Each year, the International Automotive Oversight Bureau (IAOB) analyzes audit data to identify the most common major nonconformities raised during IATF 16949 audits. These recurring findings provide valuable insight into the areas where organizations most often face challenges—and where focused improvements can make the greatest difference.
To help organizations better understand these findings, the IAOB has developed resources covering the Top 5 Major IATF 16949 Nonconformities. These materials are designed to promote consistent understanding across the IATF 16949 community and support continual improvement.
IATF 16949 · IAOB audit data One card per clause. Each one gives you the finding in a sentence, then the three stages behind it — what the auditor saw, why it happened, and what closed it out. 10.2.3 Problems were closed without ever establishing the root cause or checking that the fix worked. 01What the auditor saw 02Why it happened 03What closed it out 8.3.5.2 Process FMEAs and special characteristics were missing from the design outputs, or never carried through into the controls. 01What the auditor saw 02Why it happened 03What closed it out 10.2.1 Corrective actions were raised and signed off without evaluating the cause or verifying the result. 01What the auditor saw 02Why it happened 03What closed it out 8.5.1.1 Control plans didn't match what happens on the floor, the FMEA, or the change that should have triggered a reissue. 01What the auditor saw 02Why it happened 03What closed it out 7.1.5.1.1 Measurement system studies weren't run across the equipment in scope, or were run outside the required methods. 01What the auditor saw 02Why it happened 03What closed it out Four of the five come back to the same two things: documentation that doesn't reflect practice, and people who weren't trained or held accountable for it. Only 8.3.5.2 is a genuinely technical failure. Source: IATF Oversight Office (IAOB) analysis of major nonconformities raised against IATF 16949. Each stage shows the three most frequently cited items. Sub-clause detail is summarised, not quoted from the standard.The five clauses auditors write up most
Problem Solving
Manufacturing Process Design Output
Nonconformity and Corrective Action
Control Plan
Measurement System Analysis
