I have a 2008 Duramax 2500HD outfitted with a factory ITBC.I pull a 398 Fuzion toy hauler with three axles. I purchased the RV in Fort Lauderdale in 2012 and pulled it back to East Texas. I took it on vacation to Colorado last summer with no problems with the braking system. After we had returned home from Colorado I hooked up to the RV to bring it in for a recall and noticed the DIC display was displaying unusual displays for the ITBC. The DIC would show the trailer connected part of the time and malfunction the next. When increasing or decreasing the voltage using the ITBC or - buttons, the DIC display would not show anything. When pulling the trailer down the road at 20 mph using the manual slide button function, the ITBC would slightly apply some braking to the trailer with no progressive braking display from the ITBC. You could not increase or decrease aggressiveness using the ITBC or - buttons.After reading some of your forum discussions I pulled both 7 pin trailer connectors 1.Bumper and 2.Bed of the truck out so I could inspect and test the continuity from the controller. The RV dealer installed the one in the bed and they spliced into the bumper connector wiring. I took time and removed all of their quick connectors and soldered all the connections, installed heat shrinks and put a good tape job on the entire splice. Hooked my trailer back to the truck and my problem disappeared. Must have been a loose connection or water problem. I could not see any signs of corrosion.The reason I added this comment was to let you know my factory ITBC is currently supporting three axles on my Fuzion. I had already made my mind up to by-pass the factory ITBC and install a P3 if I could not figure my problem out. This would be much cheaper than getting the Chevy dealer to work on the problem and charge an arm and leg, only to have the problem crop up again in a year.With my CanAm Commander 1000 side by side in the back I need all the braking I can get when coming off those Colorado mountain passes. Hope this comment was helpful.
comment by: O. T - 3/3/2013
Thank you for the information, it can be hard to come by on the ITBCs. Glad you were able to sort out the wiring gremlins, they can be quite a pain. Patrick B - 4/9/2013