Choose the variant
Use MS45.0 or MS45.1 for sensor and definition details. Common MS45 material remains here and in the two family guides below.
Image sizes and address ranges
MS4X lists a 1024 kB external-flash image. Its overview calls the parameter area approximately 128 kB, while giving 0x40000–0x5CF7F and a padded end of 0x5CFFF. The Definition Files page lists 116 kB partials. MS4X reference; MS4X reference.
Calculated inclusively, those ranges contain 118,656 bytes (115.875 KiB) and 118,784 bytes (116 KiB), respectively. They do not describe a complete 128 KiB slice. Keep the tool’s actual byte count, headers/padding and address origin in the file record; use the format expected by the selected definition and writer.
Integrity and authenticity
The source distinguishes a main CRC32, an additional monitoring checksum and RSA validation for OBD programming. Correcting a CRC alone does not supply a valid signature. MS4X reference.
For the selected software and write method, record how each required check is handled. Use current primary tool documentation for compatibility; the older overview’s list of products is historical context rather than a verified current support matrix.
Calibration guides
- Fuel mass and injector calibration — parameter roles, units and validation.
- Intake model, torque and DISA — related models and actuator-state checks.
- Shared calibration-file workflow — identification and provenance.
Keep software-specific addresses and conversions with their definition. Document an observed result with the exact MS45.0 or MS45.1 variant rather than assigning a universal value to MS45.
Sources and scope
Original reference notes by Tuning Wiki, informed by the linked MS4X Wiki pages. MS4X Wiki contributors and the authors credited by each linked project remain the source authors. Sources checked 10 November 2026. Suggested validation steps and worked arithmetic are editorial guidance; they are not a tested calibration or a claim of hardware verification.
- Siemens MS45 (revision 23142).
- Definition Files (revision 23632).