Utility Trailer Light Wiring Diagram and Required Parts
Question:
Looking for a wiring diagram and all parts needed to install new lights and wiring on my old utility trailer - 12ft deck, no brakes.
asked by: Ed
Expert Reply:
I have attached two basic trailer light wiring diagrams of utility trailers for you to check out. The difference between the two diagrams is the type of wiring harness that is being used. Diagram 1 shows a traditional wiring layout with jumper wires to provide running light functions for both sides of the trailer and Diagram 2 shows a wishbone harness. The wishbone harness has two running light wires, one for each side of the trailer. Diagram 2 is the preferred method and it is more common on newer trailers and new tail light kits.
The Optronics Trailer Tail Light Kit, # TL29BK, uses a 25ft wishbone style harness, which is more than enough wire for your trailer. This kit also comes with two clearance lights, two tail lights, and a license plate bracket.
If you would prefer LED lights, check out the Trailer Tail Light Kit, # TL16RK. This kit also includes all parts needed to complete the installation and the wishbone harness.
The typical parts breakdown for a utility trailer is as follows
Right hand tail light ( # ST8RB or # STL8RB for LED)
Left hand tail light ( # ST9RB or # STL9RB for LED)
Two clearance lights ( # MC32AB or # MCL32AB for LED)
4-way flat wiring harness ( # W002230)
Deluxe Wiring Installation Kit - Includes all necessary hardware ( # HM51020)
I have attached a link to our trailer lights page for you to check out. I have also attached installation videos that show how to install tail light wiring and a tail light kit on a utility trailer.

Products Referenced in This Question
Hopkins Deluxe Trailer Wiring Installation Kit
- Wiring
- Tools for Wiring
- Wiring Kits
- Installation Kit
- Hopkins
more information >
LED Trailer Clearance or Side Marker Light w/ Reflex Reflector- 3 Diodes - White Base - Amber Lens
- Trailer Lights
- Clearance Lights
- Rear Clearance
- Side Marker
- Rectangle
- Surface Mount
- Non-Submersible Lights
- LED Light
- 4L x 2W Inch
- Amber
- Optronics
more information >
Optronics Combination Trailer Tail Light - 6 Function - Incandescent - Red Lens - Passenger Side
- Trailer Lights
- Tail Lights
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Square
- Surface Mount
- Non-Submersible Lights
- Incandescent Light
- 5-5/16L x 4-9/16W Inch
- Red
- Optronics
more information >
Combination Trailer Tail Light - 7 Function - Incandescent - Square - Red Lens - Driver Side
- Trailer Lights
- Tail Lights
- License Plate
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Square
- Surface Mount
- Non-Submersible Lights
- Incandescent Light
- 5-3/16L x 4-9/16W Inch
- Red
- Optronics
more information >
Combination LED Trailer Tail Light - Submersible - 6 Function - 11 Diodes - Passenger Side
- Trailer Lights
- Tail Lights
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Square
- Surface Mount
- Submersible Lights
- LED Light
- 5L x 5W Inch
- Red
- Optronics
more information >
Combination LED Trailer Tail Light - Submersible - 7 Function - 14 Diodes - Driver Side
- Trailer Lights
- Tail Lights
- License Plate
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Square
- Surface Mount
- Submersible Lights
- LED Light
- 5L x 5W Inch
- Red
- Optronics
more information >
Optronics Trailer Light Kit for Trailers over 80" Wide - Submersible - 25' Wiring Harness
- Trailer Lights
- Tail Lights
- License Plate
- Rear Clearance
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Rectangle
- Kit
- Surface Mount
- Submersible Lights
- Incandescent Light
- 8L x 3W Inch
- Red and Amber
- Optronics
more information >
4-Flat Connector Wishbone Style - Trailer End
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 21 - 30 Feet Long
- Plug and Lead
- 4 Flat
- Wesbar
more information >
Product Page this Question was Asked From
Standard Trailer Light Kit with 25' Wire Harness
- Trailer Lights
- Tail Lights
- License Plate
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Square
- Kit
- Surface Mount
- Non-Submersible Lights
- Incandescent Light
- 5L x 4-1/2W Inch
- Red and Amber
- Optronics
more information >
Featured Help Information
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