I rebuilt a trailer, first time towing it was with an 02 Ram and the brakes did not work (even with the override)
When I got my truck back, hooked it up and same thing.
I adjusted the brakes (brand new) until the wheel was tight and backed off one notch. Still no brakes even with override.
I checked voltage at the truck without the trailer plugged in and getting 9V once controller override is pressed, then the voltage drops to about 3v.
I have read that the voltage drops from the speed senors in the wheel not seeing the truck rolling, the brake controller works on a friend's trailer.
Any ideas? Only thing I can think is the truck has a bad ground to the harness.