If the dash shows the trailer connected message and when you manually slide the bar over and just the trailer brakes engage, that means it's working.. That's what I do each and every time I move the trailer as I'm driving out to make sure they are working.
If you are going less than say 20 mph and just hit the truck brakes, you will get little if any actual trailer brake engagement.. That's what makes the system so smooth.
Try getting up to 40 and above, then hit the brakes harder, and you will feel the trailer brakes working.
Are you going to be taking the trailer in to the dealer too? They won't be able to do much if you just bring in the truck.
After confirming they updated the computer with the IBC stuff, and maybe hook it up to a laptop and check that, not much else they are going to be able to do.
Have you read your owners manual on the operation of the IBC? It's spelled out pretty well how you determine your optimum gain settings and what to do to test it all out.
Good luck!
Mitch
