What Does Some Trailer Wiring Have 2 Brown Tail Light Wires
Updated 04/05/2018 | Published 04/04/2018 >
Products Featured in This Question
Question:
there is a 5th wire coming from the trailer that is brown and yellow
asked by: Don
Expert Reply:
Common 4-pole trailer wiring like # HM38138 uses one wire, the brown one, for the running lights on both sides of the trailer.
Sometimes what is called a 'wishbone' harness is installed on the trailer and this simply uses two separate running light wires - brown with yellow for left and brown with green for right - to make it easier to connect to the trailer lights since that way no jumper wire will be needed to cross from one side to the other.
Some examples of wishbone style 4-pole trailer wiring are parts # A40W42B, # A10-4225VP and # A40W5B. The linked photo shows you a 5-pole set-up that also has the same dual-brown-wires for the tail lights.
The linked article that covers all popular types of trailer wiring will help clarify how the functions are assigned to each wire on a connector.
Featured Help Information
Miscellaneous Media
Continue Researching
- Search Results: wiring harness
- Shop: Trailer Wiring
- Shop: 25 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire
- Shop: 40 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire
- Shop: Peterson LED Trailer Tail Light - Stop, Tail, Turn - 12 Diodes - Red Lens - Qty 1
- Search Results: trailer lights
- Search Results: submersible led trailer lights
- Shop: Peterson Clearance and Side Marker Trailer Light Kit - Submersible - Incandescent - Red Lens
- Shop: Thinline LED Trailer Clearance or Side Marker Light w/ Bracket - Submersible - 3 Diodes - Red Lens
- Shop: GloLight Thinline LED Trailer Clearance or Side Marker Light - Submersible - Rectangle - Red Lens
- Shop: Blue Ox Towed Vehicle Battery Charge Line Wiring Harness
- Article: Trailer Wiring Diagrams
- Video: Demco SBS Towed Vehicle Battery Charge Wire Kit Installation - 2019 Jeep Wrangler Unlimited
- Video: Demco SBS Towed Vehicle Battery Charge Wire Kit Installation - 2023 Jeep Wrangler Unlimited
- Video: Review of Blue Ox Towed Vehicle Battery Charge Line Wiring Harness - BLU44ER
- Q&A: Why Does Trailer's Wiring have Two Brown Wires
- Shop: Trailer Hitch
- Search Results: trailer hitch
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Search Results: trailer wiring
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: trailer tires and wheels
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Shop: Suspension Enhancement
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Video: Measuring To Choose The Right Trailer Axle
- Article: How to Measure Your Trailer Wheel Bolt Pattern
- Q&A: Installation Time for Blue Ox BX1128 Flat Tow Base Plate Kit for 2016 Jeep Grand Cherokee
- Shop: Brake Controller

