How do you find a part number from a photo?
A photo does not identify a part by its shape: it identifies it by what is written on it. Look for the marking first — aftermarket part number, barcode, brand logo, casting number — because it is the only thing that leads to a part number with no ambiguity. Without a legible marking, a photo cannot conclude on its own: it has to be cross-checked against the vehicle and the exact position of the part.
Director of publication : Florian Précigout
What a photo can prove, and what it cannot
A photo is excellent at carrying a fact: what is stamped on the part, the state of wear, the position on the vehicle, the number of connectors, whether a sensor is fitted. It is bad at settling a resemblance — two parts can look identical and still be incompatible, differing by a few millimetres or by their electronics.
The useful rule: a photo that shows text is worth ten photos that show a shape.
The four markings to look for, in order
1. The aftermarket part number. Etched, printed or on a label. It is the shortest path: it leads straight to the part and to its cross-references.
2. The OE part number. Often moulded into the material. It takes you back to the original fitment, and from there to the aftermarket alternatives.
3. The barcode or QR code. As long as it stays legible, it carries the part number with no risk of misreading.
4. The casting number or the logo. The least reliable — it often identifies a family, not a part. Use it as a last resort, never on its own.
Taking a usable photo
In practice, four reflexes change everything: clean the area around the marking, frame tight on the text, avoid direct flash which burns out etched characters, and take a second wide shot to show where the part sits on the vehicle.
That second photo matters more than people think. A marking with no context leaves open the question that costs the most at the counter: front or rear, left or right.
Photo and plate: two halves of the same answer
The two complete each other instead of replacing each other. The plate frames the vehicle and the part numbers that apply to it; the photo settles which one. When both agree, the doubt is gone — and that is exactly the move an experienced counter makes.
It is also what PartnAir does: the garage sends a photo of the plate, a photo of the part, a voice note or an etched part number, in a plain messaging thread. The agent turns it into a structured request, checks the part numbers against your catalogue sources — which stay yours, under attested licence — and asks for the missing criterion instead of guessing. Your team validates before the quote goes out.
FAQ
Can a car part be identified with no legible marking at all?
Rarely with certainty from the photo alone. You then have to work back from the vehicle and the exact position of the part to narrow the candidates, then settle it on a physical criterion — a dimension, a number of connectors, whether a sensor is fitted.
Is a part that looks identical necessarily compatible?
No, and that is the most expensive trap. Parts can share the same silhouette and differ by a dimension, a connector or their electronics. Resemblance is not an identification criterion.
Should you send one photo or several?
Two, ideally: one tight on the marking, one wide on the position on the vehicle. The first gives the part number, the second avoids an error of side or axle.