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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Overview
The all-new Volvo S60 makes its international debut at the Geneva Motor Show
on Tuesday 2 March 2010. It launches into one of the automotive world's most
competitive segments backed by an elegant ...
Location of the keyless drive antennas
The keyless drive system has a number of antennas located at various points in
the vehicle.
1 - On the inside center of the rear bumper
2 - Left rear door handle
3 - Center of the parcel shelf, ...
Behind the wheel
Driving the XC70's turbocharged 3.0-liter V-6 took some getting used to. I
appreciated the surprisingly zippy kick-in-the-pants feel, as opposed to the
sluggishly heavy acceleration I anticipated ...
