But there was a catch: the interface cables. Early third-party cables used cheap FTDI or chipped serial-to-USB adapters with wildly inconsistent electronics. Ross-Tech’s official cables had a unique microcontroller that spoke a specific timing protocol. Unauthorized “dumb” cables would often fail or produce garbage data.
In the late 1990s and early 2000s, accessing a Volkswagen/Audi group car’s onboard diagnostics (OBD) required a dealer-level tool called VAG 1551/1552—a heavy, expensive brick of a machine. Then came a Swedish hacker and entrepreneur named , who created a software called VAG-COM (now VCDS). It allowed anyone with a laptop and the right cable to diagnose their car. vagcom_hwtype.exe
When you ran it, the program interrogated the connected VAG-COM cable and reported a hardware type —usually a number like 0xFA20 (Ross-Tech genuine), 0x9200 (Chinese clone with a PIC18F), or 0x0000 (dead/none). More interestingly, some cracked versions of VAG-COM would refuse to work unless this tool had previously “patched” the cable’s EEPROM to report a genuine hardware ID. But there was a catch: the interface cables