The Japanese automotive industry is being rocked by an emissions and fuel efficiency scandal right now, and it involves the Yamaha Motor Company motorcycle division as well.

All told, five of the eight automotive companies in Japan have been found incorrectly testing and reporting the emissions and fuel mileage of their vehicles.

The scandal started in 2016 with Mitsubishi, which lead to findings last year where Nissan and Subaru were found manipulating the results of their emission results. These findings then caused the Japanese government to require other automotive companies in Japan to check their testing operations.

Upon this internal review, Mazda and Suzuki found and reported that their cars had been improperly tested, with Yamaha finding similar results with its motorcycle standards testing.

This means that Suzuki, Mazda and Yamaha cleared vehicles for emissions or fuel efficiency, even in cases where these vehicles were tested under invalid conditions and methodology, according to the Japanese Ministry of Land, Infrastructure, Transport, and Tourism.

For example, these errors would cause deviations in the speed of the vehicles during testing, or the amount of time these vehicles were tested, which should have invalidated the test results.

To help explain the situation for our readers, it should be said that automakers in Japan test their own vehicles for emissions and efficiency standards, on behalf of the government.

This saves time and resources in the automotive manufacturing process, but is done so only with the good-faith participation of the OEMs involved.

Rechecking their original testing, Yamaha and the other automakers found no significant problems with actual emissions and fuel economy performances of the vehicles in question, once they were properly tested.

For Yamaha, this meant retesting seven motorcycle models in total (2% of the units were found to be improperly tested once the results were compared), and for all the brands this means that no recalls will be performed.

While Yamaha and the five other Japanese automotive manufacturers haven’t broken any laws, these finding do show that these companies were lackadaisical in their testing criteria and their adherence to Japanese testing standards.

It also means that the companies broke the trust of the Japanese government, and thus also broke the trust of the Japanese people.

The result has been a stark blemish on the record of the Japanese automotive industry, which has enjoyed a reputation for high engineering standards and attention to detail. In response to this, Mazda, Suzuki, and Yamaha have publicly apologized for their actions this week.

“Yamaha Motor sincerely apologizes to all customers, partners and other stakeholders who may have concerns or have been inconvenienced as a result of these occurrences,” the motorcycle company said in a press release.

On the news, Yamaha’s stock price on the Nikkei stock exchange dropped 5.3%, with the other brands suffering similar hits to their stock prices.

Source: Nikkei Asian Review & Reuters via Paul Tan Blog