curt advised that there is no way to disable this feature without disconnecting the entire unit.
    view full answer...
  • Dimensions of Components in Curt Spectrum Trailer Brake Controller C51170
    On the Curt Spectrum Trailer Brake Controller # C51170 the round base of the rotary knob component measures 1-3/4-inches in diameter and has a depth of 1-1/2-inches. The main control box component measures 3 x 3-1/2-inches overall and has mounting holes spaced apart on center at 3/4 x 2-3/4-inches. I made a photo with these dimensions which is linked for you. The Spectrum does have a 10-LED display but the controller output is not limited to only 10 specific power and boost settings.
    view full answer...
    Image 1 for
  • Dimension of Bracket for Curt Spectrum Trailer Brake Controller
    I went out to our warehouse to measure the bracket for the Curt Spectrum Trailer Brake Controller # C51170 that you referenced and found that it has an outside diameter of just under 2 inches (1-15/16 inches to be exact). I have attached the image you sent with this dimension labeled that you can also use for reference.
    view full answer...
    Image 1 for
  • Is There a Way To Turn the Light Off On the Curt Spectrum While Not Towing
    The Curt Spectrum Trailer Brake Controller part # C51170 will illuminate even without a trailer connected that is correct. If you don't wish to see this light each time you hitch the brakes without a trailer attached then you will either need to mount the control knob in a location that is still within reach but not in direct eyesight or you can unplug the harness that connects the control knob to the control box. I cannot recommend you splice into any of the wires to make your own sort...
    view full answer...
  • 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...
    view full answer...
  • What Colors Will Curt Spectrum Brake Controller Light Up with Brake Pedal Pressed
    The Curt Spectrum # C51170 will light up from green to red (with the trailer connected) depending on what power setting you chose. This will be the case whether you are parked or heading down the road. I confirmed this with my contact at Curt. I've also attached a photo showing what the display will look like as well as a review video you can check out.
    view full answer...
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  • Does Curt Spectrum have Manual Override Feature
    The Curt Spectrum # C51170 does have a manual override that maybe you weren't familiar with. If you press and hold the knob the manual override feature is active. When you press the button the brakes will begin to apply similar to a time delayed brake controller and the braking power will ramp up.
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  • Is There a Setting to Use Curt Spectrum Brake Controller with EOH Brakes
    The Curt Spectrum Trailer Brake Controller part # C51170 is compatible with electric-over-hydraulic trailer brakes, there is no setting that needs to be applied for this to work. It will automatically sense the type of brakes used and make the necessary adjustments needed to ensure compatibility.
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  • Curt Spectrum Trailer Brake Controller Single Red LED Light When Braking
    It sounds like your Curt Spectrum Trailer Brake Controller # C51170 is working properly. You are not getting an error code, but the number of red lights should increase as more brake power is asserted. The actual number of red lights that appear depends on how you have tuned the controller and it may depend on the inertia as well because it is a proportional controller. If you need more braking pressure then simply adjust the setting. I've attached the installation instructions to assist...
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  • Flashing Red and Yellow Lights of Curt Spectrum Brake Controller
    The flashing red and yellow lights of the Curt Spectrum Trailer Brake Controller # C51170 means you have a short on the blue brake wire. Since you just installed the controller and your 7-way that means it is almost certainly on the trailer side. This is virtually always due to a damaged, frayed, or exposed wire to the trailer brakes so you will need to trace the wires to the brakes and find the one that is injured. I have also added a link below to a help article on brake controller...
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  • Can The Curt Spectrum Trailer Brake Controller C51170 Be Disabled When Backing Up Trailer?
    The Curt Spectrum Trailer Brake Controller - 1 to 4 Axles - Proportional - Dash Mount # C51170 will only apply the brakes to your trailer when you press and hold the knob to engage the manual override, or apply the brakes to your tow vehicle. As long as you are not applying the brakes you will have no issues backing up. I included a video of the # C51170 for you to take a look at.
