Troubleshooting Trailer Wiring of 2016 Chevy Colorado Not Functioning
Question:
I have 2016 Chevy Colorado LT 4WD 3.6 liter. The trailer plug on the truck is a 7 way and 4 flat. When I test the plug I have no power for the running lights. I do for the brakes and turn signals. I have checked the fuses and relays. When I disconnect the plug from the wiring harness and check the wiring plug I have power for running lights, brakes and turn signals. This checking without the trailer connected. Any ideas of what may be going on?
asked by: Kevin S
Expert Reply:
Hey Kevin, typically this issue is a dirty trailer wiring pin. I know you tried checking fuses and relays but you should also try sanding the pins of the 7-way to clean them off so that they can make better contact.

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Kevin S.
5/8/2024
After doing so, would it help if I applied some dielectric grease? Thank you.