Oddly enough I've been messing about with this system for the last couple of weeks on a rig I've lashed up.
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As i understand it, I think there are (at least) two approaches depending on whether you have the 5 digit pin code.
If you have the code (which i dont) there is a process to add new, pre-coded transponder keys which can be initiated using software like AlfaOBD via a properly wired OBD connector which talks to the immobiliser box and triggers the key learn process.
If you don't have the code you may be able to reverse-engineer it by dumping data from an eeprom in the immobiliser box.
In theory this data can also be used to pre-code a blank immo chip to work directly without having to be "added" as a new key.
I'm working through this process and have dumped the immobiliser eeprom from my rig but the software that is supposed to tell me the code is not giving a valid code. As this part of the process isn't giving me the right answer I haven't tried to "burn" a new chip from this hex dump but I guess I will need to try it to be sure.
Most pictures I have seen of the "code2" box show a green label but my test rig one has a white label.
Did the people you spoke to give specifics about why 2000 registration is difficult ?
Hopefully it isn't something to do with the white label immo box but I've ordered a green label box off eBay to see if I get different results.
If anyone knows more about this I would be interested to hear it.
As per usual, the wiring diagram in eLearn has an error in it.
Cheers,
Graham