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  • How To Use Curt Spectrum Trailer Brake Controller C51170 With Electric Over Hydraulic Brakes
    I reached out to my contact at Curt and there is actually no specific mode the Curt Spectrum Trailer Brake Controller # C51170 you were looking at needs to be in to work with electric over hydraulic brakes. You will just hook up the trailer and adjust the settings the same as you would for a trailer with standard electric brakes, making sure you get the output and sensitivity right for that trailer. I included a video of the # C51170 for you to take a look at.
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  • Battery Drain with Curt C51170 Spectrum Brake Controller
    I'd be interested in why they think the Curt # C51170 Spectrum brake controller caused the problem. Brake controllers are directly connected to the vehicle battery, so the controller will always be receiving a very minimal amount of power. Once the vehicle is shut off, and the controller doesn't sense any vehicle motion for 10-15 minutes the controller goes into a 'sleep' mode. During this sleep mode, the vehicle would need to be left unattended for 3-4 months before the battery would...
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  • Curt Spectrum Trailer Brake Controller Initial Set Up
    The Curt Spectrum Trailer Brake Controller # C51170 is a proportional controller that uses an inertia sensor to adjust braking voltage that is sent to the trailer brakes. It has no way of reading the amount that you push on the brake pedal when the vehicle is not moving and will only send a little amount of power since it feels that there is no braking inertia. This prevents the trailer from pulling the vehicle to a hard stop when at very low speeds. As you begin to drive with the trailer...
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  • Does the Curt Spectrum Trailer Brake Controller Draw Power While Not In Use
    The Curt Spectrum Trailer Brake Controller part # C51170 only draws a small amount of power while not in use. It would only be able to kill the battery from this draw after several months of inactivity. The reason it still draws power while not in use is to store any save settings. Therefore, if you were to install some sort of in-line switch to cut power you would have to go through the setup procedure each time power is restored.
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  • Troubleshooting Intermittent Connection Message of Curt Spectrum Brake Controller
    Try cleaning off the pins of your 7-way connector on your tow vehicle with sandpaper. A lot of times some corrosion or dirt can get on the connector which can trick the controller into thinking a trailer is connected.
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  • Can A Brake Controller Be Turned Off So It Doesn't Drain Vehicle Battery
    The fact that the Curt # C51170 has a direct connection to battery is not unique to the Curt Spectrum brake controller, they all install in that manner. This is purposely done as a safety measure, so the user can't forget to turn on the brake controller before they tow. The good news is that after a short period of inactivity (varies from 10-20 minutes) the controller will go into a sleep mode, at which point they only draw a miniscule amount of power. Unless the vehicle will be left unattended...
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  • Why Am I Not Getting Any Power To A Curt Spectrum Controller After Installing On A 2019 Canyon
    If the Curt Spectrum # C51170 isn't lighting up when a trailer is connected to your 2019 GMC Canyon, there will be a few things you need to check. First, and this will sound obvious but it actually happens more than you would think, you will need to make sure all the plugs are fully seated and snapped together. A loose or incomplete connection can definitely cause it to not function. With that out of the way, you will need to test the black wire going into the controller. This should...
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  • Troubleshooting Brake Controller Not Activating with Brake Pedal
    Make sure the brake lights of the vehicle are still working...especially the third brake light. If they stopped working then the issue is a blown brake light fuse. If they are still working it's probably the connection of the red wire of your brake controller to the stoplight switch which I'd check again to make sure it's making a solid connection.
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  • Is Curt Spectrum Brake Controller Good Choice for Horse Trailer
    The Curt Spectrum brake controller part # C51170 would be a great option for towing a horse trailer. Since it uses an inertia sensor to sense how hard you apply the truck brakes and then applies a relative amount on the trailer brakes it will provide smoother braking which your horses will appreciate.
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  • Does Curt Spectrum Brake Controller Remember Brightness Settings
    Since the Curt Spectrum Trailer Brake Controller # C51170 retains a connection to a power source when installed it remembers all settings you pick and does not require you to reset the brightness.
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  • Brake Controller for 2008 Dodge Durango with Factory Wiring Harness for Tow Package
    You need to purchase both the Curt Brake Controller # C51170 and the Curt Wiring Harness # C51332 for your Dodge Durango as they are sold separately. This allows you to plug directly into the port that comes with the tow package and is located directly under your dash.
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