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  1. Trailer Brake Controller
  2. Hayes
  3. Electric
  4. Proportional Controller
  5. Up to 3 Axles
  6. Indicator Lights
Hayes Energize III+ Trailer Brake Controller - 1 to 3 Axles - Proportional

Hayes Energize III+ Trailer Brake Controller - 1 to 3 Axles - Proportional

Item # HA81742B
Our Price: $89.94
Trailer Brake Controller
Shipping Weight: 0.67 lbs
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This proportional brake controller keeps towing simple with a straightforward design and user-friendly controls. Includes an LED indicator and a slide-bar manual override. Adhesive backing gives you the option of drill-free mounting. Great Prices for the best trailer brake controller from Hayes. Hayes Energize III+ Trailer Brake Controller - 1 to 3 Axles - Proportional part number HA81742B can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Hayes Trailer Brake Controller - HA81742B

  • Electric
  • Proportional Controller
  • Up to 3 Axles
  • Hayes
  • Indicator Lights
  • Dash Mount
  • Under-Dash Box

This proportional brake controller keeps towing simple with a straightforward design and user-friendly controls. Includes an LED indicator and a slide-bar manual override. Adhesive backing gives you the option of drill-free mounting.


Features:

  • Brake controller activates your trailer brakes in proportion to your vehicle's braking action
    • Automatically adjusts trailer's braking based on deceleration of tow vehicle
  • Simple controls keep your settings within easy reach
    • Gain setting lets you adjust the amount of power sent to the trailer's brakes
    • Slide-bar manual override allows you to control trailer sway or stop in emergencies
    • Deceleration sensor lever lets you adjust initial braking power and aggressiveness for smooth, safe braking
  • Red LED indicator lights up when brakes are engaged
  • Quick, simple installation with included bracket and hardware
    • Drill-free installation option with included adhesive tape
    • Optional universal wiring adapter (HA81789-HBC) sold separately for a plug-and-play installation
    • Plug-in, vehicle-specific brake control adapter (sold separately) can be used to reduce installation time on certain vehicles
    • -35-Degree to 90-degree mounting range - must be horizontally level
  • Made in the USA


Specs:

  • Application: trailers with up to 3 axles (6 brake assemblies)
    • Compatible with electric brakes only
  • Dimensions: 5-3/8" long x 3-1/4" wide x 1-3/8" tall
  • Mounting angle: -35 degrees to 90 degrees vertically
  • 5-Year limited warranty


Gain Setting for Braking Power

You can adjust the gain setting (also known as braking output) on the Hayes Energize III+ using the thumbwheel on the front of the module. This will set the maximum amount of power that will be applied to your trailer's brakes. You want to go as high as you can without the trailer brakes locking up. Typically, the gain is only readjusted when you experience changing road conditions or if you switch over from a heavy, loaded trailer to a much lighter, empty trailer, or vice versa. To get more power to your brakes, turn the wheel up. To get less power to your brakes, turn the wheel down.


Hayes Energize III+ Braking Output

The red LED indicator on the front of the module will light up when the brake controller is activated. This way you can keep your eye on your braking and be sure that it's working.


Sensitivity Adjustment with Deceleration Sensor Lever

Once you have the overall power set, you can fine-tune the power output by adjusting the sensitivity of the internal sensor. This controls the aggressiveness of your trailer's braking, meaning how quickly the brakes reach the maximum braking level. You can adjust this when you're towing heavy loads and you need more umph to bring your trailer to a stop. Your tow vehicle doesn't need that much power to brake in time, but your heavy trailer does. Boost gets the braking power to your trailer brakes faster and with more intensity so that it doesn't push your tow vehicle forward. To increase the sensitivity for towing heavier loads, move the lever away from you. For a lighter load, move the lever toward you.


Slide-Bar Manual Override

The Hayes Energize III+ comes with a built-in, easy-to-reach slide-bar manual override, great for stopping sway or controlling your trailer's momentum in emergencies. To engage the manual override, just push the slide-bar to the left, toward the center of the controller. This will 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.


