Daihatsu faked safety tests for 35 years — 174 cases, 64 models, plants frozen 5 months

In April 2023, Daihatsu — Toyota's wholly-owned small-car subsidiary — was found to have rigged side-collision safety tests for 88,000 vehicles, most sold as Toyota Yaris models in Thailand, Mexico, and Gulf Cooperation Council countries. The door trim on test cars had been notched to reduce injury risk, but the modification was never applied to production vehicles. The revelation was the start of a much larger scandal.

In December 2023, after an independent investigation, Daihatsu halted shipments of 64 models — including products sold by Mazda and Subaru and two dozen Toyota-badged vehicles — after uncovering 174 cases of misconduct dating back to 1989. Investigators found that airbag control units used in testing differed from parts in sold vehicles. Speed test results and headrest impact test results had been falsified. The misconduct accelerated after 2014.

The company shut all four of its Japanese manufacturing plants at the end of December 2023. Production remained halted through February to April 2024, when the shipment ban was lifted and plants slowly restarted. Full production resumed on 7 May 2024 — five months after the scandal broke. Affected markets spanned Japan, Bolivia, Cambodia, Chile, Ecuador, Indonesia, Malaysia, Mexico, Peru, Thailand, Uruguay, and Vietnam.

President Soichiro Okudaira, who had led Daihatsu since 2017, resigned amid the fallout. Masahiro Inoue took over in 2024. The scandal damaged Toyota's quality reputation and raised questions about oversight at the subsidiary level of one of the world's largest automakers. The fraud had persisted for 35 years because Daihatsu's internal culture prioritised meeting testing deadlines over accurate reporting, and Toyota's monitoring of its subsidiary had been insufficient.