How muki01/vag_kw1281 works
VAG KW1281 is Arduino/ESP32 firmware for communicating with Volkswagen Group ECUs over a K-Line interface. The principal workflow is to connect to a control unit, read identification and diagnostic data, decode measuring groups, and display results over serial; the firmware also supports scanning, fault clearing, sniffing, and ECU simulation. The README documents the product modes and protocol behavior; sampled source excerpts are data and command definitions, not the main runtime flow, so implementation-level links are limited.
Main entry points: VAG_KW1281 Main firmware · Basic_Communication_Test.ino Communication example · Basic_KW1281_Simulator.ino Standalone simulator · Codes.h Command and response codes
Components 16
Diagnostic operation
- Main firmware
VAG_KW1281 - Tester mode
VAG_KW1281 - Group decoding
VAG_KW1281 - Fault handling
VAG_KW1281 - Group scan
VAG_KW1281 - Sniffer mode
VAG_KW1281 - ECU simulator
VAG_KW1281
KW1281 protocol
- Command and response codes
VAG_KW1281/Codes.h
Example firmware
- Communication example
Basic_Communication_Test/Basic_Communication_Test.ino - Standalone simulator
Basic_KW1281_Simulator/Basic_KW1281_Simulator.ino - Recorded ECU responses
Basic_KW1281_Simulator/Codes.h
Vehicle interface
- VAG control unit
- K-Line interface
- Arduino or ESP32
Other components
- Operator
- Serial monitor
Connections 17
- Operator → Main firmware: selects mode
README.md - Main firmware → Tester mode: runs mode
README.md - Main firmware → Sniffer mode: runs mode
README.md - Main firmware → ECU simulator: runs mode
README.md - Tester mode → VAG control unit: exchanges K-Line data
README.md - Tester mode → Group decoding: decodes groups
README.md - Tester mode → Fault handling: reads or clears
README.md - Tester mode → Group scan: scans groups
README.md - Main firmware → Command and response codes: uses protocol codes
- ECU simulator → VAG control unit: emulates ECU
README.md - Standalone simulator → Recorded ECU responses: uses response data
- Communication example → VAG control unit: connects to
README.md - Arduino or ESP32 → K-Line interface: UART connection
README.md - K-Line interface → VAG control unit: level shifts
README.md - Arduino or ESP32 → Serial monitor: prints diagnostic output
README.md - Sniffer mode → Serial monitor: prints raw traffic
README.md - Group decoding → Serial monitor: prints decoded values
README.md