Did Toyota Do Anything Wrong?

Here is a list of decisions that Toyota would want to revisit if they could.

  1. Electronics components have a non-zero failure rate. Given this fact, a safety-critical system ought to have more fail-safes not fewer. Toyota did not install brake overrides even though it has been around for more than 10 years (see Audi 5000, Sudden Acceleration of). The number of SUA complaints spiked in 2002 when Toyota introduced ETCS-I across many of its models. However, Toyota engineers did not pick up the trend and put in well-known fixes. When Mr. Toyoda, the President of Toyota, said in the congressional hearing yesterday that he is “absolutely confident” that there are no problems in the electronics of Toyota vehicles, with all due respect, his subordinates are over-simplifying the situation to him.
  2. Gas pedals getting stuck in floor mats is NOT new. This has happened with other vehicles earlier. Toyota did not pay attention to this issue when even early-year Lexus models had these problems.
  3. Automobiles made by the Detroit Three have black-box recorders which store lots of relevant information AND the recorders can be directly accessed by consumers. Even though Toyota vehicles have black-box recorders, Toyota claims that they store only limited amount of data for a small number of seconds, AND the stored data can only be read by Toyota. If the black-box recorders stored more information for more time and can be read by the consumer, Toyota could exonerate itself very quickly by showing that driver error was the primary culprit.

The above blunders from the past may haunt Toyota for quite some time. They are beginning to add smart pedals on all their future models. These pedals will allow the driver to override any acceleration by braking (if both the gas and brake pedals are pressed, the brakes are deemed to override the gas pedal). A recall of 6 million vehicles was initiated recently to deal with the floor mat problem and another recall of about 2.5 million vehicles was initiated to look at sticky gas pedals. (The stick gas pedal issue, however, almost seems to be a non-issue in terms of injuries and deaths attributed to sudden acceleration).

Recommendations

Toyota and NHTSA must take a very close look at shielding cables to minimize the impact of EMI (electro-magnetic interference), all connectors to eliminate loose wiring harnesses, ESD (electro-static discharge) possibilities, differences in grounding potentials across the vehicle, assumptions behind the hardware and software components, code reviews, overall architecture and integration strategies.

In addition, revisit the testing strategies used by suppliers of the electronics. Do they test each product being delivered? How do they test them? What is the failure rate of components? What fraction of devices are found faulty (using sophisticated and time-consuming test equipment) but pass inspection otherwise? What kinds of failures occur on devices that do not pass inspection? Can the same kind of failures happen over time on devices that pass inspection? Are any tests repeated after 1, 2, 4, and 8 years of usage?

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