Last night, on a roll i read the eeprom from the "new" unit and managed to get that to verify as identical a few times, so saved it. Just because!
Then I WROTE my HU firmware over it, read it back and verified what i'd written as being identical.
I put the new HU in the car and it was in GERMAN - It was late and i was hungry, so left it.
Just had a look and switched the menu language back to English and i was much happier. Still had CP....Got VCDS out to have a look and yep. CP still engaged.
HU was coded 000000 and i switched to 000002. The TV module had a fault code and i cleared that and sound came on!!!!
I cleared the CP fault on the head unit and it stayed gone.
I had to switch 08 in the HU adaption to 1 to get back the secret MMI menu back to get all the options i had enabled
SO RESULT!
YES.....reading your eeprom from your old HU and writing it to a different HU did work. It's an almighty faff dealing with small fiddly wires, reading/writing and so forth, but it IS possible!
I'm now going to switch back as my HU wasn't the problem this time and rebuild my glovebox
