Recommended Brake Controller for a 2025 Thor Quantum on a 2023 Mercedes Sprinter 4500 Chassis

Updated 02/02/2026 | Published 01/21/2026

Products Featured in This Question

Redarc Tow-Pro Liberty Brake Controller w/ Universal Wiring Harness - Dash Knob - Proportional

(2710)

$217.00

Question:

I have a 2025 Thor Quantum class C motor-home on a 2023 Mercedes Sprinter 4500 chassis. On your website, it indicates that this wiring harness, 3063-P for the Tekonsha P-3 brake controller does not fit my 2023 Sprinter 4500 chassis. Can you confirm what will fit so that I can install that brake controller? I dont want to buy either until I am sure it will work. Thanks for your attention.

asked by: Jose S

Expert Reply:

Hey Jose. Does your 2025 Thor Quantum have the green connector underneath the driver's seat? If so the Tekonsha item # 3063-P brake controller adapter does fit. I attached a picture below so you can see what it looks like. This will allow you to plug the Prodigy P3 item # 90195 directly into it.

If you do not have the brake controller adapter, I recommend the Redarc Tow-Pro Liberty Brake Controller w/ Universal Wiring Harness item # RED52VR. This is a proportional brake controller that will engage your trailer's brakes when your Sprinter decelerates.

The Tow-Pro Liberty item # RED52VR has a unique installation method that allows you to mount the main control unit out of sight behind your dash. The only part visible is the control knob. This means no bulky controller to bang your knee on while driving.

What kind of trailer do you plan on pulling?

You can add this information, along with any other questions you have, where it says Add Comment.

expert reply by: Jerred H

3063-P
(click to enlarge)

Jose S.

1/22/2026

Thanks for the prompt response and advice, Jerrod. In answer to your question, we will be flat towing a Mini Cooper or a Ford Maverick. I will have to look under the seat when I actually get the motor-home. I know it has a trailer hitch but no brake controller and I was trying to get ahead of the game. You see, I just bought it and will be picking it up this weekend. ;-)

Jerred H.

1/22/2026

@JoseS You're welcome! You don't need a brake controller on a flat tow. Just a supplemental braking system installed on the tow vehicle. Something like the Curt RVi Series Shadow 2 Flat Tow Brake System item # RVI94FR for a permanent install or the Curt RVi Series 4 Portable Flat Tow Brake System item # RVI44FR for a portable system. They only require your motorhome to have a 7-way connector. Congrats on the new motorhome btw!

Jose S.

1/22/2026

Oh, boy. Sounds like the solution I need is going to be far more expensive than I expected. I thought a brake controller would be enough for the Mini Cooper. Right now, I have a U.S. Gear system installed in our Mini and have nothing in the Maverick. What little research I have done tells me U.S. Gear is no longer around or at least what I would need is no longer available? Ultimately, I'd like to tow either one depending on where I will be traveling. That argues for a portable system like the RVI44FR, right?

Jerred H.

1/26/2026

@JoseS Yes, you are correct. If you're going to be flat towing with multiple vehicles a portable system like the Curt RVi Series 4 item # RVI44FR is going to be the best option. It can easily be moved from your Mini to your Maverick, You will also have to purchase the Curt RVi Series Breakaway System item # RVI97FR. Each of your flat towed vehicle's will need to have a breakaway safety device installed and the Curt RVi Series 4 item # RVI44FR only includes one. The D- Cellorometer Unified brake systems by U.S. Gear have been gone for quite awhile. They relied on a specific control module inside your motorhome to operate.