PPAP within APQP

Production Part Approval Process (PPAP) is the method commonly used in automotive supply chains to demonstrate that production parts and the manufacturing process can consistently meet customer requirements. It is usually a Phase 4 APQP activity, but its evidence is created throughout the program.

What PPAP is—and is not

It is evidence of readiness

The submission assembles required evidence such as design records, approved engineering changes, process documents, measurement results, capability studies, material or performance results, and the Part Submission Warrant (PSW), as applicable.

It follows customer direction

The customer determines when a submission is required, the submission level, part requirements, format, and approval route. Do not assume a standard evidence list is sufficient for every customer.

It does not cure a weak process

Submitting forms cannot replace a stable, production-representative process. Resolve gaps before submission and control changes after approval according to customer and internal requirements.

PPAP readiness checks

Practical point: Treat the PSW as a formal certification of the submission, not a cover sheet. The authorized signer should understand the status of every required item and any deviation before signing.

After approval, APQP continues. Production data, audit results, complaints, and changes must feed into feedback and corrective action.