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  1. Trailer Brake Controller
  2. Hayes
  3. Electric
  4. Time Delayed Controller
  5. Up to 2 Axles
  6. Indicator Lights
Hayes Syncronizer Trailer Brake Controller - 1 to 2 Axles - Time Delayed

Hayes Syncronizer Trailer Brake Controller - 1 to 2 Axles - Time Delayed

Item # HA81725
Our Price: $49.14
You Save: 38%
Trailer Brake Controller
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Shipping Weight: 0.71 lbs
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This time-delayed brake controller has a straightforward design that makes it easy to use. Includes an LED indicator and manual override. Activates brakes with a preset intensity. Great Prices for the best trailer brake controller from Hayes. Hayes Syncronizer Trailer Brake Controller - 1 to 2 Axles - Time Delayed part number HA81725 can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (73)
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Hayes Trailer Brake Controller - HA81725

  • Electric
  • Time Delayed Controller
  • Up to 2 Axles
  • Hayes
  • Indicator Lights
  • Dash Mount
  • Under-Dash Box
  • Automatic Leveling
  • Up to 360 Degrees

This time-delayed brake controller has a straightforward design that makes it easy to use. Includes an LED indicator and manual override. Activates brakes with a preset intensity.


  • Brake controller activates trailer brakes with preset intensity
  • Adjustable power output lets you select the amount of braking force
    • Thumbwheel located on front of module for easy access
  • Red LED indicator on front of unit illuminates when trailer's brakes are applied
    • Light glows brighter as power output increases
  • Slide-bar manual override is within easy reach for controlling trailer sway or stopping in emergencies
  • Built-in safeguards protect your vehicle and your trailer
    • Current limiter protects vehicle from shorts in the trailer wiring
    • Hazard flasher immunity prevents pulsing of the brakes when flashers are activated
  • Dependable solid-state construction
  • Quick and easy installation with no mounting restrictions
    • No need to mount level - install anywhere at any angle
    • Mounting bracket and hardware included
    • Plug-in, vehicle-specific brake control adapter (sold separately) available for select vehicles to reduce installation time
  • Made in the USA


  • Application: trailers with up to 2 axles (4 brake assemblies)
    • Compatible with electric brakes only
  • Dimensions: 5-1/4" long x 3-1/8" wide x 1-1/4" tall
  • 3-Year limited warranty

Built-In Controls on the Syncronizer

Syncronizer Controls

Power Output Control

Braking output is the maximum amount of power that will be applied to your trailer's brakes. How much braking output you need is determined by the weight of your trailer; a heavier trailer will need more power to bring it to a stop. You want to set the braking output as high as you can without locking up the brakes. Once you've set up the brake controller the first time, you shouldn't need to adjust the settings until the trailer load changes, you switch trailers, or road conditions change. Use the thumbwheel on the left of the module to change your settings.

Red Indicator Light

The red LED indicator light illuminates when the trailer brakes are applied. This light glows brighter as the power output to the trailer brakes increases.

Slide-Bar Manual Override

The Hayes Syncronizer keeps the manual override within easy reach on the front of the module, great for stopping sway or controlling your trailer's momentum in emergencies. Push the slide-bar lever to activate the trailer's brakes and brake lights without you having to apply the brakes on your tow vehicle, perfect for limiting trailer movement while you're cruising.

Hayes Syncronizer review

Quick, Simple Installation

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

If your vehicle already has a plug-in brake controller wiring harness, just connect the unit 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.

Installation Accessories

See also'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 20-amp circuit breaker (sold separately) may be required for installation.

Time-Delayed Braking

What is time-delayed braking

The Hayes Syncronizer comes equipped with time-delayed braking. Every time you apply the brakes in your vehicle, a signal is sent - via the brake switch - to the Syncronizer. The controller then sends power out to your trailer brakes to activate them with an intensity set by you, at a rate determined by you. The amount of braking power (output) can be adjusted to suit your preference, the road conditions, the type of trailer, and the weight of your load. To determine which levels are best for your application, test your towing setup and choose what feels right.

81725 Hayes Synchronizer Electric Brake Controller - Time Based

Installation Details HA81725 Installation instructionsAlternate Instructions HA81725 Installation instructions

Customer Satisfaction Score:

Customer Reviews

Hayes Syncronizer Trailer Brake Controller - 1 to 2 Axles - Time Delayed - HA81725

Average Customer Rating:  4.7 out of 5 stars   (73 Customer Reviews)

This time-delayed brake controller has a straightforward design that makes it easy to use. Includes an LED indicator and manual override. Activates brakes with a preset intensity.


No threaded inserts in unit and screws for attachmen, guess you get what you pay for

Etrailer Expert

Katrina D.


