What Is the VDA 6.3 Process Audit and How Does It Improve Supplier Quality?

The VDA 6.3 Process Audit is a standardized method developed by the German Association of the Automotive Industry (VDA) for evaluating process quality in manufacturing. It is widely used across the automotive supply chain to assess whether a production process is capable of consistently delivering products that meet customer requirements. This article explains what VDA 6.3 is, how it works, and how you can apply it—with a clear, illustrative example.

What It Is

VDA 6.3 is a process audit standard that examines the entire value-added chain, from product development through series production to customer service. Unlike product audits, which check the final output, a process audit evaluates the capability and robustness of the processes that create the product. The standard is structured around two main audit types:

• P1 – Potenzialanalyse (Potential Analysis): A quick, pre-award assessment used to evaluate a supplier's potential before a contract is awarded. It focuses on identifying risks early.
• P2–P7 – Process Audit: A full audit of the production process, covering seven elements: P2 (Potential analysis for new products), P3 (Planning of the process), P4 (Realization of the process), P5 (Supplier management), P6 (Production process analysis), and P7 (Customer care, after-sales service).

The audit uses a question-based approach. Each question is scored on a scale from 0 to 10, where 10 means full compliance and 0 means non-compliance. The results are aggregated into a "compliance rate" (Erfüllungsgrad), which determines the overall audit verdict.

How It Works / Formula or Steps

The VDA 6.3 audit follows a structured, step-by-step methodology:

1. Define the audit scope. Decide whether you are performing a P1 potential analysis or a full P2–P7 process audit. Identify the specific process or product to be audited.
2. Prepare the audit questionnaire. Use the official VDA 6.3 questionnaire, which contains hundreds of standardized questions across the P2–P7 elements. Each question is weighted according to its importance.
3. Conduct the on-site audit. Gather objective evidence through interviews, observation of production, and review of documentation (e.g., control plans, FMEAs, work instructions).
4. Score each question. Assign a score of 0, 4, 6, 8, or 10 per question, following the VDA 6.3 scoring rules:

- 10: Full compliance, no deviation.
- 8: Mostly compliant, minor deviation.
- 6: Partially compliant, significant deviation.
- 4: Insufficient compliance, major deviation.
- 0: Non-compliant.

1. Calculate the compliance rate. The overall result is expressed as a percentage (Erfüllungsgrad). The formula is:

Compliance rate (%) = (Sum of all awarded points / Sum of all maximum possible points) × 100

For a P1 potential analysis, the result is expressed differently—each question is classified as "red" (critical risk), "yellow" (moderate risk), or "green" (low risk), and the overall assessment is based on the number of red/yellow/green ratings.

1. Interpret the result. For P2–P7 audits, the compliance rate determines the audit conclusion:

- ≥ 90%: The process is capable; no significant action required.
- 80–89%: Minor deviations; improvement measures should be defined.
- < 80%: Major deviations; the process is not considered capable, and corrective action is mandatory.

A Worked Illustrative Example

Example data (illustrative only): Suppose you audit a supplier's production line for a plastic injection-molded part. The audit covers P6 (Production process analysis) with 20 scored questions. Each question has a maximum score of 10, so the maximum possible total is 200 points.

After the on-site audit, you award the following scores across the 20 questions:

• 12 questions scored 10 (full compliance) → 120 points
• 5 questions scored 8 (minor deviation) → 40 points
• 2 questions scored 6 (significant deviation) → 12 points
• 1 question scored 4 (major deviation) → 4 points

Sum of awarded points = 120 + 40 + 12 + 4 = 176 points

Compliance rate = (176 / 200) × 100 = 88%

Interpretation: With an 88% compliance rate, the process falls into the 80–89% range. The process is considered conditionally capable. The auditor must issue a report listing the specific deviations (e.g., the two questions scored 6 and the one scored 4) and require the supplier to submit a corrective action plan within an agreed timeframe.

Common Pitfalls

• Scoring too leniently. Auditors often hesitate to give low scores. Remember that VDA 6.3 requires objective evidence—if you cannot verify a claim, score it lower.
• Ignoring the P1 potential analysis. Many companies skip P1 and go straight to a full audit. P1 is a fast, cost-effective way to screen suppliers before committing resources.
• Focusing only on P6. While P6 (production) is the core, neglecting P2–P5 and P7 can miss upstream risks (e.g., poor supplier management) or downstream issues (e.g., after-sales).
• Not linking findings to corrective action. A compliance rate without a concrete improvement plan is of limited value. Always tie each low-scoring question to a specific corrective measure.

Closing

VDA 6.3 is a powerful, structured method to evaluate and improve process quality across the supply chain. By using its standardized questions and compliance-rate scoring, you can objectively identify weaknesses, drive supplier development, and reduce the risk of quality failures. To start applying VDA 6.3 in your own audits, try the free, interactive tool available at https://www.6sq.com/tools/vda63/, which guides you through the scoring and compliance-rate calculation automatically.