Tail light hyperplasia and fault code

[RDretired]

I have a 2020 3500 HD. Itokk the factory box off and installed a deck on the truck with LED tail lights. I am getting a hyper flash and a fault code on the dash. I have tried installing 3,6,12,24,ohm resistors in parallel with the signal light circuit. I have tried 6 ohm resistor in both the tail and signal circuits. I have even tried conventional light bulbs.  Techbulletins just say I need more than 55ma of current. Obviously that is not the case. It is looking for something very specific. Has any got a fix for this

[RDretired]

So I talked to a fella that says these new trucks are wired with a Euro style taillight system. That is why we have 4 wires to the tail light instead of the old 3 . They use a bulb for signal and a separate bulb for brake light. Black is gnd. Brown tail. Green signal. I just need to figure out the Color of the other wire for brake light .