How to program new keys to Mercedes C Class W204 with CGDI prog MB

CGDI Prog MB key programmer is a popular tool for Mercedes owners.

Here are the guides and tips to add new keys to Mercedes C Class W204 with CGDI prog MB.


Step 1: Connect CGDI prog MB to computer

Step 2: Calculate password

Step 3: Save EIS Data

Step 4: Generate Key File

Step 5: Read/write the key


Step 1: Connect CGDI prog MB to computer

Step 2: Calculate password 

Open CGMB software

Go to EIS> Read EIS Data to current key status


Click on Computer Password> Copy key without key > Collect Data

Select OBD mode and press OK


Wiring diagram display


It prompts “Please unplug the direction lock (ELV), and connect the clip on the yellow line of the OBD line to the K-line on the directional lock plug. (The most fine line in the directional lock connector is the K-line)”.

Then click OK


Insert the simulation key into the EIS in 30 seconds…

Start keyless collection…


Save the file

cgdi-mb-class-204-all-keys-lost-6 cgdi-mb-class-204-all-keys-lost-7

Step 3: Save EIS Data

Select Computer Password> Copy key without key> Upload data

Select the file just saved

PASSWORD computing success


Click on Query result

Copy the key password

Go to EIS> Paste the password> Save EIS Data


Save the file successfully



Step 4: Generate Key File

Select Generate Key File> Load EIS File


Open the EIS data files saved

Then click on Generate Key File

The key file was generated successfully



Step 5: Read/write the key

Select Read/write Key> Read key/Chip

Read success


Note: Smart key please choose 41 format, common key and BE key please choose 51 format!

When wiring the original key, please make sure that it is wiped by the CGMB, otherwise the write will fail!

Then click OK


Open the file to write data


CGDI MB writes Class w204 success


Click on Read Key/Chip again


New key was programmed successfully.