Trailer Brake Controller for 2009 Mercedes-Benz ML350 with Factory Tow Package

Question

Question:

Im looking for a trailer brake controller for a 2009 Mercedes-Benz ML350 with a factory tow package. I see the only brake controller you list for this car is a Redarc Tow Pro Liberty that has to be installed into the dash. I am wondering why this is the only one you list. Info I found online shows you previously recommended the Tekonsha Prodigy P2. This would be easier to install. Is there some reason it wouldnt work in this car?

asked by: Dana L

0

Expert Reply:

Hey Dana!

I found the Q&A page you were looking at and it's just an older page with outdated information. The Tekonsha Prodigy P2 has been discontinued, since Tekonsha's parent company filed for bankruptcy at the beginning of the year. I did read a recent article that the company has been purchased, but i do not know if the Prodigy will be back in production or if we will carry when it is.

With that being said, the Redarc Tow-Pro Liberty Brake Controller # RED52VR would be my choice in trailer brake controllers for your 2009 Mercedes-Benz ML350, even if we did still have the Prodigy. My favorite part is the behind-the-dash installation that gives it more of a factory look. The Prodigy was what we call a "knee-knocker," meaning the installation location was in a spot that would commonly hit your knee when entering the vehicle. The differences beyond that are minimal. Both controllers are proportional brake controllers, both are compatible with electric and electric-over-hydraulic trailer brakes, and both are going to have adjustable and manual brake output options.

The only place that the Prodigy had the Tow-Pro Liberty beat is that it was compatible with up to 4 axles, but if you have more than 2 axles on the trailer that you'll be controlling then you can go with the Redarc Tow-Pro Elite Brake Controller # RED44FR for 3 axles or the Redarc Tow-Pro Link Bluetooth Brake Controller # RED57AR for 4 axles.

In all, the Redarc brake controllers are great options and I'm confident that they'll be very solid for you. What kind of trailer are you planning to tow with your ML350 and how many axles does the trailer have?

expert reply by: Jerry B

0

proportional brake controller time to reach max brake power
(click to enlarge)

Dana L.

10/29/2026

Jerry, thanks for your reply. I didn't know about Tekonsha's troubles, but I see now that the Prodigy P3, which replaced the P2, doesn't appear to be available right now. So it looks like the Redarc Tow Pro unit is my best option now--if I can find a place to put the dash knob. I have a 2-axle flatbed trailer with electric brakes, so the basic unit should be adequate.

Jerry B.

10/29/2026

@DanaL I'm happy to help! Yes, currently you are limited to what's available. With that being said, they are commonly resold online so that's an option for you. My favorite accessory to the # RED52VR is the Universal Mounting Panel # 331-TPSI-001, which will give the Tow-Pro Liberty even more of a factory look. It goes into one of the open slots on the knockout panels to the left of your steering column and just blends in from there. You can see photos of this on the product page and see if that's a good match for you!

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Trailer Brake Controller for 2009 Mercedes-Benz ML350 with Factory Tow Package

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