Usually, we can directly read data via OBD mode and program keys for CAN EIS after 2007, and our devices can identify EIS type automatically and calculate key pass.
For some old EIS(W215/W220/W230 etc.), devices cannot auto identify EIS and we cannot read EIS data on car. If we try to read EIS by IR reader on car, then the key pass may auto change, and even the original key won’t start the car.
If the original key is non-smart key, we can still program a key to customers; if it’s old-style smart key, it would be a huge trouble: very few OEM smart keys on market can be learned to the car, a specific key is hard to find out, and an OE order may cost 700-800USD.
Recently we’ve heard this issue, and solved in this way:
Read data out by programmers, ask professionls to edit the data file, and finally the key goes back to smart status.
In short, Do Not read EIS data by IR reader if our device cannot identify EIS type of old Benz.
Thanks to Aurora Smart.
Hope this could help!