Why Does a Marker or Clearance Light Only Have One Wire
Updated 05/09/2026 | Published 07/02/2018
Question:
I want to replace my marker, and running lights. The old ones have two green, and two white wires each. Any new ones I look at have only one black wire. What would I need to do, to replace the old lights?
asked by: Thomas
Expert Reply:
The marker and clearance lights you have now ground with a single wire hence why you have two wires total, one for power and one for ground. If the marker or clearance light only has one wire then this wire is for power and the light grounds though the mounting hardware. When you determine which of the two wires you have is for power, you just simply need to cap the other one off. If the new light with only one wire is installed in a rubber grommet then you will need to run a ground wire off of the mounting hardware.
I have attached our list of clearance and marker lights for you. Please let me know if you have any further questions.
Brian
3/31/2025
my rv camper has a marker light on the side and is a two wire system my new kenway lights only have one wire are do they have a built in ground
Jesse M.
3/31/2025
Lisa N.
5/8/2026
My old marker light has two black wires and the marking TBC. The new light has a red and a white. What do I do?
Robin H.
5/9/2026
Product Page this Question was Asked From
Thinline LED Trailer Clearance or Side Marker Light w/ Bracket - Submersible - 3 Diodes - Amber Lens
- Trailer Lights
- Clearance Lights
- Marker
- Rectangle
- Surface Mount
- Submersible Lights
- LED Light
- 4L x 1W Inch
- Amber
- Optronics
more information >
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Robert M.
7/1/2020
I have a 1981 1ton with the 5 cab marker lights on top I went to replace them and the old lights have 3 wires the new one only has 1 and it is set into a rubber mount what is the best way to hook them up?