Washington (CNN) -- Toyota engineers found an electronic software problem that caused "sudden unintended acceleration" in a test vehicle during pre-production trials, according to a company engineering document obtained by and translated for CNN. The 2006 document, marked "confidential," recounted the results of an adaptive cruise-control software test in a model internally designated the 250L, a vehicle later sold as the Lexus 460 in Japan and Europe. The document says a "fail-safe overhaul" would be needed for another model in production, internally designated the 180L, which the company says was later sold as a Toyota Tundra. Toyota insists that the document shows no such thing, and it continues to deny that any sudden unintended acceleration in any of its vehicles was caused by electronic systems. But three translations of the report, including two commissioned by CNN after Toyota's objections, found that engineers raised concerns that the adaptive cruise control system would start the car moving forward on its own.
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Translated Toyota report describes a cruise-control system test
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Experts say the translated report describes a software problem
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The company denies electronics are responsible for sudden acceleration
According to the third translation, Toyota's engineers stated that a test was conducted on the 180L "to prevent the accelerator malfunction that caused the vehicle to accelerate on its own" in an earlier test of the @placeholder.