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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Vehicle Overview
New brushed-aluminum roof rails and an eggcrate grille go on 2005 XC70s. A
trip computer and rear armrest are also now standard. The headlights and
taillamps have been restyled, new front and rear ...
It's the little things that count
Storage Compartments (Puny, Fair, Ample, Galore): Fair
Cargo/Trunk Space (Puny, Fair, Ample, Galore): Ample ...
Opening/closing the fuel filler door
The fuel filler door is located on the right rear
fender (indicated by an arrow beside the fuel
tank symbol on the information display )
With the ignition switched off, press and
release the ...
