Free Buyer Resource

Wire Harness Factory Requirements Checklist

The 60-point checklist buyers use to brief a wire harness factory and get accurate quotes — the exact specifications and documents to confirm with your supplier before you release an RFQ. Free printable PDF.

Download the PDF Checklist

Most quoting delays and field failures trace back to one thing — an incomplete brief. Use this wire harness factory requirements checklist to lock down every specification before you send a supplier your RFQ. The more of these customer requirements you define up front, the faster and more accurate your quote, and the fewer surprises in production.

Work through all nine categories below, or grab the printable PDF to share with your engineering and procurement team.

1.Drawings & Documentation

  • 2D assembly drawing with overall and branch dimensions plus tolerances
  • Wire list / from-to schedule: every conductor's gauge, color, length, and both endpoints
  • Connector and pinout diagram for each connector position
  • BOM with exact manufacturer part numbers (avoid "or equivalent" unless pre-approved)
  • Revision number and date on every drawing and document
  • Approved-alternates list for long-lead or allocated components

2.Wire & Cable

  • Conductor gauge (AWG or mm²) for each circuit
  • Insulation type and temperature rating (PVC, XLPE, PTFE/ETFE, silicone)
  • Voltage rating per circuit
  • Shielding requirement: braid or foil, and required coverage %
  • Jacket material and color
  • Conductor stranding (fine-strand for flex / continuous-flex applications)

3.Connectors & Terminals

  • Connector manufacturer and exact part numbers: housing, terminals, and seals
  • Terminal plating (tin, gold, or silver) per application
  • Crimp specification and approved applicator / tooling
  • Gender, keying, and polarization for each connector
  • Cavity plugs / seals for unused positions on sealed connectors

4.Mechanical & Assembly

  • Overall length and each branch length, with tolerances
  • Breakout points and their dimensions
  • Protection: convoluted loom, conduit, braided sleeving, or tape — and coverage
  • Strain relief / overmold specification, including pull-force and minimum bend radius
  • Labeling and marking: wire markers, heat-shrink labels, and exact printed content
  • Mounting hardware: clips, cable ties, tie-mounts, P-clamps, and positions
  • Maximum bundle diameter or routing constraints

5.Electrical & Performance

  • Continuity / point-to-point map for 100% verification
  • Hipot (dielectric withstand) voltage and dwell time, if required
  • Insulation resistance threshold
  • Impedance and twist requirements for data or signal pairs
  • Maximum current per circuit

6.Testing & Quality

  • Is 100% continuity testing required?
  • Is hipot testing required, and to what spec?
  • Crimp pull-force testing and sampling plan
  • Target IPC/WHMA-A-620 class (Class 1, 2, or 3)
  • First Article Inspection (FAI / AS9102) required?
  • PPAP level required (automotive)?
  • Test reports and Certificate of Conformance with each shipment?

7.Compliance & Certifications

  • RoHS and REACH compliance
  • UL recognition and required style numbers
  • Industry QMS: IATF 16949 (automotive), ISO 13485 (medical), AS9100 (aerospace)
  • Region-specific marks (CE, etc.)
  • Material certificates and required level of lot traceability

8.Commercial & Logistics

  • Quantities: prototype count and estimated annual usage (EAU)
  • Minimum order quantity (MOQ) and price-break tiers
  • Lead time for prototype and for production
  • Tooling / NRE cost and ownership terms
  • Packaging: anti-tangle, ESD, individual bagging, or kitting requirements
  • Incoterms and shipping method
  • Payment terms

9.Communication & Sign-off

  • A single engineering point of contact (engineer-to-engineer)
  • Expected response-time / turnaround
  • Sample approval gate required before production release
  • Change control / ECN process
  • NDA signed before sharing drawings

Get the Printable PDF Checklist

Send it to your team and tick off every requirement before your next RFQ.

Prefer not to share details? Download the PDF directly.

Frequently Asked Questions

What should I send a wire harness factory in an RFQ?

At minimum an assembly drawing, a wire list, a connector/pinout list, a BOM with manufacturer part numbers, quantities (prototype plus annual usage), the operating environment, and your test and certification requirements. This checklist covers all of it.

What is the difference between an RFQ and this checklist?

The RFQ is your request for a quote; the checklist is the set of specifications that make that RFQ complete. A complete checklist means an accurate quote with no back-and-forth.

How many prototypes should I request?

Three to five is typical — enough for fit checks, electrical testing, and a retained golden sample.

Do I need to specify an IPC/WHMA-A-620 class?

Yes. Class 1, 2, or 3 sets the acceptance criteria for the whole build. If you do not specify, you may get a lower class than your application needs.

Ready to Quote?

Send WellPCB your drawings and this completed checklist — our engineering team responds within 24 hours with a realistic timeline and a transparent quote.

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