Quality validation end to end: audit, samples, PPAP and production monitoring
Quality is not a final inspection. It is four deliverable gates: system audit, sample validation, PPAP submission, production monitoring.
7 min read · 2026-08
Gate 1 — supplier system and process audit
Before nomination we audit on site, scoring IATF 16949 system elements and VDA 6.3 process elements, with ESG and environmental compliance added where the client requires it. Output is a score sheet, a non-conformity list and a corrective action plan; sampling starts only after closure.
- ▪System documentation and certificate validity check
- ▪VDA 6.3 P2–P7 process scoring
- ▪On-site capacity and equipment verification
- ▪ESG: working hours, environmental permits, hazardous material handling
Gate 2 — sample and first-article validation
Sampling confirms three kinds of conformity: dimensional, material and functional. Dimensions come as a full report including CMM data, material as a mill certificate plus RoHS/REACH declarations, function as a report against the agreed test spec. Problems found here are the cheapest to fix.
Gate 3 — PPAP submission
The submission level follows customer requirements, usually Level 2 or Level 3. A full package covers PSW, control plan, process flow, PFMEA, MSA, initial process capability, dimensional and material reports, appearance approval and packaging specification. We pre-review internally so the package is not bounced back repeatedly.
- ▪Part Submission Warrant (PSW)
- ▪Control plan and process flow diagram
- ▪PFMEA and MSA (GR&R)
- ▪Initial process capability study (Ppk / Cpk ≥ 1.33)
- ▪Dimensional report, material report, appearance approval
Gate 4 — production monitoring and issue handling
In series production we run pre-shipment inspection per batch (typically AQL level II, 2.5–4.0) and issue a monthly quality trend. Deviations follow 8D: containment within 24 hours, preliminary root cause within 48 hours, closure within 10 working days, with all records kept against the batch.
Engineering changes and re-validation
Changes to material, tooling, line or sub-supplier all require a change request, and the change level decides whether PPAP must be resubmitted. Unreported changes are the single most common source of production-phase quality incidents, so this is a hard clause in our supplier agreements.
Quality FAQ
- Is a full PPAP always required?
- It depends on part classification and customer requirements. Safety-related or OEM-delivered parts should be Level 3; internal pilot parts or low-risk consumables can drop to Level 1–2, but the control plan and dimensional report should stay.
- Can we commission pre-shipment inspection only?
- Yes. PSI can be ordered standalone, sampled to AQL, with a photo-documented report usually completed 1–2 days before container loading.
- Can our own team join the audit?
- Yes — remotely by video or on site with us. The audit checklist is shared beforehand and the report follows your template.