I am sorry that you are missing the hardware for this brake controller. Can you please confirm what you are missing?

Randall S.


@KatrinaD Hello, yes the brake controller, they are screws, self tapping, but no threads in controller. They just tap into plastic which is easy to strip out.
Etrailer Expert

Katrina D.


@RandallS Oh I see now, Randy. Thank you for this information. I have looked into the brake controller installation, and unfortunately, that is just how they arrive out of box (with no threaded inserts). I am sorry this information was not made clear on the product page. Are you actually missing the screws? Or did they arrive, but it wasn't clear that the threads needed to be added to the controller upon arrival?


Nice product and very easily installati on.


Super fast delivery and easy plug and play installation. Would highly recommend


Great price, no delay as it came the same day as promised. Feel very comfortable dealing with etrailer !


Super easy to install and the additional information they provided for my specific vehicle made it possible for me to have every piece necessary for a seamless installation.


Splicing the wires was no problem. Instructions were good. The only recommendation that I will give is that you trash all screws with flat screw driver heads. I also opted for bolts, nuts & washers for attaching the bracket.


I think it will be a good brake controller, I have not had a time delayed on before.


works great


Original supplied item was defective, however Hayes customer service immediately sent another unit and it works great. With the addition of a small removable slip in bracket for the console of my 2012 GMC 1500 Crew Cab and the wiring adapter, I can simply plug and play when I need the controller as opposed to a permanent installation that I have in my other pickup.


Installation was simple and straightforward. Took less than 30 minutes from start to finish.


Looks good!


Works well. I like the delayed brake activation, it seems to be a smoother transition. The custom harness makes installing this controller easy and FAST. Love buying Made in the USA products and has a lot of them.


easy to install. Brakes tested good to trailer. I used self taping screws to mount brackets, rather than the bolts and nuts that it came with.It was to difficult to get my hands in position to use bolts and nuts (no big deal).


Fit perfectly. Followed instructions and it works as it should. Great product at a great price.


Installed in 10mins in 2018 ram 1500 ecodiesel, have not used with trailer yet. Seems good for price, mounting bracket could be made a little better. Good service from e trailer


Good controller at a good price. Works as expected. Fast shipping at standard rate. This controller was installed in an 08
Sprinter camper with the help of the on line video from etrailer.


This is the 2nd one of these I’ve bought. I like the time delay application to the brakes. Always will try to buy products made in the USA. The price went up since I bought this same controller 1 1/2 years ago.


Was easy to install and adjust. Works great applying breaks to my single axle dump trailer.


The trailer seems to be holding up just fine. It was a good investment for my small business and I'm thinking about buying another from you.


Installed in 10 minutes. Works excellent and combined with the wiring adapter was a simple plug and play.


deliverd on time. and plugged right in thanks


super fast delviery great product pluged right in



Best controller out there


First time user on eTrailer. Great website and easy to use. With my parts selected the site suggested the quick connect wire kit for my vehical. This made installation a breeze.


My Hayes Brake controller was as described, Easily wired,mounted reasonably price,


Great service! Fast delivery! Would order from again!

