2.Launch the Software Open the X-Prog3 PC Adapter software (version 10.40). Search for the Mercedes FBS4 VGS4-500-NAG2 gearbox by entering “vgs4” in the search box.
3.Check Wiring Diagram Check the Direct Connection Wiring Diagram in the software. Follow the on-screen instructions, then click “Confirm” to proceed.
Wiring Options: The diagram provides two modes: BENCH and BOOT. Use BENCH mode to read data from the original vehicle’s gearbox (TCU). For wiping and personalizing a second-hand external gearbox, connect both BENCH and BOOT modes simultaneously.
4.Connect to the Original Gearbox Securely connect the Launch X431 PC Adapter to the original Benz VGS4-500-NAG2 gearbox.
5.Read TCU Information After completing the connections, click “Read TCU Information” to retrieve data from the original gearbox.
6.Extract EEPROM Data Click “Read EEPROM Data (BENCH)” to extract the EEPROM data. If BENCH mode fails, switch to BOOT mode and retry.
7.Erase the External Gearbox After retrieving the original vehicle’s ECU data, connect the X431 X-Prog3 PC Adapter to the external (second-hand) gearbox. Ensure both BENCH and BOOT modes are active, then click “Erase” to clear the external ECU’s data.
8.Personalize the New Gearbox Click “Personalization,” select the original vehicle’s EEPROM data to write into the external ECU, and confirm with “OK” once complete.
9.Verify and reinstall Click “Read TCU Information” again to verify that the external ECU data has been erased and updated successfully.
Reinstall the gearbox into the vehicle. Complete any necessary programming and coding to finalize the setup.