How to Determine the Wire Functions of LED Car Trailer Lights

Expert Reply:

Without knowing the specific lights you have, I do not want to speculate. Instead, if you look at the backs of the lights where the wires enter the housing, it may say what the function of each wire is.

On the lights that we sell white is usually ground, yellow is left turn signal and brake lights. Red can sometimes be a brake light only on lights so-equipped, or it could be running lights, and sometimes it is turn signal and brake lights. Brown is almost always running lights.