e61 cas2 old key

tried autohex first, wouldnt program key...

read cas2 using hexprog
made key using other tool
wrote back file using hexprog

now cas works, sees key but no start. ISN sync issue
tried sync, says comms error between CAS and DDE

tried orignal cas2 eeprom but made no difference

Any idea?

..was it a lost key situation or the key programming was due to the fault comms error between ECU and CAS ?

e61 cas2 old key

tried autohex first, wouldnt program key...

read cas2 using hexprog
made key using other tool
wrote back file using hexprog

now cas works, sees key but no start. ISN sync issue
tried sync, says comms error between CAS and DDE

tried orignal cas2 eeprom but made no difference

Any idea?

what error you got on autohex for programming key, you can program key for this car from key learning option 2 OBD itself.
As you have already programmed key for the error you are getting you can read ISN from DME and write to CAS using autohex. it will ask for sync at the end also.

Close car using key in driver door lock
Leave it for 20 min
Unlock the car
Sync DME-CAS