Who Can Prepare IATF 16949 PPAP Documents for a Tier-2 Supplier? A Plain Answer for Auto-Component Suppliers

By Yamm Labs · Updated September 2026 · 9 min read

The purchase order from the Tier-1 arrives with a line most Tier-2 owners have read before and few have fully unpacked: submit PPAP Level 3 with the first lot, per our supplier quality manual. The owner asks the obvious question at the next morning meeting. Who is going to prepare these PPAP documents? The answer has two halves, and the halves are usually confused with each other: who is responsible for the PPAP, and who may do the writing.

Who owns the PPAP, and who is allowed to write it?

IATF 16949 requires every certified supplier to run a product and manufacturing approval process that meets its customer’s requirements, and for most Indian automotive customers that means the AIAG PPAP manual, currently the 4th Edition. Ownership sits with the supplier. The customer approves or rejects, a consultant may assist, a laboratory may test, but the supplier’s responsible official is the person whose signature on the PSW warrants that the parts meet the design record and that the process can make them at the quoted rate.

Writing is different from owning. Neither the AIAG manual nor IATF 16949 requires that the supporting documents be authored inside the plant. When an outside provider prepares the Process Flow Diagram, the PFMEA or the Control Plan, the provider is an externally provided process under clause 8.4 of ISO 9001, which IATF 16949 adopts. The supplier defines what it needs, evaluates the provider, verifies what comes back and remains accountable for every page. The PPAP Desk service page describes that arrangement from the provider’s side: the desk prepares, the plant’s quality team verifies, the responsible official signs.

The eighteen elements: who prepares which

The fastest way to settle the who question is to split the manual’s eighteen elements into documents that can be authored from the drawing and the route, and evidence that only exists after parts have been made and measured. The table groups them that way.

Two lines in that table decide most disputes. The evidence rows never leave the plant: a provider who offers to supply capability numbers is offering to invent them, and a checker who finds that out will reject the whole pack. And the PSW row never leaves the plant either, whoever drafted the form.

Which internal role should lead the work?

• The quality or APQP engineer. This person leads the compilation, owns the PFMEA review, links it to the Control Plan and checks that every characteristic on the ballooned print flows into the dimensional report. In a small Tier-2 this is often the only engineer, which is where the capacity problem starts.
• Production and tooling. They provide the real route, the machine and fixture details, the setup sheets and the run-at-rate evidence. A PFMEA written without them describes a process that does not exist.
• Metrology and the laboratory. They run the Gage R&R, measure the parts and issue the material and performance test reports, either in-house or through a qualified external laboratory.
• The responsible official. Usually the plant head or the head of quality. This is the PSW signatory, and the person who should read the package index before signing rather than after the customer has.

What about sub-tier suppliers?

A Tier-2 that buys castings, forgings, plating or heat treatment is a customer to its own suppliers, and many customer-specific requirements make the Tier-2 responsible for obtaining, reviewing and approving the PPAP submissions of those sub-tiers before its own package goes up the chain. The practical rule is to ask your direct customer’s supplier quality manual what it requires for sub-tier approval, then run the same discipline downward: define the level, review the evidence, keep the approval on file. When a plant is preparing its own PPAP and chasing three sub-tier PPAPs in the same fortnight, the documentation load is what breaks first, which is the point at which an external desk earns its fee.

A consultant can prepare the pages; only the supplier can warrant the part.

What should a Tier-2 look for in an external preparer?

Start with the eighteen-element split above and ask the provider to mark, element by element, what it authors and what it expects from the plant. A credible provider will refuse the evidence rows. Ask whether it builds to AIAG PPAP 4th Edition and to your customer’s specific requirements and forms, because a pack in the wrong format is a rejection even when every number is right. Ask how the PFMEA is linked to the Control Plan and whether that link can be shown characteristic by characteristic.

Ask who validates the capability calculations and where the raw data lives. Ask what the turnaround is for one part and for a family, how many revision cycles are included, who signs the NDA on day zero and what the data retention period is after submission. The APQP, PFMEA and Control Plan questions hub covers the linkage questions in detail, and the PPAP documentation FAQ answers the submission-level and customer-format questions that usually come next.

How PPAP Desk fits a Tier-2 plant

PPAP Desk is the outsourced documentation service run by Yamm Labs for Tier-1 and Tier-2 automotive component suppliers. The plant sends the released drawing, the confirmed route, the gauge list, customer-specific requirements and its real measured data. The desk builds one characteristic-to-operation map and writes the documentation core of a Level 3 package from it: the ballooned print and characteristic register, the Process Flow Diagram, the PFMEA and Control Plan, the process and setup sheets, the checking-aid list and gauge specifications, the incoming inspection standard, the MSA, dimensional and initial process study formats, and a PSW draft with a package index.

The plant verifies every document against the shop floor, fills the evidence formats with its own data, and its responsible official signs. A two-part pilot runs on a five-day cycle, there is no retainer, and the pilot is free. The desk’s public case study is Manu Auto India, for which it has delivered more than fifty Level 3 reports in a consistent, indexed format.

A step-by-step plan for preparing PPAP documents at a Tier-2 plant

Whoever does the writing, the order of work is the same. Each step depends on the one before, and most rejected packs skipped one of them.