Quick, Simple Installation

The Hayes Energize III+ is easy to mount wherever you want it. Simply use the bolts or the double-sided tape to secure the included mounting bracket to your dash, and then install the controller in the bracket.


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.


Because the Hayes Energize III+ operates with an internal inertia sensor, it must be mounted between -35 degrees and 90 degrees vertically. The brake controller also needs to be horizontally level and parallel with the direction of travel to function properly.


Installation Accessories

See etrailer.com's exclusive 7- and 4-way brake-control installation kit (ETBC7 - sold separately) if you don't already have a 7-way plug at the back of your vehicle


Note: One of the following will be required to ensure proper installation:

  • 20-Amp circuit breaker (9506P - sold separately) for 2- to 4-brake applications
  • 30-Amp circuit breaker (38630 - sold separately) for 6- to 8-brake applications

Proportional Braking

What is proportional Braking

The Hayes Energize III+ brake controller comes equipped with proportional braking to give you the best towing experience. Proportional braking means that your trailer brakes mimic your tow vehicle's brakes. If you slam on the brakes in your vehicle, your trailer brakes will activate with the same intensity; if you brake lightly, your trailer brakes lightly too. The trailer's braking is in proportion to your vehicle's braking. This saves wear and tear on the tires and the brakes on both your vehicle and trailer.


The Energize III+ uses a pendulum system to sense how your vehicle is braking so it can send the right amount of braking power to your trailer. It detects the inertia of your tow vehicle and activates the trailer's brakes to slow at the same rate. The result is uniform braking across your towing setup. No push-pull action - just smooth, proportional braking every time.



81742B Hayes-Lemmerz Energize III Plus Brake Controller - 1 to 3 Axles - Proportional

Replaces 81741B and 81745

Installation Details HA81742B Installation instructionsAlternate Instructions HA81742B Installation instructions



Customer Satisfaction Score:


Customer Reviews

Hayes Energize III+ Trailer Brake Controller - 1 to 3 Axles - Proportional - HA81742B

Average Customer Rating:  4.6 out of 5 stars   (118 Customer Reviews)

This proportional brake controller keeps towing simple with a straightforward design and user-friendly controls. Includes an LED indicator and a slide-bar manual override. Adhesive backing gives you the option of drill-free mounting.

by:

This controller was truly "plug&play". Installation was 30 min. Works perfectly. E-trailer has always been my go-to for all my truck and camper needs!

Terry

11/15/2023

This controller has been very reliable this past year. No problems with mounting or function. Would still recommend to anyone needing a quality,plug-and- play brake controller. SAFETY FIRST !!



by:

This is my second order with etrailer. Both experiences with your company have been very positive. The knowledge and friendliness -along with following up on orders and satisfaction have been much appreciated. Brittany, the customer representative, is a huge asset to etrailer.



by: 09/25/2023

Controller installed easily. Unit applies brakes ok. My big concern is the
lack of the voltage setting being displayed. This is first controller I have
worked with. Video says good back unit. Ok that it is. But if I had known what I know now, would have purchased unit with digital voltage setting. Setting wheel to same spot each use is causing me to go through setting process each time. There is a difference with brakes with unloaded and loaded trailer.



by:

Works like it should. Easy install. Other models will offer more features, but for a part time camper puller like myself, it does the job



by:

The controller is not at all smooth in applying brakes. very abrupt in braking, have tried adjustments and mounting with no improvement. Would not recommend.



by:

It continues to do its job flawlessly. Have not had a single concern with it while towing. It allows for manual application of braking "pressure", but except for testing it at low speeds to verify operation, I have not had to touch it at all while highway towing, as it achieves smooth, even stopping power. Still very pleased with the purchase!



by:

I opened the box and there was rattling around in controller. It was the f
Gsi. Dial!!! I Want my money back



by:

2001 Ford F-250. Plug and play. EASY!



by:

