How to read OEM part numbers by brand: VAG, BMW, Toyota, Mercedes and more

Why number formats matter

A part number isn’t random. Most carmakers build meaning into it: a group code, a sub-assembly, a revision index. Once you know the shape, a number that looks off looks off — and you catch the transcription error at the counter instead of at goods-in.

Volkswagen Group (VAG): three-three-three plus an index

VAG — Volkswagen, Audi, Škoda, SEAT — uses a 3-3-3 block plus a one- or two-letter index, like 1K0 615 301 AB. The first block ties to the vehicle/type, the middle to the main group, the last to the part, and the letters mark the revision. The shared scheme is why one ETKA catalog serves all four brands.

BMW: eleven grouped digits

BMW (and MINI, Rolls-Royce) uses an 11-digit grouped number, like 34 11 6 794 300. The first two digits are the main assembly group — 34 is brakes, 11 is engine — which makes BMW numbers quick to place once you learn a handful of group codes.

Toyota, Mercedes, Hyundai/Kia

Three more you’ll meet daily:

• Toyota/Lexus: a five-plus-five number, like 90919-02240 — first group is the family, second the item.
• Mercedes-Benz: an A-number, like A 000 905 12 00, tied to the FIN (the Mercedes VIN).
• Hyundai/Kia/Genesis (Mobis): a 5-5 number, like 86511-XXXXX, shared across the group.

Read the shape, then trust the catalog

Knowing the format helps you sanity-check a number and talk to suppliers. It doesn’t replace the catalog: numbers supersede, and only the EPC tells you the current one for the exact build. Use the shape to catch errors, use the catalog to be right.