How To Install a Brake Controller on 2017 Mercedes-Benz Sprinter 3500

Published 11/20/2019

Products Featured in This Question

Hook Probe Circuit Tester

(58)

$12.05

Tekonsha Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In

(115)

$30.23

Roadmaster Stop Light Switch Kit

(580)

$46.47

Question:

trying ti install a brake control on a 2017 Mercedes Sprinter chassis 3500 sun-seeker , the coach has 7 way on the tail-end , and under the drivers seat i located 3 plugs 1st one is white has 4 poles in it and has 3 hot , 2nd one was gray just has 3 poles none hot , 3rd one has 2 poles non hot . if t is not equipped with a plug in style can I hard wire , i have heard of people having problems with that system on a hard wire job .

asked by: Guy S

Expert Reply:

You can hard-wire in a brake controller, and it seems that there are not a lot of the Sprinter 3500 models that are pre-wired, at least from what I've seen in my research. I have not seen any reports that this isn't possible, and we even have an installation video to walk you through the process.

The way to find out whether or not the plug is present by using a circuit tester like the # PTW2993 and testing for a hot wire when the brake is pressed- it's possible that one of the plugs that you've already tested and was not hot, is in fact hot when the brake is pressed. If you're able to find that plug, you can use the Tekonsha Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In # 3063-P (this is not a universal plug, but if you let me know what model brake controller, you're installing I can let you know if it works).

If you don't have a hot wire when the brake pedal is pressed, you'll need to hard-wire in your connection to the brake controller. You will need to wire in a separate brake signal switch wire with the Roadmaster Stop Light Switch Kit # RM-751475, as well as making connections to the 12v power, brake controller wire and ground connection. I've attached a detailed video on how to hard-wire in a brake controller on the 2017 Mercedes-Benz Sprinter 3500 that shows how to complete all of these tasks and get a fully working brake controller in your vehicle.

expert reply by: Erik B