Radiation from space long has affected airplanes and spacecraft, and is known for triggering errors in computer systems, but it has received scant attention in the auto industry.
The questions show how deep regulators and automakers may have to dig to solve the mysteries of sudden acceleration. Toyota says it is fixing mechanical problems floor mats and sticky pedals that explain sudden acceleration in 13 models and 5.6 million vehicles.
But at least half of more than 1,500 recent complaints to regulators involve other models, raising questions whether Toyota has fixed its problem.RelatedToyota is skeptical of Prius incidentSteps can be taken to regain out-of-control ToyotasDeaths in Toyotas leave questionsCalif. county sues Toyota over recall issuesToyotas quest for higher profits backfiresIncreased Prius acceleration complaints may be product of psychologyToyota recalls may lead to criminal chargesLawsuits over lost value could cost Toyota billionsToyota to examine Prius report
An anonymous tipster whose complaint prompted regulators to look at the issue said the design of Toyota's microprocessors, memory chips and software could make them more vulnerable than those of other automakers.
"I think it could be a real issue with Toyota," said Sung Chung, who runs a California testing firm.
Toyota, which has led the auto industry in using electronic controls, told the Detroit Free Press that its engine controls are "robust against this type of interference."'Single event upsets'
Electronics makers have known for decades about "single event upsets," computer errors from radiation created when cosmic rays strike the atmosphere.
With more than 3,000 complaints to U.S. regulators of random sudden acceleration problems in Toyota models, several researchers say single event upsets (SEUs) deserve a close look.
The phenomenon can trigger software crashes that come and go without a trace. Unlike interference from radio waves, there's no way to physically block particles; such errors typically have to be prevented by a combination of software and hardware design.
And an anonymous tipster told NHTSA last month that "the automotive industry has yet to truly anticipate SEUs."
Such radiation "occurs virtually anywhere," said William Price, who spent 20 years at the Jet Propulsion Lab testing for radiation effects on electronics. "It doesn't happen in a certain locale, like you would expect in an electromagnetic problem from a radio tower or something else."(2 of 2)
Toyota owners say fixes didn’t workWhat’s My Real Estate Really Worth?