





Trailer Brake Control Electric Trailer Brakes Module Box Controller 1‑4 Axle
Model: 8508211Brake Control Unit
Mounting hardware and bracket
The REESE Towpower BRAKE-EVN brake controller offers advanced proportional braking by applying brake pressure to match the vehicles deceleration rate. Proportional braking gets you get smoother stops that traditional time based controls. The boost feature gives the ability to apply more initial braking at the onset of stopping when towing heavier loads. When adjusted properly for your load, proportional brake controls can even extend the life of your vehicles brakes. The large LED display is easy to see when adjusting the control to handle the weight of your loaded or unloaded trailer. The BRAKE-EVN brake control can handle up to brake 4 axles and offers a simple plug in installation option, so be sure to get the proper factory harness for your vehicle. The perfect choice for light or heavy trailer loads.
Brake Control Specs:
Thank you for choosing Reese made by same people that brought you Tekonsha and Draw-Tite the most powerful manufacturers of electric trailer brake control systems. Manufactured by the same people that brought you Reese, Draw-Tite and Hidden Hitch all of our products come with standard lifetime warranty and support. Our brake controls easily install on your Car Truck Van and SUV. For custom applications on Ford F150 F250 F350 E Series Van Expedition Toyota Tundra Tacoma Chevy Silverado Tahoe GMC Sierra Nissan Titan Frontier please choose one of our 2-Plug wiring adapters recommended below. These adapters will simply plug into the back of the brake control and the other end plugs into a matching plug on your truck. There is no splicing or worry involved, a very easy process. We have adapters for other vehicles as well. The brake control itself always comes with a 1-plug adapter out of the box, which you can splice into any vehicle. Getting a 2plug adapter will only easy your installation and avoid any sort of splicing. All parts in our store are sold at a discount. If you have any questions please do not hesitate to give us a call at 702-374-8999. We will match or beat anyones price.
$86 67 $118.75 27% OFF
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Product Details
- Brand: Reese
- Model: 8508211
- Includes: Electric Trailer Brake Controller
Specification | |
Manufacturer | Reese |
Part Number | 78081 |
Display Type | Indicator Light Only |
Solid State Construction | Yes |
Type | Proportional Inertia Based |
Self Leveling | No |
Number of Axles | 1 to 4 |
Housing | Black Plastic |
Warranty | 5 Year |
Mounting Hardware | Included |
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Description
Brake Control Unit
Mounting hardware and bracket
The REESE Towpower BRAKE-EVN brake controller offers advanced proportional braking by applying brake pressure to match the vehicles deceleration rate. Proportional braking gets you get smoother stops that traditional time based controls. The boost feature gives the ability to apply more initial braking at the onset of stopping when towing heavier loads. When adjusted properly for your load, proportional brake controls can even extend the life of your vehicles brakes. The large LED display is easy to see when adjusting the control to handle the weight of your loaded or unloaded trailer. The BRAKE-EVN brake control can handle up to brake 4 axles and offers a simple plug in installation option, so be sure to get the proper factory harness for your vehicle. The perfect choice for light or heavy trailer loads.
Brake Control Specs:
Thank you for choosing Reese made by same people that brought you Tekonsha and Draw-Tite the most powerful manufacturers of electric trailer brake control systems. Manufactured by the same people that brought you Reese, Draw-Tite and Hidden Hitch all of our products come with standard lifetime warranty and support. Our brake controls easily install on your Car Truck Van and SUV. For custom applications on Ford F150 F250 F350 E Series Van Expedition Toyota Tundra Tacoma Chevy Silverado Tahoe GMC Sierra Nissan Titan Frontier please choose one of our 2-Plug wiring adapters recommended below. These adapters will simply plug into the back of the brake control and the other end plugs into a matching plug on your truck. There is no splicing or worry involved, a very easy process. We have adapters for other vehicles as well. The brake control itself always comes with a 1-plug adapter out of the box, which you can splice into any vehicle. Getting a 2plug adapter will only easy your installation and avoid any sort of splicing. All parts in our store are sold at a discount. If you have any questions please do not hesitate to give us a call at 702-374-8999. We will match or beat anyones price.
