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Toyota Recalls 1.9 Million Prius Hybrids Over Software Flaw

More than half of all Prius hybrids ever sold are affected by a software glitch that can cause overheating in its electronics

2 min read
Toyota Recalls 1.9 Million Prius Hybrids Over Software Flaw
Photo: Toyota

Faulty software in Toyota's popular Prius hybrids has forced the Japanese automaker to recall 1.9 million of such vehicles worldwide. The huge recall—representing more than half of all Prius cars ever sold—shows how Toyota has adopted an increasingly cautious stance as major automakers struggle with the rise of software-related car problems.

The flawed Prius software can cause overheating and damage in transistors within the electronic system controlling the hybrid's gasoline-electric hybrid motor, according to The Wall Street Journal. That scenario can trigger warning lights on the dashboard and force the vehicle into a failsafe mode known as "limp home mode" that slows vehicle performance to a crawl. In "rare circumstances," Toyota warned that the hybrid system might shut down and bring the vehicle to a halt while it's being driven.

Another Wall Street Journal article reported that Toyota has received 451 reports of this particular software problem since May 2011. Toyota's subsequent recall covers all of the newest, third-generation Toyota Prius hybrids that have been produced since 2009. Almost 1 million of the recalled vehicles are in Japan, 700 000 are in the United States, and 130 000 are in Europe.

Toyota also announced a separate recall to update the skid control software for a combined 295 000 vehicles of other Toyota models: 2012 RAV4 sport utility vehicles, 2012-2013 Tacoma pickup trucks, and 2012-2013 Lexus RX 350 SUVs.

The Prius recall signifies the latest case in possible software-related problems for major automakers. Many modern cars use dozens of electronic control units (ECUs) and tens of millions of lines of software code—a scenario that will likely become even more complex as Toyota and other automakers move toward semi-autonomous or even fully autonomous self-driving car systems. Such complexity leaves plenty of room for more software glitches and bugs that could lead to costly recalls and potentially lawsuits.

Toyota has more than enough experience by now in learning how to address such issues. The automaker is still dealing with a 2009 controversy over sudden unintended acceleration (SUA) that sparked an initial recall of 3.8 million vehicles, as readers of IEEE Spectrum'sRisk Factor blog will know. Toyota has consistently argued that such incidents stem from driver error rather than any faulty vehicle electronics, but its lawyers recently took steps toward allowing for a broad settlement agreement.

In any case, Japanese investors seemed to view Toyota's latest recall without alarm as Toyota's stock ended up 0.4 percent after the announcement.

"My impression is Toyota is recalling more often, even with very minor flaws" with its vehicles, said Yuuki Sakurai, the Tokyo-based president of Fukoku Capital Management Inc., in a Bloomberg Businessweek interview. "Toyota learned its lesson from the big recalls in 2009 and 2010."

Photo: Toyota

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An IBM Quantum Computer Will Soon Pass the 1,000-Qubit Mark

The Condor processor is just one quantum-computing advance slated for 2023

4 min read
This photo shows a woman working on a piece of apparatus that is suspended from the ceiling of the laboratory.

A researcher at IBM’s Thomas J. Watson Research Center examines some of the quantum hardware being constructed there.

Connie Zhou/IBM

IBM’s Condor, the world’s first universal quantum computer with more than 1,000 qubits, is set to debut in 2023. The year is also expected to see IBM launch Heron, the first of a new flock of modular quantum processors that the company says may help it produce quantum computers with more than 4,000 qubits by 2025.

This article is part of our special report Top Tech 2023.

While quantum computers can, in theory, quickly find answers to problems that classical computers would take eons to solve, today’s quantum hardware is still short on qubits, limiting its usefulness. Entanglement and other quantum states necessary for quantum computation are infamously fragile, being susceptible to heat and other disturbances, which makes scaling up the number of qubits a huge technical challenge.

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