How do states use OBD II for emission inspections?

Many states connect a computer directly to a vehicle's OBD II system. The inspector can then read "faults." In some states, this type of inspection has replaced the tailpipe emission test.
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Living With the C30
You'd be forgiven for thinking "hatchback = practical," but that's not quite
the case with the C30. Sure, it's more practical than a two-seat roadster, but
this isn't a family car — unle ...
Vanity mirror
Vanity mirror with lighting
The light comes on automatically when the cover is lifted. ...
Steep inclines and/or heavy loads
ACC is primarily intended for use on fairly level
roads. The system may have difficulty maintaining
the correct distance to a vehicle ahead
on steep inclines, if the vehicle is carrying a
heav ...
