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Exhaust Emission Measurement Errors During Final Vehicle Inspections

August 9, 2018

IWATA, August 9, 2018—Yamaha Motor Co., Ltd. (Tokyo: 7272) received a request from the Ministry of Land, Infrastructure, Transport and Tourism on July 9, 2018 to report on its exhaust emission inspection processes, and subsequently conducted an internal review of these, which form part of the final inspection process carried out on automobiles coming off its assembly lines.

The review revealed that there were seven cases where Yamaha Motor failed to exclude test results where a “trace error” was indicated—instances where designated speed and/or time limits applied to test environments were exceeded—and processed these as valid results. Beyond the failure to exclude those results, no manipulation of test data or other regulatory breaches were found to have occurred.

Yamaha Motor has since excluded the seven results in question and conducted a full re-inspection of the affected vehicles, which confirmed that all results met the relevant security standards.

The failure to observe proper inspection processes was caused by omissions in the inspection routines governing cases where trace errors are identified, leading to improper validation of vehicle inspection results.

To avoid a reoccurence of this situation, Yamaha Motor has introduced new processes which tighten up the validation of test results by adding specific post-inspection tests checking for the presence of trace errors. A full review of overall inspection standards is also underway.

Yamaha Motor sincerely apologizes to all customers, partners and other stakeholders who may have concerns or have been inconvenienced as a result of these occurences.

Reference materials:
 Report on the investigation into fraudulent inspection of fuel consumption and exhaust emissions PDF(114KB)
 Supplement to “3. If, as a result of the investigation, cases of fraud, etc. have been discovered” PDF(289KB)

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