Most supplier comparisons focus on price, lead time, and sample quality. Those three factors tell you almost nothing about what will happen in year three. This checklist covers the twelve questions that do — grouped into four areas, each with the reason the question matters.
1. Which authority issued the approval, and what is the number?
Approvals are granted by specific authorities, and the number can be verified independently. If a supplier cannot supply the number and issuing authority, verification is impossible.
2. Which models does the approval cover?
Approvals apply to specific models and test conditions — not to a supplier’s whole catalogue. Confirm your exact model is listed.
3. Who is the registered approval holder?
If the holder is a different company from the entity invoicing you, ask why, and get the relationship documented.
Group 2: Production Control and Traceability
4. Do you own the production facility?
If production is subcontracted, the authorisation agreement and the factory’s quality accreditation both matter. Resellers cannot answer conformity questions on a manufacturer’s behalf.
5. How is incoming material controlled?
Lens material, LED sources, and housing components determine performance. Ask how incoming goods are inspected against specification.
6. Can you trace a finished unit back to its components?
Batch traceability is what allows a quality issue to be contained quickly instead of becoming a fleet-wide problem.
Group 3: Change Management and Documentation
7. What happens when a component changes?
The critical question. A locked bill of materials plus a documented engineering change notification process is the minimum standard.
8. Will you notify me before a change is made?
Notification — not disclosure on request — is what protects your compliance position.
9. What test documentation can you provide?
Photometric data at defined angles, EMC test reports, and environmental test results including UV ageing and temperature cycling.
Group 4: Continuity and Service
10. How long has the facility operated continuously?
Established in 1987, Zhejiang Liyi has operated through the industry’s shift from incandescent and strobe technology to LED. Continuity is evidence of a system that has been maintained, not just launched.
11. What is your spare parts commitment?
Fleets buy replacement units for years. Ask how long parts will be available for the model you order now.
12. Can I visit or audit the facility?
A supplier with nothing to hide welcomes this. Reluctance at this stage is a stronger signal than anything on a quotation.
Score each supplier on how completely they answer, not on how confidently. A partial answer with documentation beats a confident answer with none — and suppliers who cannot satisfy Groups 2 and 3 are unlikely to protect your programme over time, regardless of price.
Q: Can a supplier answer all twelve questions and still fail?
A: Yes. Answers should be verified independently — particularly the approval number and any test claims. The checklist establishes what to ask, not what to believe.
Q: How many suppliers should I evaluate?
A: Two or three is usually enough. Beyond that, the cost of evaluation outweighs the small differences you are likely to find in the qualified segment.
Q: Does a lower price ever justify a gap in Groups 2 or 3?
A: No. A cheaper unit that changes specification without notice puts your compliance position at risk, and the cost of that risk sits with the importer — not the factory.
Before you place an order, work through this checklist with every supplier on your shortlist. LIYI provides its approval details, production records, and change control process on request.
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