Automotive Electronics Specification Example for City Buses: Sealed Unit
Automotive Electronics Specification Example for City Buses: Sealed Unit
This is a worked specification for automotive electronics in a sealed unit programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The sealed unit version exists because the duty cycle on city buses is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually reorders that did not match the approved sample.
Example specification
| Item | Automotive Electronics |
|---|---|
| Application | City Buses |
| Version | Sealed Unit |
| Base material | Carbon Steel |
| Controlled dimensions | 4 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | painted |
| MOQ | 500 pieces per specification |
| Sampling | 10 working days, 3 days per revision |
| Compliance | IATF 16949 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Carbon Steel, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.
Processes involved
- precision stamping
- ultrasonic cleaning
- injection moulding
- shot blasting
- sintering
- die casting
Where this example applies
Programmes that run sealed unit most often specify this build for city buses. Related applications include light trucks, city buses, courier fleets, rental motorcycles, municipal fleets.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 2.5 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
How is packing specified?
Individual packing, inner box quantity and carton marking are confirmed at quotation stage so the cartons arrive ready for your warehouse.
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
How long does sampling take?
Samples leave the factory in 10 working days, and each revision round adds about 3 days once you have seen the first piece.
What testing is included?
Standard lots ship with dimensional and hardness reports. IATF 16949 documentation is issued with the shipment when your market requires it.
Tell us the model, the fitment and the quantity and we will hold a production slot for you.
