Your roadside unit talks to a vehicle. The demo works. The radio behaves, the software behaves, and the team is ready to talk about production.
Then the questions change. Can another team build the same unit? Can they prove it performs? Can they keep its configuration identical from batch to batch?
That's the real manufacturing challenge behind vehicle-to-everything (V2X) hardware. V2X enables vehicles to exchange data with each other, roadside infrastructure, and networks. For transportation original equipment manufacturers (OEMs), a working demo is the start of the manufacturing conversation, not the end. Plan design, assembly, test, and security together, and you'll meet far fewer surprises on the way to production.
A V2X ecosystem has two kinds of hardware, and they lead very different lives.
Onboard units (OBUs) sit in vehicles. Roadside units (RSUs) sit on gantries, on poles, and in junction cabinets. Between them, they carry the messages that make V2X work. A typical unit packs a processor, radio circuitry, antennas, power management, and a global navigation satellite system (GNSS) receiver into one assembly. On a development board, that's a neat block diagram. In a finished product, there are many parts that all have to work together.
The environment pulls the two apart. An OBU copes with vibration, power supply disturbances, and a cabin that bakes in a parked car. An RSU copes with weather, solar load, and a service life measured in years, often beside a live road. Same job, very different specification. That's why transportation OEMs need to think about the installation environment as early as the block diagram.
The radio depends on where you're selling. Direct communication uses cellular V2X (C-V2X) or ITS-G5, depending on the market. In the US, DSRC operations in the 5.9 GHz band are due to end on 14 December 2026, with C-V2X taking over. In the UK, trials such as UK CITE have used ITS-G5 roadside units. If you're building for more than one market, settle the radio technology and regional requirements before you lock the manufacturing plan.
Prototypes hide things. A hand-tuned antenna here, a bit of foam there, a tweak only one engineer remembers. Repeatable production means finding those details and turning them into controlled specifications before you release the design.
Radio performance is sensitive. Board stack-up, material properties, connector assembly, antenna placement, and enclosure geometry can all shift it. So specify the critical tolerances and approved materials, then validate the assembled product against defined limits. ESCATEC’s PCB assembly services support customers from the prototype and industrialisation stages through to ongoing manufacture.
Watch the move from a machined prototype housing to an injection-moulded plastic. Material, wall thickness, and mounting geometry all affect the antenna, so they are controlled design inputs rather than packaging choices. Review antenna performance whenever the housing changes.
Heat depends on where the unit lives and how it's built. A cabin-mounted OBU still has to survive a parked car in summer, and climate control isn't a substitute for qualification. An outdoor RSU has to shed heat through a sealed enclosure while sitting in direct sun.
So write it down: thermal pad position, interface material, fastener torque, sealing method, and inspection criteria. If those details live only in the prototype engineer's head, your manufacturing package isn't finished.
Testing means four different things in V2X, and mixing them up is how programmes get caught out. Passing one doesn't mean you've passed the others.
Production testing asks whether each unit was built correctly. Depending on the design, it might cover power consumption, processor and memory operation, programming verification, interfaces, and selected RF measurements.
Decide which checks run on every unit and which use sampling, based on failure risk, coverage, and process capability. Then plan fixture access and cycle time, and keep a reference unit to maintain consistent measurements across stations. At ESCATEC, we offer flying probe, in-circuit, boundary scan, and functional test, and we can develop a functional test in-house or implement yours.
Environmental qualification asks whether the design will survive its life. Define temperature, vibration, shock, moisture, and any other exposures relevant to the real installation.
And remember that qualified components don't make a qualified product. An automotive-grade integrated circuit says nothing about whether your enclosure, connectors, thermal interfaces, or finished assembly will cope.
Conformance testing asks whether the radio meets the rules. In Europe, ETSI EN 302 571 is the harmonised standard for ITS radio equipment in the 5855 to 5925 MHz band. In the UK, the Radio Equipment Regulations 2017 apply, with UKCA or CE marking.
