How to Identify the Wire Functions of Trailer Wiring on a 2002 GMC Sierra
Question:
2002 GMC 2500 HD left side box cable has 8 wires the question is light blue or dark blue the wire I need and what happens with the extra wire does it piggy back onto another pin. The one wire that is longer is dirty, it is actually light blue
asked by: Dave S
Expert Reply:
I can help you determine the functions of the wires in the bundle you sent in a picture of by testing them with a circuit tester like part # PTW2993 but we don't have a way to identify them just based on color.
So have a buddy apply the various taillight functions of your truck while you probe all of the wire cores with the tester and you'll be able to know for sure the functions.
Product Page this Question was Asked From
7- and 4-Pole Trailer Connector Socket w/ Mounting Bracket - Vehicle End
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- No Tow Package
- 7 Round - Blade
- 4 Flat
- Plug Only
- Hopkins
more information >
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Dave S.
3/18/2020
8 wires in the harness 7 pin connector I need to find the answer for the 8th wire