When no original unit is available, or completely damaged and not possible to read, you would need to do the following:

1. Connect to the vehicle via OBDII

2. Open the Mercedes FBS4 software and select Electronic Ignition Switch (EIS) press “Info”

3. Press “Save” to save personalization data file (EIS4 data file) to a location on your PC

4. Now set up the donor unit on bench, using CB403 Cable and ZN151 (for reference section 5.3)

5. Open the Mercedes FBS4 software and select TCU option

6. Press “Info” button to establish connection

7. Set the unit to “Virgin” state trough the dedicated button.

8. IMPORTANT : At this stage you need to set the VIN of the vehicle to the donor TCU module

9. Once the VIN is set proceed to next step.

10. Press “Personalize” and select the file with the saved EIS4 data from the EIS

Once complete, software would ask you to turn IGN OFF and ON to finalize the procedure

N.B. Unit activation happens automatically after 100 ignition cycles.