Can Separate Amber Turn Signals be Added to a Trailer

Question:

Good Morning - Have a brand new Featherlite trailer that have the brake/stop/turn run on the same wire. I added a side turn signal lamp for visibility, however it activates when the brake is depressed. Trying to remove the brake circuit out of that wire, but not sure it is possible without running a whole new wire from the tow vehicle which is a 2015 Ford F450. The light being added has a ground/clearance/turn function 7 Way round blade plug is in use. Thank you

asked by: Chris Y

Expert Reply:

Trailers in the United States have what is called a 2 wire system. One wire has the running lights (tail lights) for the whole trailer. The other circuit (one per side) is brake lights and turn signals.

All you need to do is separate out the brake signal from the turn signal using a special converter, # 118158. Please note this converter will only work with incandescent lights and not LED lights. If you need to have LED lights then the only other option like you said is to run wires independently from the truck to the new lights (provided that the truck also has turn signals by themselves and not combined with the brake lights). Based on what I can find on the 2015 Ford F-450 it has combined brake/turn signals so incandescent lights are the way to go.

The converter has a green wire for the combined right turn and brake light, a yellow wire for the combined left turn and brake light, and a white ground wire. The output side will have a green wire for light turn signal only, yellow for left turn signal only, and red for brake lights only.

The green and yellow wires will go to the new right and left turn signals and the red wire will go to the existing red brake/turn signal lights.

expert reply by: Michael H