Autel IM508 program a spare key to Mercedes Benz SL 55 AMG R230 / W230 via OBD successfully.
It took a long time in order to get the password, but in the end, succeed.
I used the Get password function.
It took little bit longer than 30min and I had to switch the key between the EIS and the key reader many many times.
Car started straight away. Two keys are programmed.
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