Toyota plus 4 other Japanese automakers caught cheating on certification tests

Mazda, Yamaha, Honda, Suzuki all copped to lying on reports, while Toyota is still under investigation

Several Japanese automakers have been caught falsifying certification tests, and Toyota might be the worst offender.

The Japanese Ministry of Land, Infrastructure, Transport and Tourism (MLIT) reported yesterday that its ongoing investigation into 85 domestic manufacturers, including several automakers, had found that most were acting in accordance with the law, but not Mazda, Yamaha, Honda, or Suzuki.

All four investigated their own operations per MLIT orders, found type approval applications falsifications, and were "found guilty of fraud," the ministry said. Offending companies were ordered to suspend shipment of vehicles whose certification tests were falsified and correct their shortcomings as soon as possible.

Mazda was found to have rewritten its engine control software to affect output testing, while Yamaha and Honda both submitted false noise tests. Suzuki lied about braking system test results, and Mazda also falsified crash tests. 

And then there's Toyota

Of the five major Japanese automakers caught up in the fraud, only one – Toyota – is still under investigation. No stranger to being caught in a lie, the automaker has gone into full apology mode.

Toyota issued its own detailed statement to further explain what MLIT reported as "submission of false data in pedestrian protection tests for three currently produced vehicles" and "falsification of crash test vehicles for four previously produced vehicles." The lies actually served the interest of consumers, Toyota claimed. 

Toyota said it found six instances among those seven models "where testing methods differed from the standards defined by national authorities," but stressed that none of the vehicles involved are unsafe. 

Shinji Miyamoto, chief at Toyota's Customer First Promotion Group, said that in most of the cases "more severe test conditions" were employed, and their data supplied to the government was above and beyond what was strictly required under law. In one example, a heavier moving barrier was used to test for rear-collision fuel leakage than mandated by law, resulting in a greater impact.

Toyota also failed to differentiate between passenger and driver sides when reporting damage to a pedestrian's head and legs in a side-on impact, and in another case Toyota submitted data on luggage shifting risks using an old, out-of-regulation luggage test block. Finally, Toyota failed to achieve targeted engine power in a test, and instead of stopping it to fix matters as required, "the engine control system was adjusted … and the re-tested data was used for certification," Miyamoto said.

Toyota added: "we conducted internal verifications on all the cases and confirmed that they all meet the legally defined standards and can, therefore, be used safely by our customers," Toyota chairman Akio Toyoda said of affected vehicles.

"Nevertheless, these acts shake the very foundations of the certification system, and as an automobile manufacturer, we believe they are acts that must never be committed," the chairman added. "As the person responsible for the Toyota Group, I would like to extend my sincere apologies … I am truly sorry."

Toyota said the tests affected its 2014 Crown model vehicles and 2015 model year Isis, Sienta, Crown and Lexus RX vehicles, none of which are in production any longer. Current vehicles caught up in the mess include the Corolla Axio and Corolla Fielder as well as the Yaris Cross, production for which has been suspended in Japan. 

It's not clear how many vehicles were sold under false certificates, or if any were distributed outside Japan. Toyota vehicles in the US, where models overlap, aren't affected, we're told.

"The issues identified by [Toyota Motor Corporation] are based on a review of past certifications to Japanese requirements," a North American Toyota spokesperson told The Register. "Vehicles sold in North America are certified using different processes and to different standards applicable to North American markets."

Toyota was caught earlier this year having faked certification tests for its diesel engines by rewriting engine performance software to incorrectly calculate results, à la VW, and in 2022 the company's Hino heavy vehicle subsidiary admitted to falsifying similar results going back as far as 2003.

Apologetic Toyota chairman Toyoda stressed that the investigation was ongoing (so did MLIT, which said "only the misconduct that has been discovered so far is listed") but said he believed the company was now moving in the correct direction with regards to getting on the right side of automotive regulators.

"These efforts will need to be done steadily and will take time, but I will go to the [factory floor] myself and take responsibility for their progress," Toyoda added. ®

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