Use VAGCOM_HWType.exe while the cable is plugged into both the USB port and the OBD2 port (or 12V supply) to verify the chip type.
If the interface is unresponsive, the microcontroller must be forced into Device Firmware Update (DFU) mode. This usually requires: Use VAGCOM_HWType
If you want, I can provide a concise parts list and step‑by‑step repair guide for a typical HEX‑V2 clone PCB failure (MCU/EEPROM/USB chip), or a side‑by‑side comparison table of specific clone models vs official units. Which would you like? Use VAGCOM_HWType