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Inappropriate Handling of Motorcycle Testing and Certification Applications

June 3, 2024

Yamaha Motor Co., Ltd. has conducted an internal investigation following a directive from the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) to investigate whether or not there was any misconduct by the Company when submitting applications for model designations. As a result, we found two incidents of inappropriate handling during certification tests and reported the details of these cases and our actions going forward to MLIT on May 31, 2024.

We take incidents of wrongdoing very seriously and offer our deepest apologies to our customers, suppliers, business partners, and all other stakeholders for damaging their trust in Yamaha Motor.

Upon receiving the reports of these incidents, we have already retested and confirmed that there is no issue that will affect continued use of the vehicles in question, i.e., models we have currently suspended shipment of as well as those that have already been shipped.

1. Survey methodology and results
From February to May 2024, we conducted a questionnaire-based survey of those responsible for conducting certification tests or preparing application documents over the past 10 years, asking them if they have ever been involved in, seen, or heard of any misconduct. Furthermore, to check whether the application documents were correctly prepared based on internal reports of certification test results, we conducted an investigation cross-referencing the two documents. We also conducted interviews with the parties involved with questionable cases. To ensure independence and impartiality with these investigations, they were conducted by an external investigation organization with our Integrated Auditing Division taking the lead.

As a result, it was confirmed that improper noise testing was done, as these tests were conducted under conditions different from those specified by regulations. Further, with the sound pressure testing of vehicle horns, improper conduct was found in which applications were filed using VIN numbers other than the vehicle that was originally tested.

For the products concerned, we will take the necessary corrective steps following consultations and confirmations with the relevant authorities regarding the appropriate procedures, e.g., retesting and resubmission of test reports.

2. Incident details and models involved
Noise tests: Improper test conditioning (pretest adjustments)
For noise testing, a muffler with sound-absorbing glass wool is conditioned to simulate typical road use, but during the conditioning process, the certification testing personnel performed the conditioning at a different engine output than specified by regulations due to the testing equipment melting due to heat. The testers mistakenly judged that changing the engine output to avoid damaging the test equipment would not be a problem as long as it did not affect the durability and degradation of the sound-absorbing glass wool and satisfied the testing conditions for exhaust pressure, continuous operation, number of test cycles, and so on.

The model currently offered for sale that was tested under inappropriate conditions was retested under the correct conditions and found to still be in compliance with standards.

Shipments of the product concerned have been suspended at this time. We will take the necessary corrective steps following the resubmission of retest reports and other consultations with the relevant authorities. No issue has been found that will affect continued use of the vehicle, i.e., units we have currently suspended shipment of as well as those that have already been shipped.

Sound pressure testing for horns: When submitting applications for model codes, VIN numbers for vehicles other than those being tested were listed in the application documents
When applying for model codes, if using test results from vehicles that use the same or similar horn and installation conditions, the VIN number of the tested vehicle should be entered in the application along with a declaration that the performance of the tested vehicle is the same as the vehicle the application is for (management number and comparison table for the vehicle being applied for) when submitting the documents to the authorities.

However, due to an incorrect understanding of the rules, the personnel handling the applications did not include a comparison table and did not submit the VIN number of the previously tested vehicle and instead listed the VIN numbers of the vehicles being applied for.

We will take the necessary corrective steps for the products concerned following consultations with the relevant authorities, but it is Yamaha Motor's understanding that there is no problem with the actual use of the vehicles in question.

3. Causes
Noise testing: Improper test conditioning (pretest adjustments)
・We had an incorrect understanding of the law, assuming there would be no problem if some of the test conditions were changed as long as there was no physical influence on the scattering of the sound-absorbing glass wool.
・There was insufficient awareness of the importance in complying with legal regulations during certification testing, not only in terms of the impacts on test results but also the legitimacy of the testing process itself.
・Due to insufficient methods for ensuring legal compliance during the testing process and unclear delineations of responsibility in each stage of the process, proper checks were not performed and erroneous decisions made by the testing departments were not found.

Sound pressure testing for horns: When submitting applications for model codes, VIN numbers for vehicles other than those being tested were listed in the application documents
Laws, regulations, and rules related to certification applications were not properly circulated internally. As a result, personnel lacked a full understanding of the rules for the application process and applications were incorrectly submitted.

4. Measures to prevent recurrence
To prevent such incidents from ever happening again, we will take the following countermeasures:
・Clearly distinguish between certification work and development work in our testing rules.
・To ensure and maintain legal compliance in the certification process, provide regular training on the importance of the testing process, points to keep in mind, etc.
・Clearly designate certification departments as the responsible bodies to ensure legal compliance with the testing process.
・After creating an arrangement for keeping meticulous records of management items required in certification and development work, check the consistency of internal records and application documents as well as their legal compliance.
・Create a system to check application documents and internal reports within the department and ensure that the preparer and approver check each other effectively to keep the process from becoming a simple cross-checking formality.
・Clarifying the Company's interpretation of laws and regulations regarding the conditioning of vehicles for certification testing, turn them into company regulations, and disseminate them.
・Establish a system that ensures the procedures required by law and regulations for certification applications are incorporated in their entirety into the Company's own regulations.

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