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.
See also:
Symbols and messages in the display
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Custom Build Program
In addition to traditional optional features like a navigation system, power
moonroof and Sirius Satellite Radio, buyers who want to customize the C30 can do
so through Volvo's Custom Build progra ...
Automatic transmission
Shiftgate positions
Depress the button on the front of the gear selector knob to move the gear selector
between the R, N, D, and P positions.
The gear selector can be moved freely between the Ge ...
