Could Black Wire of Trailer Wiring be the Ground Wire
Updated 06/28/2018 | Published 06/27/2018 >
Question:
I have tail lights brake lights but no blinkers I know that the wiring is correct green to green yellow to yellow brown to Brown white is ground but on my utility trailer there is no white ground wire but there is one thick black wire is that the ground and is that why my blinkers are not working
asked by: Bob G
Expert Reply:
Most likely that black wire is the ground since it's the only circuit not accounted for and is thicker than the other wires. It's not uncommon for trailer wiring to not be the standard colors. I attached a trailer wiring diagram for you to check out as well.

Product Page this Question was Asked From
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Visible
- Tekonsha
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