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:
Label information
1 Model plate: includes e.g., Vehicle Identification
Number (VIN), codes for color and
upholstery, etc. The model plate is located
on the rear side of the B-pillar (the pillar
between the front ...
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 ...
Checking and adding oil
Location of the filler cap and dipstick
Volvo recommends Castrol oil products
NOTE
Before checking the oil:
• The car should be parked on a level surface.
• If the engine is warm, wait for at ...
