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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IR-reflecting windshield
Section of the windshield where the IR-coating is
not applied
An optional factory-installed infrared (IR) coating
can be applied to the windshield to help
protect the cabin from the sun's heat a ...
The Looks
The improvements over the previous generation are of course most noticeable
by simply looking at the S80. I wouldn't call it striking, but it is handsome —
bordering on the masculine, yet still ab ...
Using City Safety
NOTE
The City Safety™ function is activated automatically
each time the engine has been
switched off and restarted.
On and Off
In certain situations, it may be desirable to
switch City Safety ...
