Describe the failure precisely
Record whether a person cannot read the text, a scanner cannot decode a symbol or a business system rejects decoded data. These are different problems. Capture the part identity, material, finish and stage of processing. Compare the failed item with the approved sample under the same conditions where possible.
Check the complete path
For text, review content, location and viewing access. For a code, compare the actual data and required symbol format with the approved release. Identify changes in lighting, orientation, cleaning or assembly since the original approval. Do not assume that applying a darker mark will solve a data-format or installed-access problem.
Authorize a defined correction
Keep affected parts segregated while the cause is reviewed. Re-engraving, overmarking or removing a mark may change the surface or create conflicting information. Obtain the appropriate disposition before proceeding. Record which parts were reworked and what was inspected afterward. Use the findings to update the drawing, setup or data process rather than treating each failure as an isolated cosmetic issue.