The research team, led by Kirill Levchenko, a computer scientist at the University of California San Diego, will present these findings at the 38th IEEE Symposium on Security and Privacy in the San Francisco Bay Area, from May 22nd to May 24th.
"We were able to find the smoking gun," stated Levchenko. "We found the system and how it was used."
Furthermore, copies of the code running on VW onboard computers were obtained from the automaker's own maintenance website as well as from forums run by car enthusiasts. The mechanism was running on a wide range of diesel-powered models, from the Jetta, Golf and Passat, all the way to Audi's A and Q-series cars.
To recap, the way VW's cheat mechanism worked was by allowing the car's onboard computer to determine when the vehicle was undergoing an emissions test. It was later evident that when this emissions-curbing system wasn't running, the cars emitted up to 40 times more nitrogen oxides than allowed under EPA regulations.
What Levchenko's team found was that a specific piece of code, labeled "Acoustic Condition", was actually not there to control the sound of the engine, but to alter emissions tests results. According to Phys.org, the code allowed for 10 different profiles for potential tests, checking for things like driving distance, speed and even the position of the wheel.
"The Volkswagen defeat device is arguably the most complex in automotive history," added Levchenko. "Dynamometer testing is just not enough anymore."
A less sophisticated mechanism was found by researchers on the Fiat 500X, whose onboard computer simply ran the emissions-curbing software for the first 26 minutes and 40 seconds following the engine start – which is the duration of most emissions tests.
Researchers also note that Bosch builds Engine Control Units (ECU) for both Volkswagen as well as Fiat, and that all the automakers had to do was to enable the code by entering specific parameters. Carscoops