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Trailer Brake Control Electric Trailer Brakes Module Box Controller 1-4 Axle Install Notes
Installation Instructions for Electronic Brake Control
Product Information:
- Model: Electronic Brake Control for 2, 4, 6, & 8 Brake Applications
- Part Number: N8508211
Components of the Brake Control:
- A. Output (Gain) Control
- B. Boost Control
- C. Manual Slide Control
- D. Bracket Mounting Holes
- E. LED Display
Package Includes:
- (1) Brake Control Unit
- (1) Mounting Bracket
- (4) Self-Tapping Mounting Screws (#6 x 3/8")
- (1) Warranty Card
Tools Required:
- Drill with 1/8” bit
- Wire Crimping Tool
- Probe-Type Circuit Tester
- Wire Cutter/Stripper
- Phillips Screwdriver or 1/4” Nut Driver
Wiring Connections:
- Black Wire: Vehicle Power
- White Wire: Vehicle Ground
- Red Wire: Stoplight Switch
- Blue Wire: Trailer Brakes
Step-by-Step Installation:
Step 1: Selecting a Mounting Location
-
Choose a location that is:
- Secure and solid for mounting.
- Easily accessible to the driver.
- Clear behind the surface to avoid damaging wiring or components when drilling.
-
Use the bracket as a template to mark hole locations.
Step 2: Mounting the Brake Control
- Drill holes at the marked locations using a 1/8” drill bit.
- Secure the bracket using (2) self-tapping screws.
- Mount the brake control unit to the bracket using the remaining screws.
Step 3: Wiring the Brake Control
-
Follow the wiring instructions:
- Black Wire: Connect to a constant 12V power source using a 30A auto-reset circuit breaker.
- White Wire: Connect to a solid vehicle ground.
- Red Wire: Connect to the stoplight switch wire.
- Blue Wire: Connect to the trailer brake output wire.
-
Ensure all connections are secure and properly insulated.
Adjusting Power to the Trailer Brakes:
-
Connect the trailer to the tow vehicle.
-
With the engine running, hold the Manual Slide Control to the left and set the Output/Gain Control to approximately 5.0.
-
Drive at 25 mph on a dry, level surface.
-
Fully apply the Manual Slide Control:
- If the brakes lock up: Reduce the Output/Gain.
- If braking is insufficient: Increase the Output/Gain.
-
Repeat until braking force is just below wheel lock-up.
Boost Settings:
The Boost feature increases brake sensitivity with three levels:
- b.1: Starts braking at 14% power.
- b.2: Starts braking at 28% power.
- b.3: Provides the most aggressive braking for heavy trailers.
To Adjust Boost Settings:
- Press the Boost Button to display the current setting.
- Use the + or - buttons to adjust.
Manual Control:
- Location: Right side of the brake control.
- The Manual Slide Control applies trailer brakes without activating vehicle brakes.
- Slide left to apply braking force manually.
- The power level can be monitored on the LED display.
LED Display Information:
Indicator | Meaning |
---|---|
Green | Trailer connected. |
Red | Brakes applied. |
Flashing | Wiring issues or short circuit detected. |
Troubleshooting:
Problem | Cause | Solution |
---|---|---|
No LED Display | No power or ground connection. | Check wiring connections. |
Brakes Too Aggressive | Boost or Output/Gain set too high. | Reduce settings. |
Trailer Brakes Not Responding | Insufficient power output. | Increase Gain setting. |
Flashing Display (2 per second) | Short circuit or overload detected. | Inspect trailer wiring and connections. |
Brake Adjustment Guide:
- Raise and secure the trailer with jack stands.
- Remove the brake backing plate cover.
- Adjust the brake shoes outward until the wheels are hard to turn.
- Back off slightly until the wheels spin freely with a slight drag.
Safety Notes:
- Always test trailer brakes at low speeds.
- Do not exceed the vehicle's Gross Combined Weight Rating (GCWR).
- Regularly inspect and adjust trailer brakes every 3,000 miles.
Technical Assistance:
For technical support and assistance, our team of experts is available to help.
You can reach our tech support by visiting www.trailerjacks.com or calling 877-869-6690.
Warranty Information:
- Limited Warranty: Covers defects in materials and workmanship.
- Excludes misuse, improper installation, and normal wear and tear.
For complete warranty instructions, please download the full installation PDF.