Where to Look for Brake Controller Harness on a 2003 Freightliner XC Chassis

Updated 10/10/2025 | Published 10/02/2025

Question:

I have a 2003 Tiffin Phaeton 35RH with freigtliner chassis XC I need to find out where are the prewires located for a trailer brake controller ???? Does this unit have them ? If so please tell me. I will be towing a 24foot enclosed trailer. I look all over under the dash but then again I dont know what im looking for. Thanks

asked by: Juan

Expert Reply:

Hey Juan, thanks for reaching out!

According to my research, the pigtail for a brake controller like the Tekonsha Prodigy P3 # 90195 will be located around the driver's side dash, but most likely found near the steering column. The harsh reality of brake controller wiring on motorhomes is that hardly any of the manufacturers actually tell people where that wiring harness is so I don' have an exact location for you.

Since you've already ruled out under the dash, the steering column is the next best place to look. What you'll be looking for is 4 blunt cut wires that should be bundled together. I don't know the color of the wires you're looking for, but the clues I referenced above should be enough to help you find it.

Once you do find it, would you be able to comment back on this page with what you found? This way others will be able to see when they're searching as well.

expert reply by: Jon G

Juan

10/5/2025

Somebody mention a 6 pin regtangular plug under the steering column. I found that one but wires are different color. Can you check about that ?

Jon G.

10/7/2025

@Juan I unfortunately don't have a wiring diagram for your motorhome, so you'll want to use a circuit tester like part # PTW2992 to test and see what functions those wires are connected to. I see you just picked up the Wiring Adapter # 3027-P. Does this look like what you found?

Juan

10/10/2025

@JonG I purchase that wire adapter to look under the rv for something similar to hook up to it. But unfortunaly there is none. We called freigthliner and the guy said that model 2003 Tiffin Phaeto 35 RH don't have the prewire. However I read somwere online that from 2000 and up it was installed on the freigthliner chassis XC. So ????? What is it. I'm in a pickle here. I'm a disable veteran moving to the east coast with a loaded 24' trailer (10400 lbs). If anyone have any ideas please post it here , Thanks.

Jon G.

10/10/2025

@Juan All of the info we get on motorhome brake controller wiring is hit and miss so I unfortunately don't have a pin-point location. If you aren't seeing a wiring plug that the Adapter # 3027-P fits, then you might need to be looking for a bundle of bare wires. What we know about motorhomes is that the brake controller wiring can be found under the driver's side dash, up around the steering column, or even under the front seat. You'll want to look all over for the brake controller wiring, and it might just be a bundle of wires as opposed to a plug.