Toyota will suspend overnight production at all 14 of its domestic plants due to a system malfunction, a rare glitch for the world’s biggest carmaker as it rushes to reboot its famed production system.

The malfunction has made it impossible to order parts, a Toyota spokesperson said, affecting some 28 assembly lines churning out everything from the top-selling Corolla and Camry to Prius hybrids. While it is not yet clear when operations will resume, the company does not suspect it is the victim of a cyberattack, the spokesperson said.

Twelve of the 14 plants were idled during the dayshift, with only Toyota’s Miyata plant in Fukuoka prefecture and the Kyoto operations of subsidiary Daihatsu unaffected. The problem currently appears limited to domestic plants, the spokesperson said.

Hino Motors, another Toyota subsidiary, said Tuesday it was also experiencing system issues and would halt four assembly lines across two Japanese plants.

Toyota shares fell as much as 0.8 per cent in early Tokyo trading after the production suspension was announced, before erasing most of the losses to close 0.2 per cent lower.

In February 2022, Toyota had to shut all 14 of its domestic plants after one of its suppliers was subjected to a ransomware attack. It took several days for operations to recover, and the incident impacted about 5 per cent of Toyota’s output for the month.

In July, a suspected Russian ransomware attack crippled Japan’s biggest port in Nagoya. Toyota, which relies heavily on the port, said shipments were temporarily halted but there was no impact on production.

Toyota produced and sold a record number of vehicles in June as operations continued to recover from a shortage of semiconductors and other parts. - Bloomberg