Aftermarket brake controller

[Jebarkas]

Tried to find an answer to this but could not find one using search bar. I have an aftermarket reese brakemann t209 which i took from my 2004 ram. It works fine. Truck is 2019 classic 5.7 slt. Controller is a 2014 model. What is the issue if I do not flash the computer? Does the unit work? If the only issue is that I can't see the unit in the screen I am fine with that. If i am breaking a rule posting this here please forgive this new to forum user.

Did anyone answer your question? I also have an aftermarket controller and want to know f I need to get it “flashed”