@ps603 If ITP is already off, you just need the CEM pin for vdash. The whole car configuration is stored in a small database in the CEM.
Configuration changes through VIDA are done with software downloads and are also stored on the Volvo servers. If you add a new module to the car, it's always 2 downloads. 1x software for the new module, 1x configuration change in the CEM.
If want to replace a defective module from the infotainment with a used one, you just have to disable ITP (infotainment theft protection) and can simply install a used one from a donor car.
If you want to upgrade your infotainment, like adding DAB, by using a used module, you have to add the wiring needed and need to know the correct software number for that CEM configuration change to download and install with VIDA. Or you can use third party tools like vdash, which can modify the CEM configuration way beyond the possibilities/limitations of VIDA, and without any software numbers, to enable that module.
I hope my explanation is understandable. English isn't my native language.
