Troubleshooting Trailer Brake Light Circuit Not Active on a 2001 Chevy Silverado 2500HD

Question:

I am trying to get the brake lights to work on my trailer all the other lights work fine just no brake lights what I have done so far is first of all hooked another truck up to the trailer and everything on the trailer works fine so I know the problem is in my truck I replaced the wiring conector on my truck its a seven prong conector by the way I have cleaned up the grounds and checked all the fuse boxes for blown fuses but still all I have is power to the signal lights but no power for brake lights and they run through the same prong on the conector Im out of ideas so any help you can give me would be greatly appreciated

asked by: Travis

Expert Reply:

Check the CHMSL fuse under the hood of your 2001 Chevy Silverado 2500HD. What you described is a very common problem that kills the trailer brake lights on your generation of truck.

You can easily tell if this fuse is blown by checking to see if the third brake light of the truck is activating properly when you step on the brakes. If it is not functioning then the problem is the CHMSL fuse.

expert reply by: Jameson C