My trailer lights are not working

[ueww40]

On my 2004 Tahoe with 5.3 ltr engine I have NO power on the brown wire of the trailer connector underneath the rear bumper of the Tahoe. Blinkers and brake lights work fine on the trailer but no running tail lights. Everything works fine on the Tahoe. I doubt that it is a wiring problem but rather a fuse problem, but I don't know what fuse I should check. Anybody have any suggestions what this could be? Thanks!

 

[ueww40]

I checked the ground pin on the connector and it is good, but I have no power on the brown wire. I do have power on the yellow and green wires on the connector. I assume that the tow package connector with its wire harness is on its own circuit and I also assume that it has one or more fuses. It would help tremendously if someone could tell me what fuses serve the tow package harness (if any) and also have a diagram, so I can troubleshoot/trace each wire from connector to where ever its ends