Show More Reviews

See what our Experts say about this Hayes Trailer Brake Controller

  • Recommended Hayes Trailer Brake Controller Wiring Harness for 2003 GMC Sierra SLT with Tow Package
    For your Hayes Syncronizer Trailer Brake Controller # HA81725 on your 2003 GMC pickup with tow package, you will want wiring adapter # HA81780-HBC. This will plug into your junction box beneath your vehicle's dash. That is all you will need as you stated.
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  • Harness Needed to Install Hayes Brake Controller in 2017 Ford F-150
    All you need to install the Hayes Syncronizer part # HA81725 in your 2017 Ford F-150 is the custom install harness part # HA81794-HBC which plugs in under the truck dash and you'd be set.
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  • Brake Controller Install Harness for Hayes Synchronizer in a 2014 Chevy Silverado 1500
    To install the Hayes Brake controller part # HA81725 in your 2014 Chevy Silverado 1500 only requires you to use the install harness part # HA81798-HBC which is a confirmed fit.
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  • Why Is My Hayes Brake Controller Only Getting 10v At the Brakes
    The Hayes Syncronizer Trailer Brake Controller # HA81725 requires 12v to operate properly so since you're only getting 10v at the brakes that leads me to believe there is a wiring issue somewhere. You're going to need to go through your wiring, testing incrementally for voltage while looking for any damaged or exposed wires. If that's all good, I'd double check the wire is 10 gauge # 10-1-1 because smaller wire can cause also voltage drop. It's also a good idea to check your ground...
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  • What Does a CL or cl Code Mean on a Brake Controller
    I did some research and found that on some brake controllers, the "cl" code stands for Current Limit. This indicates that the brake controller has sensed a power requirement greater than its recommended output. This could result from an intermittent short to ground, a faulty brake magnet, or too many brakes connected to the controller. Some brake controllers like the Hayes Engage, # HA81760, are designed for 2 - 6 brakes (up to 3 axles). But others like the Hayes Synchronizer, # HA81725...
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  • Uninstalling Hayes Syncronizer Brake Controller From 2014 Ford Explorer
    To disconnect the Hayes brake controller you can simply unclip the wiring connection behind your trailer brake controller and tuck it out of the way. Then you can remove the brake controller from it's mount and either discard it or sell it. It will not in any way effect the braking on your vehicle. It only captures the brake light signal and then sends power to a trailer with brakes. Removing it will have no impact on your vehicle but only on your trailer towing ability.
    view full answer...
  • Recommended Pigtail for a Hayes Syncronizer Brake Controller on a 2012 Chevy Tahoe
    Though the 2012 Chevy Tahoe will have all the wires run for a brake controller, there is no port present under the dash for one to plug directly into. That being said, we do have a plug that will attach to the one on your Hayes Syncronizer # HA81725. The # HA81789-HBC will have bare wires on the end so you can connect to the wires under the dash.
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  • Plug and Play Wiring Adapter For Hayes Syncronizer Brake Controller On 2022 Chevy Silverado 1500 LTD
    The Custom Wiring Adapter # HA36FR will allow you to connect your Hayes Syncronizer Trailer Brake Controller # HA81725 to your 2022 Chevrolet Silverado 1500 LTD.
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  • Which Brake Controller Adapter for 2017 Nissan Pathfinder with Hayes Synchronizer
    You can use a Hayes Synchronizer # HA81725 in your 2017 Nissan Pathfinder using the plug and play adapter Custom Wiring Adapter for Hayes Brake Controllers - Dual Plug # HA81786-HBC. This will be the plug that goes from the car to the controller.
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  • Troubleshooting Hayes Syncronizer Trailer Brake Controller
    That is not normal. The Hayes Syncronizer Trailer Brake Controller - 1 to 2 Axles - Time Delayed # HA81725 should not give off any smell and should not be activating the brakes enough to cause smell if installed and adjusted properly. I've attached a video of this installation for you to reference. When installed correctly, this unit should be adjusted for sensivity. This conroller has a red LED indicator on front of unit that illuminates when trailer's brakes are applied. This light...
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  • Brake Controller Compatibility with 2015 Audi Q7 TDI Prestige
    The Hayes Syncronizer Trailer Brake Controller -Time Delayed # HA81725 can be used on your 2015 Audi Q7. You will need to hardwire your controller, but I recommend using the wiring adapter # HA81789-HBC to allow you the quick connection so you can use this controller on other vehicles if desired. You will also need to use additional wiring as you pointed out. You will need to ask your authorized dealer for #1J0-972-782 housing (qty. 1) and #000-979-228 wire/terminal assemblies (qty....
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  • Parts Needed to Install Brake Controller in a 2016 Ford Transit
    To install a brake controller in your 2016 Ford Transit Connect tou will need to start with a 4-way (if you do not have one). For that you would want the # C56218. 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 part # ETBC7. I attached installation instructions and an install video for this product as well. For a brake controller I would recommend the Prodigy...
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  • Wiring Harness for Installing HA81725 Hayes Synchronizer Brake Controller on 1998 Ford E350 Van
    We offer the Ford-specific Hayes brake controller wiring harness as part # HA81783-HBC. One end of the harness plugs into the connector under the dash, the other plugs into the pigtail exiting the rear of the Hayes # HA81725 Synchronizer brake controller. The brake control connector on your E-series van is located either under the left side of the dash or next to the center console. It will be in the very corner where the floor board, firewall and the left kick panel come together. This...
