Troubleshooting Trailer Brake Light Circuit of 2003 GMC Sierra Not Functioning
Question:
My dad has been trying to fix his trailer light issue for a couple weeks now on his 2003 gmc Sierra 2500. He has replaced fuses, brake switch, relays, alternator, signal switch, trailer plug, brake box. Just about everything you can. Has power at the trailer plug but when hooked to a trailer has no brake lights. Tried it hooked to 2 trailers same outcome. Hooked another truck to the trailers and everything works as it should.
asked by: Zac
0
Expert Reply:
Have him check the third brake light fuse in your Sierra. Most of the time this problem is that.
expert reply by:
Jameson C
0
Product Page this Question was Asked From
Adapter 7-Pole to 4-Pole and 5-Pole
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 7 Round - Blade
- Plug Only
- 4 Flat
- 5 Flat
- Hopkins
more information >
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