Factory trailer brake control issue

[Paul]

The facts. 2008 Chevy 3500/cc/drw/lmm duramax/allison/4wd. 78000 miles. Bone stock.
Factory trailer brake control (itbc) which has worked great til now.
The dic flashed "service trailer brake system" on the way home from Harlan in July and i had no trailer brakes at that point. All lights where working.Pulled over and checked all fuses,they were good. Cranked her back up and had no more problems til now
The "service trailer brake system" comes on every time i drive it now even without being hooked to one.
I have eliminated the following causes,
Trailer,7pin connector,ALL connections,fuses,ABS system and driver stupidity.
No trailer brakes = bad news @25k towing.
Google search of this deal makes me think i know what the problem is.
If you have any experience with this problem,please chime in!
TIA,Paul...

 

[mcutler]

Mine does it in a hard rain, only after I put another plug in bed, have since cut that plug loose, now all does it if water in bed and rolls out of tailgate. Sometimes if I hold the brakes to long; at a light or heavy traffic, it will blow a j-case fuse (30 amp). Took me a while to find it, is not labeled as anything to do with the trailer brakes, I carry many spares. No solution for ya Paul, just similar experience.