Toyota to halt all Japan assembly plant operations due to system failure

Car maker says the suspension of operations is 'likely not due to a cyberattack'

A Toyota production line in Japan. The car maker's 14 plants in Japan account for about a third of its global production. AFP

Toyota will suspend operations at all of its assembly plants in Japan from Tuesday afternoon due to a malfunction with its production system, possibly bringing domestic output to a standstill for the world's top car maker.

The company is looking into the cause of the problem, said a representative, adding it was “likely not due to a cyber attack”. The malfunction has meant the company has not been able to order components.

Toyota suspended operations at 12 plants from Tuesday morning, with two remaining online. All 14 will be suspended from the second shift on Tuesday but the amount of lost output remains unclear, the representative said.

The 14 plants in Japan account for about a third of Toyota's global production, according to Reuters calculations. Toyota is the world's largest car maker by sales.

Toyota's shares were down 0.3 per cent at 2,429 yen ($16.58) in early Tokyo trade.

The suspension comes at a time when Toyota's Japanese production has been on the rebound after a series of reduced output plans it had blamed on semiconductor shortages.

Production in Japan was up 29 per cent in the first half of the year, the first such increase in two years.

Daily production in Japan for Toyota brands, excluding Daihatsu and Hino, averaged about 13,500 vehicles in the first half, based on a Reuters calculation of working days and excluding holidays.

Toyota's operations stopped last year when one of its suppliers was hit by a cyber attack. That one-day disruption caused an output loss of about 13,000 cars.

The car maker is a pioneer of just-in-time inventory management, which keeps down costs but also means that a snarl in the logistics chain can put production at risk.

While the cause of the malfunction was not clear, corporate Japan has been on alert in recent days as some businesses and government offices reported a flood of harassing phone calls.

The government has said the calls were probably related to Japan's release of treated radioactive water from the Fukushima nuclear power plant into the Pacific.