eCoC for stage 2 bodybuilders: what goes in the file and what doesn't

If you put bodies on someone else's chassis, you're a stage 2 manufacturer and the eCoC is yours to file. The good news is that the file is smaller than you'd think.

You only declare your stage

The VCA's own FAQ says it directly: multistage builders only need to complete the sections of the file that are mandatory or apply to their stage. It is not required to consolidate the previous stage's data for non-mandatory or unchanged sections. So no, you don't need Renault's engine data, emissions figures or approval number in your file. Your stage number, your approval, your dimensions and masses.

What's actually mandatory

The schema has hundreds of possible fields. The required ones are a short list: the VIN, your type approval scheme and number and the date it was granted, type, variant and version, vehicle category, how the plate is attached, who signed the certificate and where and when, the make, and your company's name and address as the manufacturer at your stage. That's it. Everything else, dimensions, masses, axles, bodywork code, colour, is optional and worth including because it's on your paper certificate anyway.

Where the previous stage's eCoC comes in

The VCA encourage chassis manufacturers to share their eCoC with the next stage, and once the VCA's public lookup (Phase 2) is live you'll be able to fetch it by VIN. But you don't need it to make your own file valid. If your paper certificate today says "as stage 1 base vehicle" for a field, that's a field you don't fill in.

The four values worth confirming

The paper certificate states some things in words that the file needs as codes: the approval scheme (GB unlimited series, medium series, and so on), how the statutory plate is attached, which side of the road the vehicle is built for, and the speedometer units. CoC AutoDocs sets sensible defaults and lets you change them once in the company settings. Confirm them with whoever holds your type-approval file before you go live, because they go into every file you make.

Check the exemption first

If your approval is national small series (NSSTA), you're permanently exempt from eCoC and can keep issuing paper. At more than a few hundred vehicles a year you're unlikely to be, but it's a five-minute check that could save the whole project.