Trailer Brake Control for 99‑02 GMC Sierra 1500 2500 3500 Electric Trailer Brakes Module Box Controller 1‑4 Axle
Model: 8508211 3025-9Brake Control Unit
Mounting hardware and bracket
Vehicle specific Plug and Play Wiring Adapter
Fits The Following Vehicles
1999 - 2002 GMC, Sierra 1500, All Styles
1999 - 2002 GMC, Sierra 2500, All Styles
2001 - 2002 GMC, Sierra 3500, All Styles
Brake Control Specs:
| Part Number | 8508211 |
| Brand | Reese |
| Type | Proportional |
| Axles | 1 to 4 axle trailers |
| Features: |
|
| Installation Instructions |  |
2-Plug Wiring Asapter Specs:
| Part Number | 3025 |
| Brand | Tekonsha |
| Warranty | 1 Year |
| Installation Instructions | |
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.
Partial list of fitment years: 99 00 01 02 1999 2000 2001 2002
$93 55 $113.57 18% OFF
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Product Details
- Brand: Reese
- Model: 8508211 3025-9
- Includes: BRAKE-EVN Proportional Brake Controller for Trailers with 1-4 Axles, Trailer Brake Controller Custom Harness
Compatibility Chart
Brake Control Unit
Mounting hardware and bracket
Vehicle specific Plug and Play Wiring Adapter
Fits The Following Vehicles
1999 - 2002 GMC, Sierra 1500, All Styles
1999 - 2002 GMC, Sierra 2500, All Styles
2001 - 2002 GMC, Sierra 3500, All Styles
Brake Control Specs:
| Part Number | 8508211 |
| Brand | Reese |
| Type | Proportional |
| Axles | 1 to 4 axle trailers |
| Features: |
|
| Installation Instructions | |
2-Plug Wiring Asapter Specs:
| Part Number | 3025 |
| Brand | Tekonsha |
| Warranty | 1 Year |
| Installation Instructions | |
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.
Partial list of fitment years: 99 00 01 02 1999 2000 2001 2002
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Trailer Brake Control for 99-02 GMC Sierra 1500 2500 3500 Electric Trailer Brakes Module Box Controller 1-4 Axle Install Notes
Installation Instructions for Electric Trailer Brake Control Wiring Adapter
Part Number: 302500
Tools Required:
- Circuit Tester
Step-by-Step Instructions:
Step 1: Locate the Vehicle’s Electric Junction Box
- Locate the vehicle’s black Electric Junction Box:
- Inside the vehicle, underneath the dashboard, to the left of the steering column, just above the carpet.
- Remove the junction box cover to expose the connection points.
- Find the electric trailer brake connection point:
- Located in the top row, second slot from the left.
Step 2: Plug in the Brake Control Adapter
- Plug the brake control adapter into the mating connection point in the Electric Junction Box.
- Use a circuit tester to verify that the adapter has battery (+) power supplied.
Step 3: Install Additional Wiring if Power Is Not Supplied
If power is not present at the Electric Junction Box, follow these steps:
A. Vehicle Brake Control Feed Wire (Blue):
- Open the vehicle’s hood and locate the black Electrical Center Box on the driver’s side.
- Remove the lid and cover of the Electrical Center Box.
- Locate the blue brake control feed wire. This may require temporarily removing the vehicle’s support brace.
B. Vehicle Battery (+) Power Supply Wire (Red):
- In the same location, find the red battery (+) power supply wire.
- Attach and route the power wire as specified in the brake control manufacturer’s instructions.
- Install an in-line fuse or circuit breaker to protect the circuit.
Step 4: Connect the Brake Controller
- Plug the brake control adapter into the vehicle’s electric brake control harness connector.
- Follow the brake control manufacturer’s installation instructions for wiring, mounting, and securing the brake controller.
Warnings:
- Circuit Overload:
- Do NOT exceed the lower of:
- Manufacturer’s towing rating, or
- Maximum Capacity: 4 axles / 8 brakes (24 amps).
- Do NOT exceed the lower of:
- Overloading circuits may cause fires or electrical damage.
- Always follow the vehicle owner’s manual and brake control installation instructions.
Wiring Overview:
- Brake Control Feed (Blue): Sends brake signal to trailer brakes.
- Battery Power Supply (Red): Provides fused power to the brake controller.
- Ground: Grounds the controller to the vehicle.
- Stop Lamp Switch (Input): Signals braking input to the brake controller.
Final Notes:
- Verify all connections are secure and wires are properly routed away from sharp edges or heat sources.
- Use a circuit tester or connect a trailer to confirm proper operation.
- Periodically inspect the wiring system for damage or loose connections.
End of Instructions
Installation Instructions for Electric Trailer Brake Control Wiring Adapter
Part Number: 302500
Tools Required:
- Circuit Tester
Step-by-Step Instructions:
Step 1: Locate the Vehicle’s Electric Junction Box
- Locate the vehicle’s black Electric Junction Box:
- Inside the vehicle, underneath the dashboard, to the left of the steering column, just above the carpet.
- Remove the junction box cover to expose the connection points.
- Find the electric trailer brake connection point:
- Located in the top row, second slot from the left.
Step 2: Plug in the Brake Control Adapter
- Plug the brake control adapter into the mating connection point in the Electric Junction Box.
- Use a circuit tester to verify that the adapter has battery (+) power supplied.
Step 3: Install Additional Wiring if Power Is Not Supplied
If power is not present at the Electric Junction Box, follow these steps:
A. Vehicle Brake Control Feed Wire (Blue):
- Open the vehicle’s hood and locate the black Electrical Center Box on the driver’s side.
- Remove the lid and cover of the Electrical Center Box.
- Locate the blue brake control feed wire. This may require temporarily removing the vehicle’s support brace.
B. Vehicle Battery (+) Power Supply Wire (Red):
- In the same location, find the red battery (+) power supply wire.
- Attach and route the power wire as specified in the brake control manufacturer’s instructions.
- Install an in-line fuse or circuit breaker to protect the circuit.
Step 4: Connect the Brake Controller
- Plug the brake control adapter into the vehicle’s electric brake control harness connector.
- Follow the brake control manufacturer’s installation instructions for wiring, mounting, and securing the brake controller.
Warnings:
- Circuit Overload:
- Do NOT exceed the lower of:
- Manufacturer’s towing rating, or
- Maximum Capacity: 4 axles / 8 brakes (24 amps).
- Do NOT exceed the lower of:
- Overloading circuits may cause fires or electrical damage.
- Always follow the vehicle owner’s manual and brake control installation instructions.
Wiring Overview:
- Brake Control Feed (Blue): Sends brake signal to trailer brakes.
- Battery Power Supply (Red): Provides fused power to the brake controller.
- Ground: Grounds the controller to the vehicle.
- Stop Lamp Switch (Input): Signals braking input to the brake controller.
Final Notes:
- Verify all connections are secure and wires are properly routed away from sharp edges or heat sources.
- Use a circuit tester or connect a trailer to confirm proper operation.
- Periodically inspect the wiring system for damage or loose connections.
Attention:
This is a summary of the installation procedure. For complete installation instructions, including diagrams and detailed information from the manufacturer, please download the full installation PDF.
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.
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.
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