What Is R156?
UNECE R156, officially titled "Software update and software update management system", is a United Nations regulation that regulates software update processes and manufacturer's software update management system (SUMS) requirements under the 1958 Agreement. It is not a test method, but a regulation defining the requirements for type approval and the tests by which these requirements will be verified.
Purpose of R156
The aim is to obtain E mark (e-mark) type approval by certifying that the vehicle or component meets the safety and performance requirements defined in the regulation.
Which Products Is R156 Applied To?
- Vehicles with OTA update capability
- Electronic control units
- Software configuration management processes
In Which Sectors Is R156 Used?
Standards Related to R156
- UNECE R156software update management system test
R156 Conditions
- Regulation
- UNECE R156 — Software update and software update management system
- Agreement
- 1958 Agreement (E/ECE/TRANS/505)
- working group
- Autonomous and Connected
- Serial change
- The series of amendments to be applied are determined according to the application date.
- Source
- The official text is published on unece.org
Equipment for R156
- Test setups required by the regulation
- Calibrated measurement and data recording systems
- Instrumented dummy and crash infrastructure if necessary
- Approved technical service laboratory infrastructure
Sample Requirements for R156
- The sample must represent mass production
- Technical file and information document should be prepared
- Vehicle/component category and variants must be defined
- The number of samples is defined in the regulation
Duration of R156
It depends on the scope and number of experiments. Component approvals can take days, full vehicle coverage approvals can take weeks.
R156 Procedure
- 1SUMS process and document audit
- 2Software authentication (RXSWIN) verification
- 3Pre-/post-update conformity assessment
- 4Control of user information and secure update flow
R156 Acceptance Criteria
Acceptance criteria are defined in the UNECE R156 text. For approval, all relevant clauses must be met and a conformity of production (CoP) scheme must be established.
Evaluation of Results
The results are matched individually with the regulation substances. Serial changes and transitional provisions to be applied affect the outcome; Therefore, the application date and target market should be clarified in advance.
R156 Report
- Applied regulation and series change
- Vehicle or component description and category
- Applied experiments and measurement results
- Compatibility table with regulatory substances
- Type approval information document annexes
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- UNECE R156
- 1958 Agreement
- EU Vehicle Type Approval Framework Regulation
Otomotiv Testleri — What Does This Testing Field Cover?
The section below describes the field that the R156 test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Automotive testing shows that a component keeps working under conditions representing the loads it will meet over the life of the vehicle. A vehicle is not a single product but an ENVIRONMENT: vibration, temperature cycling, salt water, stone impact, electrical transients and electromagnetic noise are all present at the same time and for years.
What distinguishes this family is that VEHICLE MANUFACTURER SPECIFICATIONS sit on top of the standards. ISO and SAE publications establish the common ground; but Volkswagen, BMW, Ford, Stellantis, Toyota and Renault define different severity levels, additional tests and different acceptance criteria in their own specifications. For a component, the phrase "complies with automotive standards" is not sufficient on its own; which manufacturer's specification, and which revision of it, must be answered.
The family carries three separate processes together and they are often confused. Homologation covers the type approvals a vehicle needs to enter traffic and runs under state authority. Supplier approval means passing the vehicle manufacturer's own quality and testing requirements and is a commercial relationship. The third is design verification: the engineering team demonstrating that its own design meets its targets.
At component level the test plan is built around the LOCATION OF USE. A module in the engine bay and a module in the boot do not go through the same temperature and vibration profile; a component inside a door and one in the roof console do not see the same water and dust exposure. The ISO 16750 series is the common framework for this location-based approach.
The shift to electric vehicles has reshaped the field. High-voltage safety, insulation coordination, battery safety, charging interface conformity and the electromagnetic behaviour of high-voltage components have been added to the classical automotive test set. In a quiet vehicle, acoustic and vibration expectations have changed too; sounds once masked by the combustion engine are now audible.
The quality system side cannot be separated from testing in this field. A manufacturer under IATF 16949 presents test results in the PPAP file; measurement system analysis, process capability study and the control plan stand around the test report. A single good result is not enough — the process must be shown to be able to repeat it.
Method groups in this field
Environmental and climatic
Temperature cycling, thermal shock, damp heat, salt spray, dust and water ingress (IP), solar radiation. Severity levels vary with the mounting location.
Mechanical
Sine and random vibration, shock, mechanical loads, fastener torque and durability cycles.
Electrical
Supply voltage variations, transients (ISO 7637), reverse polarity, overvoltage, short circuit and sleep current measurements.
EMC
Component emissions (CISPR 25), radiated and conducted immunity (ISO 11452 series), electrostatic discharge (ISO 10605).
Materials and emissions
Odour, fogging and VOC emissions from interior materials; flammability; UV ageing; coating durability and stone impact.
Functional safety and cyber security
Functional safety evidence under ISO 26262 and cyber security engineering under ISO/SAE 21434; these are tied to regulation through UNECE R155 and R156.
Commonly confused in this field
- An automotive report without a specification reference is not accepted in the supply chain; which OEM specification and revision was applied must be stated.
- Type approval and supplier approval are different processes. A component with E-Mark approval is not thereby considered to have passed the OEM's own acceptance tests.
- A result obtained on a prototype does not carry over to series production; PPAP is done with series production parts.
- On the EMC side, measuring emissions alone is incomplete; immunity is a separate body of work and is more critical in a vehicle.
- On electric vehicle components, high-voltage safety is a distinct competence; classical 12 V test infrastructure is not sufficient.
Which decisions these results support
- Supplier component approval and the PPAP file
- UNECE type approval and E-Mark marking
- Design verification and durability evidence
- Root cause analysis of field complaints and warranty returns
- Assessing the impact of a design or supplier change
Related Tests
Frequently Asked Questions About R156
Is UNECE R156 a testing standard?
Not. UNECE R156 is a type approval regulation: it defines together the requirements, the tests to be applied and the acceptance criteria. The tests are described in the annexes to the regulation.
What series of changes will be implemented?
The series to be applied depends on the application date and the series accepted by the target market. Transitional provisions are included in the regulation text and are determined together at the proposal stage.