What Is The Purpose Of Having A Second Ground For Trailer Lights
Updated 12/22/2025 | Published 10/23/2024
Question:
Im preparing to rewire a 97 Shorelander saltwater trailer. There are two white ground wires proximate to each tail light attached to the frame. One is for the tail light and the other runs through the frame to locations unknown. The 4 wire flat plug in has white ground attached at the trailer tongue. Can you help me understand the purpose of this second ground wire that terminates at the tail lights on both sides and where it might be connected on the other end? Thanks in advance
asked by: Rodney S
Expert Reply:
Hello Rodney, thanks for reaching out. Having a second ground is fairly common for trailers. Each light will be grounded and then later grounded to the frame. I am not sure where exactly on the frame of your trailer this would be grounded, the best way to find it is to trace the wires. The second ground is not a requirement, but most people do this just to be thorough or as a safety measure. Just make sure you are grounding to good clean metal free of any rust or corrosion.
Product Page this Question was Asked From
Optronics LED Combination Trailer Tail Lights - Submersible - 40 Diodes - Driver and Passenger Side
- Trailer Lights
- Tail Lights
- License Plate
- Rear Clearance
- Rear Reflector
- Side Marker
- Side Reflector
- Stop
- Tail
- Turn
- Rectangle
- Surface Mount
- Submersible Lights
- LED Light
- 8L x 3W Inch
- Red
- Optronics
more information >
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Jesse M.
12/22/2025
Hey Rodney, did tracing those white ground wires on your Shorelander trailer help you figure out where the second one connects? Knowing how that turned out could really help others working on similar rewiring projects.