Hugh Pickens writes "As electronic devices are made to perform more and more functions on smaller circuit chips, the systems become more sensitive and vulnerable to corruption from single event upsets. This is especially true of Toyota, which has led the auto industry in its widespread inclusion of electronic controls in the manufacture of their various car models. 'These circuit families store not just data, but their basic function electrically,' says Lloyd W. Massengill, director of engineering at the Vanderbilt Institute for Space and Defense Electronics at Vanderbilt University. 'In the unfortunate event of a particle flipping just the right bit, a circuit configured to carry out a benign action may be reprogrammed to carry out some unintended action.' Denise Chow writes in Live Science that some scientists are pointing to cosmic ray radiation as a plausible mechanism behind the sudden, unexplained acceleration reported to have occurred with the late model Toyotas.""As the design of automobile systems continues to evolve from mechanical to electronic controls, relying more and more on various circuitry and chips, these electronic components may be vulnerable to being confounded by high-energy radiation writes Chow. Federal regulators were prompted to look into the possible role that cosmic rays played in Toyota's product recall fiasco after an anonymous tipster suggested the design of Toyota's microprocessors, software and memory chips could make them more vulnerable (PDF) to interference from radiation compared with other automakers. 'What's not known is what direction Toyota and other automakers are taking in terms of finding and correcting these issues,' says senior researcher Ewart Blackmore."