EFF:

EFF is fighting for vehicle owners’ rights to inspect the code that runs their vehicles and to repair and modify their vehicles, or have a mechanic of their choice do the work. At the moment, the anti-circumvention prohibition in the Digital Millennium Copyright Act arguably restricts vehicle inspection, repair, and modification. If EFF is successful then vehicle owners will be free to inspect and tinker, as long as they don’t run afoul of other regulations, such as those governing vehicle emissions, safety, or copyright law.
 
 You can support EFF’s exemption requests by adding your name to the petition we’ll submit in the rulemaking.
 
 Most of the automakers operating in the US filed opposition comments through trade associations, along with a couple of other vehicle manufacturers. They warn that owners with the freedom to inspect and modify code will be capable of violating a wide range of laws and harming themselves and others. They say you shouldn’t be allowed to repair your own car because you might not do it right. They say you shouldn’t be allowed to modify the code in your car because you might defraud a used car purchaser by changing the mileage. They say no one should be allowed to even look at the code without the manufacturer’s permission because letting the public learn how cars work could help malicious hackers, “third-party software developers” (the horror!), and competitors.