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2010 - 2021 Mercedes-Benz Sprinter 2500
Confirmed to Fit









Always the correct part
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Always the correct part
We know our products
Quality Products
Free Shipping!
Includes mounting hardware & plug & play harness
Knob outside diameter is 1.9"
Patent #10,960,860
Includes mounting hardware & plug & play harness

Warranty: Limited Lifetime
Installation Time Exact (Minutes): 0
The CURT Spectrum trailer brake controller provides powerful brake operation while maintaining a clean, consistent OE look and feel on the dash of your vehicle. It is comprised of a main module and a separate user interface. This interface is a simple rotary knob with a push-button and ten tri-color LEDs to control and monitor all trailer brake activity. It also features a triple-axis accelerometer for highly responsive, smooth stops on any grade. The separated module and interface of the Spectrum brake controller allow it to integrate with the vehicle unlike any other. The main module can be mounted behind the dash and completely out of sight. The separate rotary knob provides a sleek, subtle interface that mounts on the dash of the vehicle wherever desired. It features ten LEDs with three colors each (red, green and blue) to indicate trailer brake activity and power adjustment. The rotary knob and integrated push-button allow for simple and effective operation of the control settings and manual adjustment. The Spectrum trailer brake controller offers superior safety and helps protect the life of your vehicle and trailer with its advanced triple-axis accelerometer. This integrated circuit detects the motion of the vehicle and trailer when making stops and applies the precise amount of brake power for maximum efficiency and effectiveness. The three axes of the circuit also enable the brake control to compensate when going up or down a hill. Like most CURT brake controllers, the Spectrum installs using one of our vehicle-specific quick plug harnesses. It also has automated leveling and calibration capabilities to simplify and speed up the installation process. The Spectrum trailer brake controller comes with mounting hardware for a complete installation.

CURT offers a variety of high-quality trailer hitches and accessories for select vehicle models. Find the perfect fit for your towing needs at TowUniverse.
CURT, a Lippert brand, offers a complete line of towing products and is the leading manufacturer of custom-fit trailer hitches. We offer the broadest selection of custom-fit hitches, and each one is designed, welded, and coated in Wisconsin.
CURT is also a leader in flat towing products, as well as 5th wheel, gooseneck, and weight distribution hitches, ball mounts, electrical components, cargo solutions, and other towing accessories.
For everything from passenger cars and vans to full-size pickups and SUVs, CURT is 'The First Name in Towing Products®.'
Experts available to answer your questions
Call 888-634-94941 compatible vehicles
| Year | Make & Model | Notes |
|---|---|---|
| 2010 - 2021 | Mercedes-Benz Sprinter 2500 | — |
The 2010-2021 Mercedes-Benz Sprinter 2500 CURT Venturer NEXT Time-Delay Trailer Brake Controller for 1-3 Axles #51116 (Part #CURTBC1973) fits the following vehicles: 2010-2021 Mercedes-Benz Sprinter 2500. Always verify your specific year, make, and model before ordering.
Yes, the 2010-2021 Mercedes-Benz Sprinter 2500 CURT Venturer NEXT Time-Delay Trailer Brake Controller for 1-3 Axles #51116 (Part #CURTBC1973) is designed to fit the 2010-2021 Mercedes-Benz Sprinter 2500.
The 2010-2021 Mercedes-Benz Sprinter 2500 CURT Venturer NEXT Time-Delay Trailer Brake Controller for 1-3 Axles #51116 (Part #CURTBC1973) fits 2010-2021 Mercedes-Benz Sprinter 2500 models. The 2021 model year is the last year covered by this part number. For newer models, check for an updated version.
The 2010-2021 Mercedes-Benz Sprinter 2500 CURT Venturer NEXT Time-Delay Trailer Brake Controller for 1-3 Axles #51116 (Part #CURTBC1973) Refer to the included instructions for installation details. Basic hand tools are typically all you need.
The manual does not specify which vehicle makes, models, years or generations this brake control harness fits. Contact CURT product support at 877-287-8634 or visit curtmfg.com to confirm fitment for your specific vehicle before purchasing.
Part 51535 is a custom brake control harness designed to connect a brake controller to your vehicle's brake control system. It includes a mating connector that plugs into your vehicle's factory brake control connector located under the driver seat.
The manual requires that the vehicle ignition be off and not in the 'ON' or 'ACCESSORY' positions before installation. It does not explicitly state whether the battery must be disconnected. For safety, contact CURT product support at 877-287-8634 before beginning installation.
You will need a ratchet, a panel trim removal tool, and a T-25 Torx bit. The T-25 is used to remove the four screws holding the vehicle battery cover in place. CURT provides a tools reference guide at curtmfg.com/trailer-hitch-installation.
The green 4-pin brake control harness connector is located underneath the driver seat. You may need to slide the driver seat as far back as the seat rails allow, or temporarily remove the driver seat, to access it.
Removal of the driver seat may be required to gain access to the green 4-pin brake control connector underneath the seat. First, try sliding the seat as far back as the seat rails will allow. If you cannot reach the connector, you will need to remove the seat.
The vehicle battery cover is located on the floor of the vehicle just in front of the driver seat. It is held in place by four screws that you will remove using a T-25 Torx bit in Step 3. You may need to temporarily remove a floor mat or carpet to access it.
1. Turn off the vehicle ignition. 2. Slide the driver seat back and locate the green 4-pin brake control connector under the seat. Disconnect it carefully. 3. Install the custom brake control harness, ensuring all locking tabs are secure. 4. Remove the battery cover using a T-25 Torx bit. 5. Route the harness from under the seat into the battery box and up through the dashboard to your desired brake controller location. 6. Install and test the brake controller per its manual. 7. Reinstall the battery cover and all removed items.
Plug the brake control adapter into the mating connector on the brake controller first. Then attach the harness to the vehicle connectors, ensuring all locking tabs are fully in place. The manual emphasizes that connectors must be securely attached with all locking tabs engaged to function properly.
Route the custom brake control harness out from under the driver seat and into the battery box. Continue routing it up through the dashboard to your desired mounting location for the brake controller. The manual does not specify the exact path through the dashboard.
Yes. The 51535 is a harness that connects your vehicle to a brake controller. You must install and configure the brake controller separately following its own manual. The harness alone does not control trailer brakes.
Do not lay tools across the positive battery terminal (typically marked with red covers or a red '+' symbol). Doing so can cause a ground short, leading to sparks and/or electrical shocks. Be careful when working near the battery during installation.
Do not exceed the product rating or the tow vehicle lamp load rating, whichever is lower. Exceeding either rating can damage the brake control system and compromise trailer braking safety.
After installing and testing the brake controller per its manual, test the harness for proper function by using a test light or by connecting a properly wired trailer. The manual does not provide detailed testing procedures beyond these methods.
Temporary removal of a floor mat or carpet covering may be required to access the battery cover on the floor in front of the driver seat. Check before beginning installation.
The manual does not specify vehicle applications. Contact CURT at 877-287-8634 or curtmfg.com to confirm fitment before purchasing.
You need a ratchet, panel trim removal tool, and T-25 Torx bit. See curtmfg.com/trailer-hitch-installation for a full tools reference guide.
The manual requires the ignition to be off but does not explicitly state whether battery disconnection is required. Contact CURT product support at 877-287-8634 for safety guidance.
Do not exceed the product rating or tow vehicle lamp load rating, whichever is lower. Do not lay tools across the positive battery terminal to avoid short circuits and electrical shock.
Test for proper function using a test light or by connecting a properly wired trailer. Follow the brake controller manual for its testing procedures.





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