I'm studying hard to understand how the ECU on my Audi A4 140hp works.
The control unit is an EDC16U31.
I'd like to start by removing the EGR.

The valve has already been removed, along with its radiator, and I've plugged the exhaust manifold and intake manifold.

Now the car has error P0405.

My question is:
Is it enough to delete the EGR and EGR hysteresis, or do I also need to disable some DTCs?

And if I have to clear the DTCs to disconnect the valve, can you explain how?

Thanks