✅ Free MS43 CheckFix Tool – Validate & Fix ECU Checksums

This free tool validates and corrects checksums on Siemens MS43 ECU binary files (5WK90012).
Works with 512KB .bin files read via OBD, Bootmode or Bench.
Ideal for tuners working with MS4X-series ECUs.

Features:

• Fast checksum validation
• Simple CLI usage
• Free forever

💡 No Python or installation needed – just download & run.