Works perfectly. 1 year and counting.



by:

Easy to install and great customer service. One problem: writing on instructions was so small I had to use magnifying glass to read it and my vision is 20/20. This needs to be corrected by manufacturer. Instead of tiny writing in several non English languages, print it so the vast majority of customers can actually read it. This would probably eliminat e many customers calling etrailer for help in installation.



by:

Remember the adage, "you get what you pay for"? Certainly applies here...I will never know if this unit was faulty when I received, or if it simply is poor quality. But the "gain" function on it does nothing, and therefore I can't dial in the sensitivity that is needed. Again, I don't know when/how it became inoperable, but I just ordered it's replacement. Am hopeful for a better experience...

Etrailer Expert

Jenny N.

11/16/2022

This controller does have a limited lifetime warranty against manufacturer defect. Customer Service will be in touch.



by:

Easy to install. Clear instructions.,Works great.



by:

work's great, thanks



by:

Great service good people to deal with



by:

The plug and play wire harness that I ordered for my pickup should have been 5-6 inches longer. Otherwise everything was fine.



by:

Appreciate the installation videos



by:

Nicole was outstanding in knowledge and patience with me. She helped me get through my mistaken order and get me the right brake controller and adaptor harness for my truck. I installed it in less than and hour and it is working great. She also made the return of the controller and harness a breeze.



by:

Perfect, exactly what I needed great price, fast delivery, easy installation. It only took about 30 minutes total. The hardest part was for an old man to get down that low in the floor well. Thanks again etrailer.



by:

This brake controller has worked great no problems at all I would recommend it to anyone using this style of brake controller.



by:

Got tip off Utube for the wiring harness adapter for a 2019 Ram. Installation was plug and play. We have a 26 ft camper we will be towing. Very easy install.

Richard

10/29/2020

Great! No complaints.



by:

Simple install with wire harness from etrailer, plugin, adjust, done. Works and does what I anticipated.



by:

Works but doesnโ€™t totally perform as 2012 stock dodge one.



by:

Best of the four brake controllers I've had so far in my truck. Easy to adjust on the fly if brakes are too strong or weak. Manual override felt solid unlike some controllers out there. The instructions could've been written a little clearer though. 4 prong square plug also fits Curt controllers if swapping. Overall nice controller for the money, should've bought this one first and saved the cash



by:

works great.



by:

super easy to install with the adapter. gain was set a tad high initially so be sure to turn it down first, then up until you get the gain you want.

Dennis L.

8/16/2021

Working well, I now have it in a different truck.


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118
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    In addition to the Hayes Energize III # HA81742B brake controllers, you'll need a # HA81783-HBC wiring harness for the 1999 Ford F550. The 2000 Chevy 1 ton and cab/chassis models weren't prewired for a brake controller until the 2001 model year, so you'd need to hardwire in the controller for that vehicle. You'll also need a # HA81789-HBC universal pigtail, unless you want to cut off the black connector on the controller. I'd recommend using the pigtail, as it would allow you to easily...
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    Since the trailer brakes are working when you press on the brake pedal, it sounds like there could be one of two things going on here. It could be something as simple as the connections inside the controller being dirty or dusty. Give the manual override button a series of pushes and let the button snap back up into place- we just want to try to dislodge anything that might be keeping the button from making a full connection to the internal parts that operate the manual override. If the...
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Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Jameson C
Expert Research:
Jameson C
Employee Joshua S
Video by:
Joshua S
Employee Jacob H
Video by:
Jacob H
Employee Samuel H
Video by:
Samuel H
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
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Employee Kathleen M
Updated by:
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Employee Wilson B
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Employee Hannah L
Updated by:
Hannah L
Employee Amanda K
Updated by:
Amanda K
Employee Laura H
Written by:
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Employee Cole B
Installed by:
Cole B
Employee Shane H
Test Fit:
Shane H
Employee Ryan G
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Ryan G
Employee Matthew B
Test Fit:
Matthew B

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