What are the Wire Functions for Optronics Transit LED Stop/Turn/Side Marker/Tail Light # STL90RB

Question:

Hello, which wire red or black is the brake wire and which one is the turn signal wire? I understand the white is ground.

asked by: Ming

Expert Reply:

On Optronics tail light # STL90RB, the red wire is for brake and turn signals and the black wire is for running lights. And like you said the white wire is the ground wire. Trailers have what is called a combined or 2-wire system. This means the brake lights and turn signals are on the same circuit on each side. I have linked a video review of this light for you.

expert reply by: Michael H