1. Confirm the design record. Lock the drawing revision and every authorised engineering change before a single document is written.
2. Confirm the submission level and the forms. Read the direct customer’s supplier quality manual and customer-specific requirements for the level, the forms and any sub-tier approval it expects.
3. Confirm the route. Production and tooling agree the real sequence of operations, machines and fixtures. Nothing downstream is reliable until this is fixed.
4. Build one characteristic map. Balloon the print and number every characteristic once, so the same numbers run through every later document.
5. Write the Process Flow Diagram, PFMEA and Control Plan in that order. Review the PFMEA cross-functionally, then carry its controls into the Control Plan, operation by operation.
6. Issue the evidence formats. MSA, dimensional report and initial process study formats go to the plant, built from the same characteristic map.
7. Generate the evidence. The plant runs the Gage R&R, measures the parts, commissions the laboratory tests and runs the trial. Only the plant’s own data goes in.
8. Close the sub-tier loop. Obtain and review the PPAPs of castings, forgings, plating or heat-treatment suppliers where the customer requires it.
9. Index, read, sign, submit. Compile the package index, have the responsible official read it, sign the PSW, and submit to the direct customer.

Customer requirements and manual editions change, so confirm the current text with your quality and compliance team before the first pack goes out.

How to brief an external desk on PPAP documents

A desk can only write from what it is given. A short, complete brief on day zero saves more time than any turnaround promise. Send the released drawing, the confirmed route, the gauge list, the customer-specific requirements and forms, and the submission level, and say which measured data the plant already holds.

Then agree the split in writing, element by element, using the table above: what the desk authors, what the plant supplies, and who reviews each document before it moves on. Agree how many revision cycles are included, who at the plant verifies each draft against the shop floor, and when the NDA is signed. Name one engineer at the plant as the single point of contact, so questions about the route or a characteristic reach someone who can answer them the same day.

Finally, agree what comes back. A usable handover is the documentation core, the evidence formats ready for the plant’s data, a PSW draft and a package index. Anything that arrives with numbers already filled in, which the plant did not measure, goes straight back.

Common mistakes when a Tier-2 outsources the writing

Outsourcing the writing is allowed. These are the ways it goes wrong, and each one traces back to confusing who writes with who owns.

• Accepting supplied numbers. Capability indices, Gage R&R results or dimensional readings the plant did not generate are invented data, and a checker who finds them will reject the pack.
• Writing the PFMEA away from the shop floor. A PFMEA drafted without production and tooling describes a process that does not exist, and the Control Plan built on it inherits every gap.
• Using the wrong format. A pack in a generic template, when the customer asked for its own forms, is a rejection even when every number is right.
• Letting three authors number characteristics three ways. The PFMEA, the Control Plan and the dimensional report must describe the same operations in the same order with the same characteristic numbers.
• Signing the PSW before reading the index. The responsible official’s signature is a warrant. The index is the fastest way to see what is actually in the pack.
• Forgetting the sub-tiers. A clean Tier-2 pack can still stall if the casting or plating supplier’s approval is missing from the file.

People also ask

Does a Tier-2 supplier submit its PPAP to the OEM or to the Tier-1?

To its direct customer, which is normally the Tier-1. The Tier-1 reviews and approves the Tier-2 package and may fold it into its own submission to the OEM. Direct submission to the OEM happens only when the Tier-1 or the OEM specifically requires it.

Can an external consultant sign the Part Submission Warrant?

No. The PSW is signed by the supplier’s authorised representative and approved by the customer’s authorised representative. A consultant may draft the form and the package index, but the warrant is the supplier’s.

What qualifications should the person preparing the PPAP have?

Working knowledge of the AIAG PPAP manual and the customer’s submission level, IATF 16949’s requirements for externally provided processes, the core tools of APQP, PFMEA, Control Plan, MSA and SPC, and the customer-specific requirements that decide the forms. The same applies whether the person is on the payroll or at an external desk.

Is a Tier-2 responsible for its own suppliers’ PPAPs?

Often, yes. Many customer-specific requirements make the Tier-2 responsible for obtaining, reviewing and approving sub-tier submissions before its own package is sent. Check your direct customer’s supplier quality manual for the level it requires.

Which PPAP documents can be prepared before parts are made?

Everything that comes from the drawing and the route: the ballooned print and characteristic register, the Process Flow Diagram, the PFMEA, the Control Plan, the checking-aid list, the MSA, dimensional and initial process study formats, and a PSW draft with a package index. The evidence itself, from measurements, tests and trial runs, only exists once the plant has made and measured parts.

Can a Tier-2 supplier split PPAP work between its own team and an external desk?

Yes. One workable split is for the external desk to author the documentation core while the plant’s APQP engineer leads the PFMEA review and the plant generates all evidence. The split should be written down element by element, and the supplier still verifies every document and signs the PSW.

Who at the Tier-2 should sign off each document before submission?

The quality or APQP engineer checks that the documents link together and match the shop floor. Production confirms the route and the PFMEA. Metrology and the laboratory confirm the evidence. The responsible official, usually the plant head or head of quality, reads the package index and signs the PSW last.