Are cosmic rays really causing Toyota's woes?

It may sound far-fetched, but federal regulators are studying whether sudden acceleration in Toyotas is linked to cosmic rays.

Radiation from space long has affected airplanes and spacecraft, and is known for triggering errors in computer systems, but 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.

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," Sung Chung, who runs a California testing firm, said.

Toyota, which has led the auto industry in using electronic controls, told the Free Press its engine controls are "robust against this type of interference."

Cosmic rays offered as acceleration cause

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 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."

Toyota staunchly defends its electronics, saying they were designed for "absolute reliability." Responding to the Free Press, Toyota said its systems "are not the same as typical consumer electronics. The durability, size, susceptibility and specifications of the automotive electronics make them robust against this type of interference."

Testing for the problem would involve putting vehicles in front of a particle accelerator and showering them with radiation, a step that experts said would help resolve the question.

"Nobody wants to come out and say we have issues and we need to test," said Sung Chung, president of the testing firm Eigenix. ...

via Are cosmic rays really causing Toyota's woes? | freep.com | Detroit Free Press.