Wiring LED Tail Lights with Four Wires

Updated 07/02/2024 | Published 12/30/2020

Products Featured in This Question

16 Gauge, 4 Conductor Bonded Parallel Wire - Per Foot

(237)

$2.84

Fusion LED Combination Tail Light Bar for Trailers Over 80" Wide - Submersible - Red/Clear Lens

(160)

$29.06

Question:

Power up to lights good,plenty earth,im confused with the black wire,yellow wire and red.The 5 wires to trailer connected correctly,I dont know what Im doing or not doing thanks

asked by: Merv

Expert Reply:

If the wires from your trailer are good and the power is good, then we just need to figure out what each wire on the light itself does. The best way to do that is to take a 12 volt power supply and apply that to each of the wires on your lights to see which bulb it illuminates.
For example, when you use the Fusion LED Combination Tail Light Bar part # STL264RB, this has white, black, red, and yellow wires. The functions of these colors on this lights are as follows.
Black: Tail
White: Ground
Red: Step/Turn
Yellow: Backup

Double-check your own lights to see if they have the same functions then connect them to the matching wires from your trailer. I attached the install video of the tail light # STL264RB which can help guide you through the process.

expert reply by: Evangeline M