Daihatsu Motor Company Ltd, a subsidiary of Toyota Motor Group, has announced that from today it will temporarily suspend shipments of all Daihatsu-developed vehicles currently in production, both in Japan and overseas.

The move follows an investigation that found a large number of “irregularities” in the company’s testing procedures.

The Japanese automaker also confirmed that Toyota has also suspended shipments of the affected models, after an Independent Third-Party Committee commissioned by Daihatsu released the results of its investigation. It found new irregularities in 174 items within 25 test categories. This is in addition to the door lining irregularity found in April and the side collision test irregularity discovered in May.

Daihatsu’s total vehicle line-up of 64 models and three engines is affected, including 22 models and one engine sold by parent Toyota. The company said it “apologises for the inconvenience and concern this has caused to all stakeholders, including customers”.

Daihatsu confirmed that since the first irregularities were discovered it has conducted one-by-one, in-house technical verifications and actual vehicle testing on the affected models to ensure that their safety and environmental performance meet legal standards.

The automaker said that in the final stage of the investigation, it was discovered that a different airbag control unit (ECU) than the one fitted to the mass-production models was used for the airbag tests on the Daihatsu Move, Cast and Grand Max models, the Subaru Stella, the Toyota Pixis Joy and Town Ace, and the Mazda Bongo. While subsequent technical verification confirmed that the airbag met standards of occupant protection performance, it was found that the "Safety Performance Standard for Occupant Evacuation (Unlocking)" in the side collision test of Daihatsu Cast and Toyota Pixis Joy “may not comply with the law”.

Daihatsu confirmed that in all other cases of irregularities the performance standards specified by the regulations were met, with the validity of the verification results and process also having been confirmed by TUV Rheinland Japan (TRJ) - a third-party certification organisation.

The company added that so far it was not aware of any accident relating to this matter, but confirmed it is investigating the cause of the irregularities and will take necessary measures as soon as possible.