Wire Color Codes for Optronics 3 Wire Taillight Wiring Pigtail

Updated 05/21/2025 | Published 03/09/2016

Products Featured in This Question

LED Backup Light for Trucks or Trailers - Submersible - 36 Diodes - Round - Clear Lens

(282)

$46.10

2-Wire Pigtail for Optronics Backup and Utility Trailer Lights - 2-Prong PL-3 Plug

(121)

$4.82

Question:

Hooking up and 4 inch round LED light the red and the black I have figured out is the white a ground

asked by: Bill

Expert Reply:

On a three wire pigtail that's being used on a stop/turn/taillight, the red wire carries the brake/turn signal circuit, the black wire carries the running lamp circuit and the white wire provides the ground connection.

The # BUL53CB lamp you mentioned is a single function lamp only, for that particular lamp, you'd use a 2 wire pigtail, like part # A45CB. On the 2 wire pigtail, red carries the power to the lamp, the white wire is the ground connection.

expert reply by: Mike L

Jim L.

5/18/2025

Wow, I'm glad I finally found the information that should be included with every light you sell. I am considering buying the Optronics OPT95KB. Am I to assume that the 4th (yellow) wire is the reverse lights? Jim

Andrew N.

5/21/2025

@JimL yes, yellow is the reverse signal for the Optronics Smoke Lens ID Light Bar - Turn, Brake, Tail, and Backup Light - Red/White - 15" # OPT95KB (STL871DSRSHB)