What a checksum check can establish
Control-unit software can include values used to check the integrity of defined data regions. Modifying covered content may require the relevant integrity values to be handled correctly. Which regions and algorithms apply depends on the platform and file. A generic “checksum corrected” label should not replace a record of the tool and operation that produced it.
Why the original may be required
Some checksum workflows rely on a genuine unmodified original as their project basis. EVC documents this requirement for specific WinOLS modules, including Bosch MED17/EDC17 support. Preserve the real original and keep it connected to the edited version. A previously modified file renamed “original” does not establish an appropriate baseline.
Assign responsibility before editing
Decide which documented tool operation will verify and, when appropriate, correct the integrity information. Follow the exact module or programming-protocol instructions. Avoid assuming that every editor, automated calibration tool and flasher performs the same correction. The Stage1Files public material does not establish a universal automatic checksum-correction guarantee. Confirm the requirement for your workflow.
Separate integrity from compatibility
A file can pass an integrity check and still be the wrong software for the control unit. Conversely, an error may relate to a file format, incomplete data or an incorrect original basis rather than a calibration target. Resolve the cause using the appropriate tool documentation and technical support. Do not suppress a warning merely because the file size looks plausible.
Keep an auditable result
Record the original and output names, software identity, tool and module versions, the reported result and the intended programming protocol. A SHA-256 hash is useful for identifying a particular stored file; it is different from the controller-specific checksums inside that file. After programming, verify the vehicle using the checks appropriate to the job.
Further reading
Check ECU & TCU coverage or contact Support about a specific file.