My brake lights dont work check fuses and bulbs it happen after towing a trailer.everthing else is working fine even the cab brake ligth looking for any help:(

I have been having problems with the tail lights in my 2004 2500HD. The cab mounted 3rd light would work, but the two in the bed would not. Turned out to be in the junction block just in front of the rear bumper, where 4 harnesses are pluged in. When I would move the connector coming from the cab, the light would go on and off. Took a zip tie and pulled the connector toward the middle and it is working so far. In my case the terminal block is replaceable, which I might do yet. Part#15304995. Don't know if these would be the same, but maybe that helps.

thanks i have the same junction block and ill try playing with it any one else have anything

Any Body

Just to confirm- you did check the fuses located at the drivers end of the instrument panel and not just those under the hood? There is another set for the brake lights in that block. Circuits 6, 8 and 12 IIRC...