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  • Does Hayes Syncronizer Brake Controller Have Time to Full Intensity
    The Hayes Syncronizer Trailer Brake Controller # HA81725 does not have a time from brake activation to full intensity. Reason is this depends on the amount of power you set the controller to.
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  • Brake Controller Wiring Harness For A 2009 Dodge Ram 2500
    The correct wiring harness that will connect the Hayes Syncronizer Trailer Brake Controller part # HA81725 to factory wiring harness on your 2009 Dodge Ram 2500 is the Custom Wiring Adapter for Hayes Brake Controllers part # HA81782-HBC. This a complete plug and play option that will not require hardwiring unless you do not already have a factory trailer connector installed, in that case you will need to use the hardwire wiring harness that comes with the Hayes Syncronizer Trailer Brake...
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  • How to Find the Brake Wire on a 2000 Chevrolet Express Van
    In order to find the brake wire under your dash, you are going to need a circuit tester like part # PTW2993. Then you are going to need someone to engage the brake on your 2000 Chevrolet Express Van as you use your circuit tester to see which is the brake wire. When you find the right wire, a light will glow on the circuit tester. The wires you need to test are the bundle of wires coming out of the back of the brake pedal stop light switch. Use the circuit tester to find the hot wire only...
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  • Wiring Colors for Kelsey Hays Brake Controller 81739
    Your old Kelsey Hays brake controller uses the standard wiring colors for brake controller install. The red goes to the stoplight circuit, the black goes to the 12 volt power supply, and blue goes to the trailer connector as it's brake output.
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  • Why Does Hayes Syncronizer Brake Controller HA81725 Not Light Up When Pedal is Pressed
    The display on the Hayes Syncronizer Trailer Brake Controller # HA81725 should illuminate both when you press the brake pedal and when you use the manual override lever. If it does not light up when you press the brake pedal then either there is a problem wit the red wire's connection to the brake light circuit or you have the power set so low that the display does not light up. The controller will apply full power with the manual lever but with the brake pedal it will illuminate only...
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  • Wire Harness Needed To Install A Hayes Syncronizer Trailer Brake Controller In A 2023 Ford Bronco
    There unfortunately isn't a plug-and-play wire harness to connect your Hayes Syncronizer Trailer Brake Controller # HA81725 to your 2023 Ford Bronco so you'll have to use the universal splice-in wire harness # HA81789-HBC. This harness will need to be wired in the follow order: Black: 12v power White: Ground Blue: Trailer brake output Red: Bronco cold side of Brake Light Switch If your Bronco is a base model without the signature LED lighting then the cold side of the brake light switch...
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  • Recommended Custom Wiring Adapter for Hayes Brake Controllers on a 2016 Ram 1500
    Yes, it will. The Custom Wiring Adapter for Hayes Brake Controllers item # HA81795-HBC will allow you to connect the Hayes Syncronizer Trailer Brake Controller item # HA81725 to your 2016 Ram 1500. The harness plugs in to the factory connector located above where you right leg would be as you're sitting in the driver's seat.
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  • Custom Wiring Harness for Hayes Brake Controller in 2017 GMC Sierra 1500
    Your Hayes Syncronizer Trailer Brake Controller - 1 to 2 Axles - Time Delayed # HA81725 is confirmed to fit your 2017 GMC Sierra 1500 using the custom wiring harness # HA81798-HBC. This adapter plugs into the port that is built into the electric junction box underneath your vehicle's dash. The black box is located to the left of the steering column, just above the carpet. To plug in the adapter, first remove the cover on the box. The adapter plugs into the first slot on the left, in the...
    view full answer...
    Image 1 for
  • Wiring Harness to Connect Hayes Syncronizer Brake Controller # HA81725 to 2005 Dodge Ram 1500
    The existing wiring harness you have used to connect your Hayes Syncronizer Trailer Brake Controller # HA81725 to your 2007 Dodge Dakota will also work to install this unit in your 2005 Dodge Ram 1500. The harness is part # HA81782-HBC and it plugs in between the hardwired connector at the back of the controller and the connection port under the dash on your Ram 1500. The Hayes Syncronizer brake controller # HA81725 is a time-delayed type as opposed to a proportional type brake controller....
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  • Red Light Not Illuminating On Hayes Syncronizer Trailer Brake Controller in 2002 Chevy Silverado
    The red light of the Hayes Syncronizer Trailer Brake Controller part # HA81725 should only illuminate when the vehicle's brakes are depressed which activates the trailer brakes. If your not getting the red light when you depress the brake pedal it doesn't sound like the brake controller has power. It sounds like you are using the hayes brake controller adapter wire part # HA81781-HBC, you may want to check the fuses in the Chevy to make sure all of the factory tow package fuses are present....
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  • Troubleshooting Cruise Control Not Working After Brake Controller Install
    Sounds like you connected the red (stoplight switch circuit) wire to the wrong circuit on your truck. When the cruise control on a vehicle starts acting up that is a tell-tale sign that the wrong circuit is being used for the red wire. What you want to do is use a circuit tester like part # PTW2993 to test the wires near the brake pedal to find the circuit that only sees 12 volts when the brakes are applied and none when the brakes are released. Correcting this should take care of both...
    view full answer...
    Image 1 for

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Info for this part was:

Employee Mike L
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Employee Sarah H
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Employee Lindsey S
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