Interoperability testing asks whether your unit works with everyone else's. The OmniAir C-V2X certification programme covers interoperability and security for OBUs, RSUs, and modules. Neither replaces verification on the line. Work out which route applies to your deployment, and decide who owns the testing, the evidence, and the approval.
Security doesn't stop at the software team. Anywhere manufacturing touches firmware, device identity, or credentials, security must be built into the production instructions. Agree where the boundary sits between your design authority, your electronic manufacturing services (EMS) provider, and the deployment operator before the pilot build, not after.
Release approved firmware through a controlled process. Record the hardware revision and firmware version against each unit, restrict programming access, and verify the loaded configuration before release. If secure boot is enabled, verify that the unit actually boots as expected.
A device's identity might sit in a secure element or another protected implementation. Certificates can be provisioned during manufacturing, at installation, or at later enrolment, depending on your public key infrastructure (PKI) architecture.
Whichever route you choose, write down who's responsible for key generation, credential handling, failed provisioning, rework, and device retirement. And keep sensitive key material out of ordinary work instructions and open production records.
Supply planning also needs to reflect the market you serve. Our analysis of transportation infrastructure growth explores how opportunities and production demands differ across transport sub-sectors, including smart mobility and connected infrastructure.
A roadside unit can stay in service for years. The parts inside it won't stay in production that long. Radio devices, positioning modules, memory, security components, and enclosure materials all deserve a lifecycle review against your production and spares demand.
That's where ESCATEC’s supply chain team comes in. We monitor component lifecycle information, review bill of materials (BOM) exposure, and support alternative-part and second-source evaluation, with last-time-buy decisions where needed.
Be careful with substitutes. A replacement part can change RF behaviour, firmware compatibility, thermal performance, or certification scope. Use controlled engineering change notes to define effectivity, stock disposition, documentation updates, and any retesting. And treat an alternative as qualified only once the evidence has been reviewed, and your design authority has signed it off.
A good transfer package lets another team build, configure, and accept your product without relying on anything undocumented. Review it before new product introduction (NPI) begins, because gaps are far cheaper to find on paper than on the line. Here's what to have ready:
The best time to find a build problem is while you can still change the design. An early manufacturing review brings unresolved decisions into the open. Our DfX reviews look at electrical, mechanical, firmware, and supply chain risks alongside production requirements. Bring the enclosure, the antenna arrangement, a draft BOM, and your proposed test strategy.
As an EMS partner, we bring design-for-manufacture input, assembly processes, test implementation, and supply planning. Radio validation, credentials, and certification stay with your design authority, and we agree on who owns what from day one.
So here's the question to ask: which details still depend on the original engineer adjusting the product by hand? Those are the ones to resolve before you ask anyone to build it again and again. Talk to our team about your V2X programme.
Production testing checks that each manufactured unit meets release limits. Conformance testing checks that a representative design meets the applicable communications specifications, usually at an accredited test house.
Antenna integration matters during manufacturing because antenna performance depends on the finished assembly. Enclosure materials, mounting geometry, and nearby conductors all play a part, and production variation can change RF behaviour. Specify critical tolerances and agree on measurements that catch real defects. A successful prototype demo alone won't tell you.
Not necessarily. Provisioning can happen during manufacture, at installation, or at later enrolment, depending on the deployment's PKI architecture. What matters is an agreed process for device identity, credentials, and verification, with clear responsibility for secure handling, rework, and records at each stage.
Yes, within limits. An EMS provider can contribute design-for-manufacture input, assembly processes, test implementation, and supply planning. V2X-specific radio validation, credentials, and certification should be agreed explicitly for each programme.
You should involve an EMS provider early in the process, while the design can still change. ESCATEC's design support and NPI services connect product requirements to build and test planning, and an early review gives you time to resolve access, assembly, and component risks before production release.