The actuator kicking on and then off when you plug it into your 2018 Ram 4500, sounds like it is the system being primed.
As far as your truck not recognizing the trailer goes, the truck needs to see resistance of the trailer's brakes to recognize a trailer is connected, if it doesn't see this, it won't activate the brake controller.
Additionally, I recommend checking your trailer plug connection and your ground connections ensure they are clean, and free of debris and dirt. view full answer...
Go To Results