It will just alert the driver not actually limit. [1]
Many systems already exists like that. Even simple ones which you can set by hand to a specific speed and it will beep when you go over.
[1]
""The Commission wanted to make it compulsory that the car would automatically slow down to observe speed limits but we have secured a compromise where the system merely has to alert the driver that he or she is speeding," said Daniel Dalton, the Tory MEP for the West Midlands."
Many systems already exists like that. Even simple ones which you can set by hand to a specific speed and it will beep when you go over.
[1] ""The Commission wanted to make it compulsory that the car would automatically slow down to observe speed limits but we have secured a compromise where the system merely has to alert the driver that he or she is speeding," said Daniel Dalton, the Tory MEP for the West Midlands."