For VW PQ platform I can say that units which are matched share the same key.
This shared key is stored in the eeprom of the unit but not in plain format but encrypted with a unique key for each unit.
So copying eeprom data (that area where the share key would be stored) will not work.
The handshake is initiated by the master (=cluster) and sends some encrypted data back and forth so both parties can verify if the use the same key.
I believe the VW MQB platform uses a similar (if not same) approach but there the gateway is the master.
(But I haven't studied this further though.)
Rgs H2Deetoo
H2Deetoo, did you make any more progress with this yet? On later PQ based cars such as Caddy and T6 Transporter the cluster is the master, the infotainment and distance control (radar) modules are the participants. I'm still wondering if the data can be manually copied from the original cluster and written to a replacement cluster and the CP scheme still work okay for the other modules.
